1

Guideline

Ambient Air Quality Monitoring Network

Recommendations and Rules

Content

Chap. 1 - Introduction

Guidelines for the Operation of the Air Quality Monitoring System

Concept of the Air Quality Monitoring Network

Chap. 2 - Measurement Strategy

Measurement Principles and Measurement Methods

Planning of ambient air quality measurements - General rules

Planning of ambient air quality measurements – Rules for planning

investigations of traffic related air pollutants in key pollution areas

Measurement Strategies for the Determination of Air Quality Characteristics in

the Vicinity of Stationary Emission Sources

Handling of Measurement Uncertainty

Siting of Air Quality Monitoring Stations

Chap. 3 - Operation of the Monitoring Network

Measurement Procedures for the Determination of Particulate Matter

Concentration and Gaseous Components

Monitoring network service

Performing of Maintenance/Maintenance Plans

Calibration of NO/NOx Analysers/Calibration Form

Calibration of SO2 Analysers/Calibration Form

Calibration of Ozone Analysers/Calibration Form

Calibration of CO Analysers/Calibration Form

Calibration of BTX Analysers/Calibration Form

Performing Repairs on Analysers/Repairs-Log

Change of Container Sites

Change of Measurement Location of Monitoring Vehicle (in German language)

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Chap. 4 - Calibration Laboratory

Calibration Laboratory

Receiving inspection, basic calibration, linearity test and type approval test for

suitability evaluation of measurement devices

Certification of test gases

Certification of test gas cylinders

Gravimetric Determination of PM10 Concentration by means of the High-

Volume-Sampler DIGITEL DHA-80

Gravimetric Determination of PM2.5 Concentration by means of the High-

Volume-Sampler DIGITEL DHA-80 (in German language)

Filter Handling (Cellulose Nitrate, Quartz Fibre) during the Determination of

PM10 Concentration by means of DIGITEL DHA 80

Filter Preparation and Storage (Cellulose Nitrate, Quartz Fibre) for the

Determination of PM10 Concentration by means of DIGITEL DHA 80

Balance Manual for the Verification of the Electronic Analytical Balance MC

210 P

Pipette Manual for the Verification of a Piston-Driven Air Displacement Pipette

by means of an Analytical Balance

Calibration of the Reference Standard, Organisation and Deadlines

Determination of Uncertainty of Measurement for the Pollutant Nitrogen

Dioxide (NO2) while employing a NO/NOx Chemiluminescence-Monitor

Chap. 5 - Network Data Centre

Recommendations on data validation in air quality monitoring networks

Recommendations on the calculation of aggregated data and statistical

parameters

Automatic validation of air quality data

Information of the public on air quality

Control and release of air quality data / Forms daily/monthly/yearly validation

Reports, statements, publications

Handling of external requests on air quality data

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Chap. 6 - Analytical Laboratory Air Quality

Inductive coupled mass spectroscopy (VARIAN ICP-MS 820)

Measurement of elements in dust and deposition dust

HPLC system Merck

Measurement of polycyclic aromatic hydrocarbons (PAH) in fine dust

Ion chromatograph Metrohm

Measurement of anions and cations in ambient air probes

Measurement of deposition dust and heavy metals content

Sampling of deposition dust

Digestion of dust and deposition dust for ICP-MS analysis

Chap. 7 – Air Quality Measurements by Passive Sampling

Air Quality Monitoring by Passive Sampling

The search for hot spots via passive sampler with respect to average NO2 exposure in an urban area

Evaluation of average benzene concentration by the use of passive samplers for the assessment of air quality according to EU Directive 2008/50/EC

Methods for measurement of Nitrogen Dioxide concentration in Ambient Air via Passive Sampler - Measurement method based on Saltzman Reaction

Determination of Benzene in ambient air via Passive Sampler

4

Guidelines for the Operation of the Air Quality Monitoring System

Content

1. Introduction ............................................................................................................ 5

2. Legal Framework ................................................................................................... 5

3. Tasks and Objectives of Air Quality Monitoring ............................................... 6

4. Quality Assurance ................................................................................................. 6

5. Organizational Foundations of the Guidelines ................................................. 7

6. Structure of the Guidelines for a Monitoring Network ..................................... 7

5

1. Introduction

The following guidelines were drawn up within the framework of the following

twinning-project:

Strengthening Administrative

Capacities for Implementation

of Air Quality Management

SR 07 IB EN 01

They describe the proposal of the twinning-experts with regard to the operation of the

network for air quality monitoring. They consist of recommendations, rules, standard

operation procedures (SOP) and should be used as a guidance for the operation of

air quality monitoring networks.

2. Legal Framework

The guidelines refer to the monitoring of air pollutants in the ambient air. The main

legal foundation in this regard in Europe are the CAFE-Directive 2008/50/EC and the

4th Daughter Directive 2004/107/EC of the Commission of the European Community,

which set limit values and guide values for each air pollutant. The European

directives with their mandatory implementation in the member states have led to

significant development on the legislative level but also to important technical and

analytical progress. The following criteria are to be mentioned as main focus:

Significantly severer limit values by implementation of the effect-oriented

standards of the World Health Organisation WHO

Extensive measures plans and action plans for the improvement of air quality

Extensive information of the public

Significantly higher demands with regard to the quality of air quality data and

to the quality management systems of the monitoring networks (Data Quality

Objectives of the EU Directives)

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3. Tasks and Objectives of Air Quality Monitoring

The air quality monitoring tasks may be basically divided in:

Area-oriented measurements: determination of the overall exposure to air

pollutants in different areas and its influence upon the population living there,

upon the vegetation and upon assets.

Local-oriented measurements: determination of specific exposure to air

pollutants in places with unusually high emissions and the sometimes limit-

value-exceeding levels of air pollutants deriving from it. (e.g. highly frequented

urban canyons)

Facility-oriented measurements: determination of specific pollution produced

by air pollutants from one or more industrial emitters.

The specific objectives of air quality monitoring according to EU Directives are the

following:

To verify whether the limit values and guide values set in the EU Directives are

being observed.

The analysis of reasons for high air pollution.

To control the effectiveness of the measures taken for air quality improvement.

To verify Dispersion Modelling for pollutants in the ambient air.

To determine temporal trends with regard to air pollutant levels.

To investigate long range transport of air pollutants.

4. Quality Assurance

As a rule, the metrological air quality verification is regulated by state provisions,

which mainly rely on European Directives, and takes place according to state-

acknowledged standards and guidelines. Reference to this will be made in some

instances in the present guidelines. The quality assurance measures for the

investigation of air quality refer to the following levels of action:

Specifications with regard to the monitoring strategy i.e. definition of task,

choice of monitoring location, monitoring period, etc.

The use of verified monitoring equipment, the use of reference and

equivalence procedures.

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Proof of calibration procedure traceability to National Standards.

Confirmation of professional competence through accreditation of laboratories

and monitoring networks by an accreditation body with European recognition

Quality control of monitoring stations and networks by means of national and

international interlaboratory tests, audits and quality management systems

The guidelines provide valuable support for many of these points, in order to reach

quality targets and to be able to provide the European Commission with reliable data

on air quality.

5. Organizational Foundations of the Guidelines

The guidelines mainly refer to European EN standards and Directives, that will not be

detailed here, but that will be referred to in particular cases. There will also be

reference to the operating instructions of the individual devices of the monitoring

network.

In the SOPs the operation of regional monitoring networks will be taken as a basis.

The national level will only be referred to. This means that neither the function of the

National Data Centre (for the provision of EoI requirements) nor that of the National

Reference Laboratory will be described.

6. Structure of the Guidelines for a Monitoring Network

The guidelines comprise all important tasks which belong to the operation of air

quality monitoring networks according to the EU Directives for air quality:

Guidelines for the measurement strategy of air quality

Regulations for the operation of the monitoring network

Regulations for the work of the calibration laboratory

Regulations for the network data centre with regard to data collection, the

database for measured values, the data validation steps and several aspects

on reporting.

Guidelines for important tasks of the analytical laboratory air quality

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Guidance for air quality measurements by passive sampling

The steps in the quality assurance process are comprised in the guidelines for

operation and maintenance of the stations, as well as in the European standards they

have been based upon.

The guidelines can be divided as follows:

Structure of the air quality monitoring system

Guidelines measurement strategy

Guidelines concerning the operation tasks of the monitoring network

Guidelines concerning the tasks of the calibration laboratory

Guidelines concerning the tasks of the network data centre

Guidelines concerning the tasks of the analytical laboratory air quality

Guidelines concerning air quality measurements by passive sampling

A complete list of all documents included in this Guideline ―Ambient Air Quality Monitoring Network‖ is given in the content.

Concept of the Air Quality Monitoring Network

Content

1. Structure of the Air Quality Monitoring Network ............................................ 9

2. Tasks description of the monitoring fields ................................................... 10

3. Quality Management in Air Quality Monitoring ............................................. 13 3.1 Traceability of air quality data ..................................................................... 14 3.2 Linearity test ............................................................................................... 14 3.3 Receiving inspection .................................................................................. 14 3.4 Type approval test for suitability evaluation on site .................................... 16 3.5 Reference standards for physical measures .............................................. 16 3.6 Gravimetric analysis ................................................................................... 16

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1. Structure of the Air Quality Monitoring Network

Flow Chart of Assumptive Structures National Level Regional Level * = No. Acad./Eng./Techn.

Local Level

Monitoring network

service

1/1/4

Calibration lab and

analytical lab

1/3/3

Monitoring network centre

1/1/1

Monitoring Network

1/0/1*

Maintenance

Repairs

Calibration

Test gases bottles

Test gases

Transfer standards

Gravimetric

analysis

Evaluation of

measurement

devices

Balance manual

National

Reference

Laboratory

Modelling National Data

Centre: EU-

Reporting,

national

information

.........

Data control and

release

Validation

Calculation of

statistical parameters

Data Analysis and

Assessment

Reporting

Data dissemination

Information of the

public

Station operation:

Fault-clearance service

Maintenance work

Security aspects

Information of the population

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2. Tasks description of the monitoring fields

Regional Level: The monitoring network is headed by a scientist/academic, to whom an assistant is assigned. The monitoring network service is led by an academic and also comprises one engineer and 4 technicians. Their tasks are the following: Task description: Academic Managing, monitoring strategy, personnel management and budget Engineer Start-up verifications Adaptation of new devices to the monitoring network Training of technicians Procurement (devices, spare and consumable material) Location planning and arrangement

Responsible for transfer standards and their verification in the calibration lab

Control of completed calibrations Technician Maintenance and repairs Calibrations

According to qualification divided into maintenance technician and repair technician.

The Laboratory belonging to the monitoring network is composed of the two units:

- Calibration lab - Analytical lab for inorganic and organic air pollutants

The laboratory is led by an academic. He has three subordinate engineers with the following assignments:

- Calibration lab (reference equipment for SO2, NO, NO2, O3, CO, benzene, particles; gravimetric analysis PM10 and PM2,5; transfer standards; calibrations and linearity verifications for new and repaired equipment

- Analytical lab for inorganic air pollutant components: Pb, Cd, Ni, As, Hg and other heavy metals; inorganic components in dust and deposit.

- Analytical lab for organic air pollutant components: BTX, PAH, Benzo(a)Pyrene, rust; if necessary: Furan, Dioxin

Task description: Calibration lab engineer Chemistry, physics, electronics Engineer Analytical lab/inorg. Focus on inorg. chemistry, AAS, ICP/MS Engineer analytical lab/org . Focus on org. chemistry, GC, HPLC General: quality management, determination of measurement uncertainty, procedure development, participation in interlaboratory tests, laboratory comparisons.

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The monitoring network centre is headed by an academic and also comprises one engineer and a technician. Their tasks are the following: Task description: Academic Management of the data centre

Planning/further development of database and data communication Further development of data validation procedures Reporting

Engineer Administration of network of monitoring network Data validation Data assessment Preparation work for reporting

Data dissemination according to requirements (EU-requirements, requests from municipalities, research, media)

Technician Computer maintenance, data transfers, database, support with data validation, assessment, reporting

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Local Level: On this level, the „air quality‖ unit takes on the tasks of caring for the monitoring network in the monitoring department. This unit is led by an engineer, who mainly organizes the support for stations and takes on the data assessment on local level as well as information of the local public. He is accompanied by 1-2 technicians who are responsible for fault clearance, maintenance work and the overall operation of the stations. The number of necessary employees depends on the number of the attended stations; as indicative number one technician can be calculated for every three stations. Task description: Engineer Organization of monitoring station

Data assessment/ collaboration in Clear Air Plans and action plans Information of the local public, municipalities, businesses, media, schools, action groups, etc. Support of monitoring network service in special investigations (e.g. in the framework of approval procedures, road planning, specific land-use areas, industrial parks, regional planning procedures) Special programmes for the determination of PM-10 pollution

Technician Maintenance: exchange of all consumable material

Repairs: exchange of worn out pieces (Pumps, membranes, magnet valves). First fault diagnosis until the decision is taken, whether the devices needs to be exchanged. Support with Public Relations

The tasks of the regional and local levels need to be defined very accurately. Experience has shown that otherwise responsibility in case of malfunctions is critically.

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3. Quality Management in Air Quality Monitoring It is stringent to establish a Quality Management System (QMS) for the air quality monitoring. This system must comply with EU regulations and must be implemented at the same time with the installation of the air quality monitoring networks. For each air quality monitoring network, the QMS is vital, because very important decisions regarding air quality monitoring, legislation against emission source operators depend totally or partially on the measurement data. Not only are incorrect data and false information useless, but they can lead to wrong decisions and endanger human health. The QMS should comprise the following elements:

Selection of measurement locations Selection of measurement devices used Calibration of measurement devices (monitors) Maintenance of monitors and monitoring stations Management of measurement data Validation of measurement data

A good data quality and a high data capture rate are essential in an air quality monitoring network in order to reach the Data Quality Objectives (DQO) of the EU Directives. In order to ensure that the data are sufficiently accurate, reliable and comparable to other monitoring networks, the measures for quality management have to be consistently used in the entire network. The QM-System has the following fundamental objectives:

The measurement data of the network must be representative for existing air pollutions in the monitored (urban) area.

The measurement must be accurate, precise and traceable. The measurement data must be comparable and reproducible: the results of a

geographically extended area must be consistent and comparable to international standards.

The measurement results over the entire period of the monitoring network operation must be consistent (consistent over time).

The basics for the measurement are the primary and secondary standards, which are usually cared for by the National Reference Laboratory (NRL). Additionally, there are the necessary absolute or traceable metrological standards, for which the National Metrological Institute is responsible (temperature, pressure, flow rate, weight, etc). The necessary requirements for the achievement of uniformity are:

The used measurement methods must be known (known performance) and their scope must be defined.

Each calibration must be traceable by means of an uninterrupted string to international standards.

The measurements must be performed within a documented QMS. Because of the importance of these general requirements for the measurements in an air quality monitoring network, the main tasks of the regional calibration laboratories (RCL) are described in more detail in the next pages.

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3.1 Traceability of air quality data The regional calibration labs (RCL) have many diverse tasks. One of the main tasks is the supply of traceable transfer standards for the calibration of measurement devices in the monitoring networks.

Traceable means, that these transfer standards are connected to national/international standards by an uninterrupted chain of comparison measurements with known measurement uncertainty.

National standards shall be kept by the National Reference Laboratory (NRL) and shall be linked to international standards by means of international comparison measurements.

The laboratory reference standards used in the calibration labs as a basis for calibration have to be certified by the NRL by means of comparison measurements with the national standards. The uncertainty of the certified test gas concentration shall always be indicated in this process.

Both test gases in test gas bottles and test gas generators can be used as laboratory reference standards. The stability of the laboratory reference standards used must be monitored constantly by the Reference Calibration Labs by means of appropriate measures (e.g. cross-checks with a second standard or independent procedures).

The calibration labs perform comparison measurements of the transfer standards with the laboratory reference standards and determine their uncertainty. To this purpose, reference measurement devices are used, which have been previously calibrated with the laboratory reference standards. Then, the transfer standards are deployed in the monitoring stations for the calibration of measurement devices. Thus, the traceability of air quality data to national standards is guaranteed.

Additional to reference standards, the RCL‘s also have other standards at their disposal (laboratory work standards), which can be used, for example for the daily zero/span control of the reference measurement devices and for the linearity test of measurement devices.

3.2 Linearity test

The linearity of measurement devices is to be tested regularly, yearly or every three years, according to test results. Also, after repairs or basic maintenance works on measurement devices, a new linearity test shall be necessary.

With newly procured measurement devices the linearity test shall take place in the RCL before its installation in a monitoring station.

3.3 Receiving inspection The EN ISO/IEC 17025 „General requirements for the competence of testing and calibration laboratories― requires that newly acquired measurement devices are tested for the observance of technical specifications and for compliance with the requirements of that particular measurement procedure. These receiving inspections shall take place in the RCL.

The receiving inspection for new measurement devices comprises a formal part, in which the completeness of delivery is checked and a practical part, in which data transfer, device parameterisation and the compliance with special performance

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characteristics are checked. The basic calibration and the first linearity test shall also take place in the framework of the receiving inspection. Only if the measurement device fulfils all requirements it may be cleared for measurement use.

The results of the inspection and the approval of measurement devices are to be documented.

The following scheme shall again make clear the tasks described above:

National Standards

(NRL)

Laboratory Reference

StandardsTransfer Standards

Laboratory Working

Standards

Reference Analyser

Analyser

com

parison

measure

ments

calib

ration

calibration

initia

l checks

Lack o

f F

it c

heck

measurement

zero

/span

check

certification

cert

ific

ation

basic

calib

ration

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3.4 Type approval test for suitability evaluation on site

The European standards for the measurement procedures for SO2, NO/NO2, O3 and CO require that before use a measurement device be tested for its suitability to fulfil the requirements of EU Directives regarding data quality even in the specific conditions of the envisaged measurement site. For this, the measurement uncertainty of the measurement device is calculated taking into consideration the results of the type approval test and the specific conditions of the measurement site and then compared with the requirements regarding measurement uncertainty of the EU Directives.

The task of performing the type approval test for suitability evaluation shall be fulfilled in the RCL‘s. A close collaboration between calibration lab, monitoring network service and monitoring network centre shall be necessary in order to determine the starting values required for the calculation of measurement uncertainty.

All calculations shall be documented

3.5 Reference standards for physical measures

In the monitoring network service volume flows, from PM10 samplers for instance, as well as pressure and temperature sensors have to be verified regularly.

The balances used for the gravimetric determination of PM10 shall be calibrated regularly with reference weights.

The RCL‘s must have at their disposal calibration reference measurement devices and certified reference weights for the measures volume flow, pressure, temperature and mass and must organise and ensure their regular recalibration or metrological verification by the NMI.

These reference measurement devices shall be used in order to calibrate the measurement devices used for the tests in the stations and the balances.

3.6 Gravimetric analysis

The RCL‘s are responsible for the gravimetric determination of PM10 and PM2,5. For this, they have air conditioned balance rooms for filter conditioning and weighting.

The course of action and the requirements for the gravimetric determination of PM10 and PM2,5 are described in the corresponding European standards (EN 12341 and EN 14907).

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Measurement Principles and Measurement Methods

Content

Measurement Principles and Measurement Methods .............................................. 17

1. Discontinuous methods .......................................................................................... 18

2. Continuous Measurements ..................................................................................... 18 2.1 Suitability Tests .................................................................................................... 19 2.2 Description of Continuous Ambient Air Measurement Equipment ........................ 19 2.3 Measurement Principles ....................................................................................... 19

2.3.1 Conductometry ............................................................................................... 19 2.3.2 Chemiluminescence Measurement ................................................................. 20 2.3.3 UV Fluorescence Measurement ..................................................................... 20 2.3.4 Measurement of UV Absorption ...................................................................... 21 2.3.5 Flame lonisation Measurement ....................................................................... 21 2.3.6 Optical Long-Path Monitoring (Path-Integrating Measurement) ...................... 22 2.3.7 Automated Gas Chromatography ................................................................... 22 2.3.8 Measurement with Beta-Ray Absorption ........................................................ 23

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Measurement methods for ambient air quality measurement are usually divided into - discontinuous methods and - continuous methods.

1. Discontinuous methods

Discontinuous methods are mostly manual methods for which sampling on site and analysis in the laboratory are two separate steps. Continuous methods typically involve automatic equipment at a fixed site to carry out both sampling and analysis. However, these distinctions do not quite take account of the great variety of air quality measurement methods. "Discontinuous" measurements can be carried out with automatic equipment at the sampling site as well as in the laboratory. The employment of automatic sampling equipment - e.g. with several, independently and subsequently controllable absorption receptacles - allows continuous and uninterrupted measurements. Analyses can be carried out with an automatic apparatus in the laboratory. One specific example is the measurement of dust deposition. This is in principle a discontinuous, manual measurement method, but because of the length of the exposition time of one month without breaks for a single measurement, it is termed semi-continuous. Continuous measurements have the advantage of providing temporarily unbroken air monitoring. They are predestined for stationary employment, but it is also possible to fit them in mobile monitoring laboratories. Since higher temporal than spatial variation is to be expected for air pollution in city areas with widely distributed pollutants - such as SO2 -, continuous measurements provide advantages for air quality monitoring. For the implementation of Smog Regulations continuous measurements are indispensable. Expenditure for automatic continuous measurements is high: the measurement equipment is quite expensive and highly qualified personnel is needed for its operation. Therefore, equipment for continuous ambient air quality measurements has been developed so far only for a limited number of substances. Discontinuous, manual ambient air quality measurement methods are most useful for random sampling, and for covering many measuring sites in an examination area. Often, the measurements apparatus can be employed for the detection of several different substances. Finally, this working area covers the measurement of all those substances for which no automatic equipment is available.

2. Continuous Measurements

Continuous ambient air quality measurements are carried out mainly for the implementation of government regulations in particular of the European Community. The German law specifies that listings of suitable measurement equipment for continuous measurements shall be published by the Federal Minister for the Environment, Nature Protection and Nuclear Safety (BMU) following consultation with the responsible authorities of the individual Federal States. These publications shall be made in the Joint Ministerial Gazette.

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2.1 Suitability Tests

The publication of suitable equipment for continuous ambient air quality measurement by the BMU requires the successful completion of a suitability test. An examination schedule for suitability tests, which has been designed by experts of official Federal and local government institutions and has been approved. A suitability test is normally carried out following a request by the measurement equipment manufacturer to one of the institutes named above. On completion of the suitability test, which is carried out at the manufacturer's expense, the institute provides a test report to the Federal Environmental Agency (UBA). If their assessment is positive, publication follows as mentioned above in the Joint Ministerial Gazette by the Federal Minister for the Environment, Nature Protection and Nuclear Safety (BMU). 2.2 Description of Continuous Ambient Air Measurement Equipment

Detailed descriptions of quite a number of continuously operating ambient air quality measurement devices can be found in Guidelines by the Commission on Air Pollution Prevention in the Association of German Engineers (VDI/DIN). These Guidelines describe continuously operating measurement devices for the measurement of sulphur dioxide, nitrogen oxide, carbon monoxide, ozone, sum of organic compounds and suspended particulate matter. 2.3 Measurement Principles

Suitability-tested, continuously operating ambient air quality measurement devices are available for the following air polluting substances: - sulphur dioxide, - nitrogen oxides, - carbon monoxide, - ozone, - total gaseous organic compounds, - benzene, - toluene, ethyl benzene, xylene and - suspended particulate matter, PM10, PM2.5. The measurement principles employed by these instruments are briefly described in the following. In most cases they correspond to the methods used for continuous emission measurements so that the descriptions have partly been borrowed from the Emission Manual.

2.3.1 Conductometry

In the conductometric measurement principle the sample gas is introduced into a suitable liquid reagent and the change of the conductivity is measured after completion of the reaction between the liquid and the gas. Objects of measuring are mainly sulphur dioxide and carbon monoxide. In continuous conductometry the sample gas and the reagent liquid are continuously delivered into the reaction cell. As the conductivity is dependent on the ratio of sample gas to the liquid volumetric flow, suitable means must be provided to ensure

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that the flow of both streams is kept constant. The influence of temperature on the conductivity must be compensated.

2.3.2 Chemiluminescence Measurement

Some chemical gas reactions produce a characteristic radiation, the so-called Chemiluminescence. The intensity of this Chemiluminescence is proportional to the mass flow rate of the sample gas under constant reaction conditions, if the auxiliary gas necessary to produce the reaction is present in excess. The Chemiluminescence emitted during the oxidation of nitrogen oxide molecules with ozone is used in the determination of NO concentration: NO + O3 —¥ NO2 + O2 + hv. Chemiluminescence measurements take place in a reaction chamber. Air which has first passed through an ozone generator flows into this chamber. The partial conversion of the oxygen in the air to ozone is accomplished by electrical discharges or by UV irradiation. A constant flow sample gas enters the reaction chamber via another entrance nozzle and is mixed with the ozone rich air. An ozone filter is fitted in the outlet of the reaction chamber to prevent pollution of the environment. The chemiluminescence, after being optically filtered, is measured with a photomultiplier. A thermostatically temperature controlled reaction chamber operating at a constant internal pressure is absolutely necessary to obtain a stable measurements. For the determination of the nitrogen dioxide concentration, the sample gas is first passed through a thermocatalytic converter which reduces NO2 to NO before the analysis is performed. This method is also used to measure ammonia in ambient air. For this purpose, NH3 is transformed into NO, and the amount of NH3 in the sampling air is determined by measuring the difference to the previous amount of NO. The principle of chemiluminescence is also employed for ozone in ambient air quality measurements (Table 7). Here also the reaction of O3 and NO (in excess) described above is used for continuous measurements.

2.3.3 UV Fluorescence Measurement

The sample air passes through a beam of light from a UV lamp (e.g. Zn-hollow cathode lamp). As a result the molecules of the gas to be measured are activated into a fluorescence radiation which is led into a photomultiplier as a receiver and can be measured after amplification. An interference filter placed before the receiver filters out the specific fluorescence radiation of the gas to be measured. The fluorescence intensity is a function of the concentration of the gas to be measured and the light energy of the UV light source. The method is employed as an ambient air quality measuring technique for the continuous measurement of sulphur dioxide. It also enables the measurement of hydrogen sulphide. Before the measurement H2S is oxidized to SO2. Measurement by Non-Dispersive Infrared Absorption and Gas Filter Correlation All heteroatomic molecules like CO, CO2, SO2 and NO possess a typical characteristic absorption spectrum in the infrared range. In ambient air quality measurement, the principle of infrared absorption is employed exclusively for the measurement of carbon monoxide (CO) and carbon dioxide (CO2), because the

21

radiation absorption of these gases is high enough even in low concentrations in atmospheric air. The non-dispersive infrared absorption methods (NDIR) dispense with the spectral refraction and obtain the desired selectivity by the use of a sample of the measuring component stored in the instrument itself. Depending on the method of storing the sample, the non-dispersive infrared absorption method (NDIR) and the gas filter correlation method (GFC) are distinguished. The NDIR method uses the light receiver for storage. The radiation transformed in the gas filled receiver chambers and modulated by a revolving chopper wheel produces periodic pressure variations in the receiver chambers. These are sensed, either by a membrane capacitor, or in a micro flow detector which senses the pressure equalizing flow between each of two receiver chambers, and converted into electrical signals. The gas filter correlation (GFC) method uses a gas filled chamber fixed to a filter wheel. This filter chamber and either an opening or a N2 gas filled filter are alternately and periodically brought into the light path.

2.3.4 Measurement of UV Absorption

UV absorption measurement is employed for continuous measurements of ozone in ambient air. The measurement is based on the absorption of ultraviolet light by ozone, which has a maximum wavelength of 254 nm. The sample air is passed into a measurement cell, which is placed between the UV radiation source and the radiation receiver (i.e. a photomultiplier). The air is passed into the cell by means of a magnetic valve alternating between direct flow and flow through a catalytic converter, which quantitatively reduces ozone to oxygen. The radiation intensity measured in ozone free air is stored and subtracted from the intensity measured in the air containing ozone.

2.3.5 Flame lonisation Measurement

Organic carbon compounds are relatively easily ionizable in a hydrogen flame. In an ionization chamber the ion cloud thus produced is extracted by applying an electric field via electrodes and generates an electric current. This current is, to a large degree, approximately proportional to the mass flow rate of organic bound carbon atoms. There is, however, a certain dependence on the structural bond of the C atoms of the particular molecule. The flame ionization detector consists of a combustion chamber. Pure hydrogen, which can be taken from a pressurized gas cylinder or produced in an electrolytic hydrogen generator unit, flows through a nozzle into the combustion chamber. Combustion air from the atmosphere is admitted via an annular slit around the nozzle. After electrical ignition, a steady hydrogen flame produces a very small ion density (zero value) in the absence of organic carbon compounds in the sample gas. The electrodes necessary to extract the ion cloud are arranged near the flame. The combustion nozzle itself can be used as one of the electrodes. With a sufficiently high electric potential difference, all the charge carriers will find their way on to the electrodes, i.e., the saturation current is flowing. This is raised to the desired signal amplitude by a sensitive direct depends on the material of the combustion nozzle and

22

the detector geometry. For continuous measurements the temperature and the mass flow rate of the sample gas must be kept constant. For ambient air quality measurements, the determination of the sum of gaseous organic compounds is current amplifier, and at the same time, the zero value is compensated. The absolute measuring sensitivity performed after the separation of methane, which is always contained in samples but hygienically negligible. The separation can be obtained by placing before the FID either a short separation column or a cooled storage column or by catalytic burning of hydrocarbons, taking advantage of the fact that they have a larger mass than methane.

2.3.6 Optical Long-Path Monitoring (Path-Integrating Measurement)

Optical long-path monitoring techniques for air quality monitoring have already been used for years for various measuring tasks, particularly for the registration of emission rates and for air-chemical as well as meteorological research. The following optical techniques for gas long-path monitoring are designated and described: - Lidar - Derivative Spectroscopy - Differential Optical Absorption Spectroscopy (DOAS) - FTIR-Spectroscopy (Fourier-Transformation-Infra-Red) - Correlation Spectroscopy. Optical long-path monitoring does not include sampling by suction of air. This measures the radiation absorption which occurs when a defined beam passes through an air distance of the gas to be analysed. Long-path monitoring is usually closer to emission measurements than to ambient air quality measurements. The pollution concentrations close to emission sources is often measured. Detection limits and interferences caused by fog, dust and other substances limit the use of long-path monitoring for ambient air quality measurements. The optical long-path monitoring technique (DOAS) is based on the absorption of UV light or visible light by the gas to be measured on a length up to several kilometers between a light emitter and a receiver system. It proved efficient for ambient air quality measurement as for instance by the suitability test of an instrument for measurement of sulphur dioxide. Instruments for measuring nitrogen oxide, ozone and benzene are currently undergoing suitability tests.

2.3.7 Automated Gas Chromatography

The principle of gas chromatography is also used in new suitability tested devices for continuous-automatically measurement of aromatic hydrocarbons (benzene, toluene, xylene, ethyl benzene) in ambient air. Minimum requirements and examination for devices measuring automatically for individual measurements of benzene in air with enriched sampling and subsequent gas-chromatographical separation are described in the DIN-norm 33963-2. Particularly the measurement of benzene as an air-hygienically critical component of motor vehicles' exhausts is a priority of air quality supervision today.

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2.3.8 Measurement with Beta-Ray Absorption

In dust measurement with beta-ray absorption systems, the sample air is sucked through a filter tape which is getting moved stepwise. The dust quantity precipitated on the filter tape is measured by the gradual attenuation of the beta-ray radiation that is passing through the dust laden filter. A synthetically manufactured radioactive probe of suitable activity (e.g. carbon 14 or krypton 85 isotopes) is used as the radiation source and a Geiger-Müller counter or an ionisation chamber employed for the detection. To compensate for the gradual reduction in radioactivity over a period of time and the variation of the radiation weakening due to the filter material, measurements of the absorption are taken before and after, or before and during dust filtration and the measured values compared with each other. During the absorption measurement, while dust sampling, the accumulated particle mass is measured and indicated. Generally, the double-beam compensation method is employed in devices of this kind. This facilitates a real-time measurement of dust on the filter.

Planning of ambient air quality measurements

General rules

Contents 1 Problem analysis 1.1 Content of the task description 1.2 Analysis of background information 1.3 Assessment of the results of the measurements 1.4 Measurement parameters, measurement area and measurement period 1.5 Requirements on the results 2 Organization 2.1 Project management 2.2 Personnel planning 2.3 Scheduling 2.4 Subcontracts 3 Measurement techniques 3.1 Time resolution of the measurements 3.2 Performance characteristics 3.3 Standardization of the measuring procedure 3.4 Infrastructure for using measurement techniques 3.5 Data recording and documentation of the measurements 4 Measurement strategy 4.1 Measurement locations 4.2 Measurement times 4.3 Sampling period 4.4 Duration of the measurement program 4.5 Supplementary measurements 5 Evaluation 5.1 Producing measured values 5.2 Evaluation algorithms 5.3 Measurement uncertainty 5.4 Uncertainty of the result

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6 Quality assurance 7 Reports 1 Problem analysis The intention of the requirements described here is for the planning of ambient air quality measurements to be completed so as to enable a given task description to be processed with sufficient conclusiveness and with an acceptable outlay. This should ensure that the results gained from the measurements will meet the requirements stipulated in terms of the data being representative and with regard to the measurement uncertainty. This is an aid to everyone involved in the planning, performance or evaluation of ambient air quality measurements. Basic knowledge in the following fields is useful: - assessment of air pollution and its effects, - chemistry of air, - measurement techniques in the field of trace analysis, - meteorology, - statistics, - quality assurance. The aim of problem analysis is to differentiate the investigation task so that appropriate and

unambiguous technical stipulations can be defined for carrying out the investigations. In order

to do so, the following must be analyzed:

- what objective is to be achieved, - what background information concerning the problem is available, - how the results of the measurements are to be assessed, - which air quality characteristics, which measurement area and which measurement period are to be studied. 1.1 Content of the task description A specific task description is required in order to plan the measurements. The task is considered to be described with sufficient clarity if it allows stipulations to be made concerning the following points: - air pollutants to be investigated, - assessment standards to be applied, - measurement techniques, including sampling, - measurement area and density of measuring sites or measurement locations, - duration of an individual measurement, frequency and period of measurement, - quality assurance, - evaluation and report. 1.2 Analysis of background information The problem analysis phase includes gathering information which will allow classification of the task. Before a measurement task is formulated, a model concept is usually developed to determine a causal relationship between the occurrence of air pollution at a location or within an area under consideration and its possible effects on a group of objects to be protected or an individual from such a group. The extent to which a planned investigation using techniques to measure the respective air pollution in the atmosphere can help to answer the question raised will depend, among other things, on how realistic this model concept is. It can be used to analyze

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how the problems presumably caused by air pollution in the area in question can be described adequately and how they can be investigated using measurements and whether an investigation task requires further detailing. Starting points for the analysis are matters concerning measurement data available, sources which contribute to the occurrence of air pollution within the measurement area, and effects on the objects to be protected. Analysis of measurement data available If results of surveys on air pollution carried out within the measurement area are available, they may provide important information for the planning of further measurements. If the measurement area contains one or more permanent measuring stations, these should be taken into account when planning the measurements. The measurements recorded by these permanent measuring stations may be included in the evaluation. The same applies to any meteorological data available. Analysis of the sources To determine the air pollution occurring within the measurement area, it may be necessary to carry out an analysis of the sources present within the measurement area and its vicinity and of the emissions from such sources. This requires expert knowledge in plant and process engineering. In this context, it may also be helpful to analyze any emission survey charts which may be available. Generally the following types of sources are distinguished: - industrial facilities, - small industry and house fires, - traffic, - natural sources. Any sources of emissions with a low outlet or stack height are extremely significant for the occurrence of near-ground air pollution within a measurement area. Sources with higher stacks contribute to a lesser extent to the occurrence of near-ground air pollution near to the source owing to the greater dilution of the emissions on their dispersion paths. In many cases, dispersion calculations can be applied to estimate the anticipated proportions from known sources in the air pollution within the measurement area. Provisions covering such calculations are laid down in pertinent guidelines and procedures. The result of these analyses should be a register of types of air pollution anticipated. Information on the sources or types of sources causing the pollution should be included in the register. Effects of air pollution When planning the measurements, it is also useful to know what effects may be caused by air pollution on objects to be protected and what hazards may be involved. The following outline will show how important this is. A precondition for the effect of air pollution on an object to be protected is firstly the contact of the object with the air pollutants. Such a contact can take place either directly by direct exposure or indirectly (however, the indirect effect of trace substances relevant to the climate, for example, will not be examined here). In the case of man as the object to be protected, there is direct contact, e.g. by inhalation and additionally through unprotected skin, as well as indirect contact which is mainly through the food chain. In contrast to indirect contact over which man has a certain amount of control by suitable preventive measures (control and selection of food), it is generally very difficult to apply acceptable measures to prevent direct exposure when the substance

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has already escaped into the atmosphere. Since effects are usually determined by the mass of a substance absorbed, the duration of exposure and the pattern of exposure over time, the differences mentioned may be significant when stipulating the measurement strategy to assess the impact of a pollution situation. Additionally, in the case of direct exposure, consideration should be given to the fact that the different pollutants can have different effects on the objects to be protected. For instance, acute effects may occur due to the effect of high concentrations of particular substances (e.g. irritant gases such as ozone, sulfur dioxide or nitrogen dioxide), and chronic effects may occur due to an accumulation of possibly extremely low concentrations of various substances (e.g. heavy metals such as lead or cadmium). As far as measurements are concerned, the carcinogenic substances (e.g. benzene, benzo(a)pyrene or asbestos) shall be treated in the same way as the cumulative substances. Such aspects should therefore also be taken into account when stipulating measurement strategies. 1.3 Assessment of the results of the measurements International and national assessment standards are derived from the information gained concerning interrelations between exposure and observed effects. For instance, assessment standards are included in national environmental legislation with the associated Regulations and Administrative Orders and in corresponding Executive Orders. The assessment standards include, for example, action values, threshold values, test values and recommended values. The applicable assessment standards form the basis to derive air quality characteristics which are to be determined within the framework of the measurements. 1.4 Measurands, measurement area and measurement period The problem analysis shall include verifying whether the measurands to be collected, the measurement area and the measurement period have been stipulated in an unambiguous and targeted manner. In doing so, any appropriate environmental provisions shall be observed. In this context, it should now be clear what supplementary information (e.g. results from preliminary investigations) is required to carry out the investigation task. 1.5 Requirements on the results During the detailing of the task description, stipulations shall be made with regard to the air quality characteristics (characteristic values) to be determined, the requirement on the measurement uncertainty, and the requirement on how representative the measurements are to be in terms of area and time. It is important to stipulate these boundary conditions since they have a major influence on the outlay required for the measurements. Reference shall be made to pertinent standards and guidelines if these can be applied to specify the above requirements. 2 Organization 2.1 Project management The person appointed as project manager shall have the knowledge and practical experience required for planning and carrying out ambient air quality measurements. A suitably qualified deputy project manager shall also be appointed. Verification of their qualification may be provided.

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2.2 Personnel planning Planning of the personnel resources required to carry out the measurements shall depend on the measurement task set. The personnel shall have relevant experience with the measuring procedures used. Measurement technicians and their assistants shall have acquired their knowledge through practical work in the field of air quality measurements. A technical qualification and knowledge of electronics and computers are an advantage. 2.3 Scheduling Planning and organizing the schedule to carry out the measurements will depend on the measurement strategy and the measurement procedures. The time sequence shall be documented. In the case of measurements based on random samples, alternative dates shall be planned for the event of any measurement gaps. 2.4 Subcontracts Subcontracts should only be awarded for precisely defined tasks. The qualification of the subcontractors to carry out the task shall be verified by provision of documented evidence (e.g. quality assurance manual. Any subcontractors participating in a measurement contract shall be specified in the measurement plan.

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3 Measurement techniques With regard to the measuring procedures to be used, stipulations shall be laid down concerning sampling, analytical determination and data production. The measuring procedures will be selected in accordance with the measurement task. The results of the measurements must meet the requirements set. When selecting the measurement techniques, the following points shall be examined in particular: - Will the required temporal differentiation be achieved using the measuring

procedure? - Are the performance characteristics of the procedure sufficient with regard to

the task description? - Is a standardized measuring procedure required for the measurement task? - Can the infrastructure necessary for the measurements be provided? - Is the measuring procedure sufficiently documented? Continuous measurements comprise uninterrupted recording of air pollution throughout the measurement period (apart from interruptions for calibration, servicing, etc.). If automatically recording measuring instruments are used, sampling, analytical determination and data production can be carried out in situ. In these cases, the data is recorded using line recorders and/or data-recording computers and memories. Any non-recording measuring instruments are usually used for supplementary procedures, and the measurements need to be evaluated in the laboratory at specific intervals. Discontinuous measurements provide individual, non-connected measurement data (measurements of random samples). Therefore they do not provide full information throughout the measurement period. The number and times of measurements of random samples shall be selected to correspond to the measurement strategy stipulated and to meet the requirements set for the results of the measurements. For many measurement tasks, it is customary to stipulate the number and temporal distribution of measurements of random samples giving due regard to the statistical uncertainties involved. Semi-continuous measurements exist, according to the above definition, if the results of discontinuous measurements do not differ by more than 5% from the results of the theoretically correct, continuous measurements over the reference period. In the case of different air pollutants, the requirements may vary greatly and will be dependent on the respective time constant with which the concentrations may rapidly change. Measurements will be semi-continuous in cases where a discontinuous measuring procedure is used to carry out measurements which as far as possible are continuous over the relevant period. With the aid of automatic measurement techniques (robots), it is now possible to convert some discontinuous measuring procedures into semi-continuous procedures at an acceptable effort, e.g. by automatic exchange of the sampling medium (accumulation material) and subsequent on-the-spot evaluation (e.g. benzene). For this purpose, a particular time cycle can be specified for the individual measurements up to continuous recording. 3.1 Time resolution of the measurements

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The time resolution of the measurements shall be in accordance with the air quality characteristics to be determined. For continuously recording measuring instruments, the time periods can be divided up on a broadly variable basis. These will not provide genuinely instantaneous values. The shortest possible integration time will depend on the measurement arrangement, the response time of the instruments, the sampling cycle, etc. In the case of measurements taken by non-continuously recording instruments, the time resolution will be determined primarily by the type and duration of sampling required to achieve given performance characteristics of the procedure, above all in this case, the detection limit.

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3.2 Performance characteristics The requirements for the performance characteristics of the measuring procedure to be used (e.g. detection limit, confidence range, cross-sensitivity) shall be based on the assessment standards and on the level of the concentrations or deposits anticipated. The detection limit of the measuring procedure should in any case be less than 10 % of the assessment standard. This must be ensured with acceptable outlay in terms of quality control and documented in a reproducible manner. The frequency and scope of calibration required shall be stipulated in the measurement plan. The reference materials, reference measuring procedures and test gases to be used shall be specified. The performance characteristics specified for standardized measuring procedures in guidelines and standards and in suitability test reports for measuring instruments can be used as a guide when selecting the measuring procedure. The analytical function of the measuring procedure used shall be verified at regular intervals. When using non-standardized measuring procedures, the performance characteristics shall be redetermined whenever the operating instructions are amended. The performance characteristics shall be recorded accurately and attached to the reports of the results. 3.3 Standardization of the measuring procedure To guarantee uniform practices in the monitoring of ambient air quality throughout the Federal Republic of Germany, stipulations relating to measuring procedures and measuring instruments are set out in general Administrative Orders. Standardized measuring procedures are listed in the 4th Administrative Order on Air Pollution Control. Continuously operating measuring instruments shall meet minimum requirements and this shall be verified in comprehensive suitability tests at an approved test institute. The performance characteristics and possible applications shall be documented in the test report. Lists of approved measuring instruments will be published in the Joint Ministerial Gazette by the relevant ministry in agreement with the supreme state authorities responsible for air pollution control. Wherever there are appropriate guidelines or standards, only standardized measuring procedures should be applied. The documentation shall include the name, origin and number of the guideline or standard. If no standardized measuring procedures are available, the measuring procedure used shall be documented in a comparable manner. Methods and operating instructions shall be prepared giving sufficient detail to ensure that the sequence of the investigation can be retraced precisely at any time. The performance characteristics shall be redetermined whenever the operating instructions are amended. The operating instructions shall be numbered and kept in the archives. 3.4 Infrastructure for using measurement techniques For the measurement techniques to be employed, a specific infrastructure must be available or be able to be provided with acceptable outlay. In this context, the following aspects shall be examined: - Is there a guaranteed energy supply to meet requirements (e.g. secure against

being switched off or against power failure if supplied by a third party)?

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- Are the measuring procedures affected by the weather (temperature, humidity, sunlight, frost), and is there a suitable measurement location available e.g. air-conditioned measuring room or vehicle, if required?

- Are the measuring instruments sufficiently insensitive to vibrations, for instance during transportation? (This applies particularly to use in measuring vehicles.)

- In the case of measuring instruments operating unsupervised, can outside manipulation be ruled out?

- In the event of measuring instruments breaking down, are spare parts or replacement instruments available at short notice to reduce interruptions?

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These points of infrastructure shall be taken into account when selecting the measurement techniques. 3.5 Data recording and documentation of the measured values All raw data required for the evaluation and traceability of the measurements shall be documented and stored. Before the measurements begin, suitable measurement report sheets and, for laboratory evaluations, sample record forms shall be prepared. The way in which the measurement data is to be recorded shall be described in the measurement plan. Wherever possible, the data should be recorded using electronic data processing facilities. The main factor is to achieve guaranteed and traceable data storage. The storage periods shall be stipulated. The measurement data shall be validated by an independent internal control body. The validated measurement data shall be identified as such and stored in such a way that they can only be amended using control codes. Details relating to any calibrations carried out as well as servicing work, instrument inspections, any malfunctions, etc. shall likewise be documented. Furthermore, the data evaluation techniques and the algorithms of statistical methods shall be documented and stored in such a way that the evaluation can be retraced at any time. 4 Measurement strategy When using measurements to investigate air pollution, the "air pollution object" measured generally has both a temporal and a spatial structure. The measurement strategy to be stipulated should be a realistic reflection of the temporal and spatial conditions occurring on the object measured during the measurement period within the measurement area. The temporal and spatial distribution of the measurements to be carried out, i.e. the measurement strategy, determine the quality or "representativeness" of this reflection. This means that the representative nature of an investigation of the air quality is not an absolute, but is a measure of the quality of the reflection, by the temporal/spatial random sample collected, of the conditions which have occurred on the "air pollution object" measured. This is also greatly influenced by the measurement outlay. Continuous measurements can be carried out, for example, to achieve a nearly uninterrupted reflection of the temporal structures of the air pollution investigated at the measurement locations. This means that the investigation will be highly representative in terms of time. In contrast, complete recording of the spatial distribution of the types of air pollution under consideration within a large measurement area is nearly impossible. Investigations of air pollution using measurements in large measurement areas will therefore be of the random sample type, at least in terms of area. The representativeness of the results of random sample investigations is generally limited and may be described by the survey-related proportion of the uncertainty of the result. When planning the measurements, the question is raised as to how these sample-related uncertainties in the investigation of air pollution can be controlled. The temporal and spatial density of the measurements and the existing temporal and spatial structures of the object measured are all deciding factors. For this reason, the

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spatial arrangement of the measuring points, the temporal distribution of sampling, the duration of individual measurements and the duration of the measurement program shall be stipulated in detail. On the one hand, it will then be possible for the timing of the measurement program to range from many time periods up to continuous registration of the measurands. However, this is only possible for some selected types of air pollution and, for reasons of outlay, usually only at comparatively few measurement locations, consequently with little spatial resolution. On the other hand, it will generally only be possible to achieve high spatial resolution at the cost of less temporal resolution. Between these two extremes, stipulations will have to be made which result from the task description and the available means. Air quality measurements will generally only provide random samples of the population. The reliability with which an investigation object can be characterized based on a random sample investigation depends on how well it is represented, i.e. reflected, by the random samples. An important task of planning the measurements therefore consists in organizing the investigations in such a way that the random samples collected are representative of the investigation object, and that it will be possible to assess the effects in question, if necessary by comparison with relevant assessment standards. The measurands must be suitable to determine the air quality characteristics required to achieve the objective. 4.1 Measurement locations Random selection of measurement locations A simple and reliable method of carrying out a random spatial selection consists in arranging the measurement locations in a square grid. This ensures that the measurement locations are independent of the basic infrastructure patterns within the measurement area, provided that these do not exhibit the same regularity as the measurement grid selected, and this can easily be checked. Measurement locations stipulated in this way form a representative random sample of the points covered by the measurement area. The grid width selected will expediently limit the achievable spatial resolution of the measurement grid produced. Thus, with a measurement grid having a grid width of 1 km, it is not possible to carry out systematic recording of spatial structures of the air quality characteristics investigated if they have an extent of less than 1 km; if appropriate, shorter distances between the measurement locations should be selected. Stratification of measurement locations The population of possible measurement locations within the area to be investigated is divided into similarity strata. The elements of each stratum have common characteristics which differentiate them from the elements of the other strata. An example of a suitable stratification is similarity with regard to the structures of use. Targeted selection of measurement locations Once conclusive and traceable data has been obtained, from which the anticipated spatial structures of the air quality characteristics investigated within the measurement area can be derived, a targeted selection of measurement locations can be made, for example at the location where the highest values of stipulated air quality characteristics are expected. Documents prepared in a traceable manner shall be kept to demonstrate how the selection of the measurement location was made.

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4.2 Measurement times Continuous recording Continuous recording of air quality characteristics is absolutely essential if information is required concerning temporarily elevated concentration values, such as is the case in warning systems. In extended measuring grids, this type of recording may prove to be expedient for other reasons, for example reducing the personnel required by having unsupervised operation of automatic analyzers or collectors. Deposit values are usually determined on the basis of continuous recording. If this type of recording is not necessary for technical reasons, preference should be given to one of the following selection procedures. Random selection of measuring times An equally distributed random selection of the measuring times, i.e. the starting times for sampling, from a given measurement period allows representative random samples to be chosen from the temporal distribution of the air quality characteristics investigated, irrespective of whether these are half-hourly, hourly or daily mean values. A precondition, however, is that the individual measurements within the random sample are independent of one another in a statistical sense. This can be achieved, for example, by collecting no more than one sample in any sampling period of up to 8 hours per day. With a sampling period of 24 hours, this can be achieved by not collecting samples on consecutive days. There are relevant regulations which give stipulations relating to sampling frequency for ambient air quality measurements. Stratification of measuring times Air quality characteristics often have typical time dependencies, for example daily cycles, weekly cycles or annual cycles. Conclusive and verifiable information on such temporal regularities can be utilized to limit the time requirement for the measurements and thus to make them more cost-effective. For instance, if the population to be investigated covers a temporal distribution over one year, information on the annual cycle can be utilized to determine annual characteristic values by extrapolation from shorter measurement periods, provided that the error bands associated with this type of extrapolation are acceptable. If dependencies of the air quality characteristics in question relating to the time of day result in elevated values during specific hours of the day, sampling carried out exclusively during these times will lead to overestimates of the characteristic values in relation to the whole day. If such overestimates can be tolerated, it is acceptable to restrict the measuring times to these particular hours of the day. Knowing the times of the day when the maximum air pollution impact occurs may also be useful for specific determination of the maximum values of the air pollution impact. In this way, if guide values are not exceeded, for example, it can be deduced with a high degree of certainty that the values at the measurement location have not been exceeded, even under unfavourable conditions. Targeted selection of measuring times If the proportions from a known source in the concentrations of specified air pollutants are to be recorded at a few specifically selected measurement locations, it

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is advisable likewise to target the selection of the measuring times, for example as a function of the emission characteristics of the source and the wind direction. It is especially advisable to make a targeted selection of measuring times if the measurements relate to effects which can be predicted to occur at specific times. This is frequently the case when investigating complaints. For instance, if the proportion of air pollution from a specific source at a given location is to be investigated, measuring times should be selected, on the one hand, at which an impact on the measurement location is anticipated owing to the activity of the source and the prevailing wind direction and, on the other hand, measuring times at which an impact due to the identified source can be ruled out. By comparing the results of the two categories, the contribution from the source in question at the measurement location can be estimated. In this case, the determination and consideration of the wind direction is thus helpful in selecting the measuring times. 4.3 Sampling period The sampling period depends on the assessment standard and the measurement procedure. For discontinuous measurements, it is usually between half an hour and 72 hours. Longer sampling times are also permissible if the assessment standard and the measurement procedure make allowance for this. 4.4 Duration of the measurement program The duration of the measurement program is to be specified in the measurement plan. In many cases, the duration of a measurement program can be deduced from the air quality characteristics in question. If, for example, annual characteristic values, such as the annual mean value or the 98-percentile, are to be determined, the measurement period should always cover 12 months. Deviations from this period are permissible in exceptional circumstances.

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If information is available concerning seasonal differences in the impact caused by the types of air pollutants in question, this information can be used for some task descriptions to arrange for the measurements to be taken only in the six-month period with the higher air pollution impact. Shortening the measurement period to 6 months is also acceptable if the air pollutant investigated has not been shown to have an annual cycle. The characteristic values derived for a six-month period are then used as estimated values for the annual characteristic values required. If the investigation relates, for example, to the frequency with which the ozone concentrations at a measurement location exceed the threshold value of 180 μg/m3, the measurements can be limited to the summer half-year since such concentrations are not experienced in the winter half-year. For measurements taken for orientation purposes, the measurement period may be reduced down to one month, provided that extrapolations known to be reliable can be carried out to estimate the annual characteristic values required. 4.5 Supplementary measurements It will often be necessary to carry out supplementary measurements to achieve the measurement target. These may include meteorological parameters if such information cannot be acquired from other sources. Other important parameters may also be details of traffic structure, such as type of vehicle, vehicle density or traffic. 5 Evaluation The rules of calculus used when evaluating the measurement data are generally required, - to obtain measured values from the measured signals, - to determine the air quality characteristics in question from the measured values, and - to estimate measurement uncertainties. More thorough statistical evaluations, e.g. for causal analysis or the planning of preventive measures, can be based on the above. 5.1 Producing measured values In order to ensure that the measurement process is reproducible, the analytical functions used, their parameters and the associated standard deviations and covariances must be documented and included in the measurement report. 5.2 Evaluation algorithms Mathematical algorithms are usually needed to determine the air quality characteristics required from the measured values. To ensure that the evaluations are reproducible, the evaluation algorithms used must be documented and included in the measurement report in a reproducible form. It is also advisable to refer to standardized evaluation procedures wherever possible. Detection limit For the purpose of the evaluation, stipulations shall be made as to how measured values below the detection limit are to be treated. These measured values can be taken into account, for example, using half the value of the detection limit.

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Measurement gaps The proportion of measurement gaps shall be specified and reasons given in the evaluation. It may be necessary to agree a maximum permissible proportion of measurement gaps. If gaps in the measurement data can be filled by calculation, the calculation method used shall be specified. The substituted measured values shall be identified as such.

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Outliers The treatment of outliers shall be specified and reasons given. The measured values determined as outliers shall be identified as such. 5.3 Measurement uncertainty During planning the measurements stipulations must also be made stating how the measurement uncertainty in the data collected is to be quantified and documented. This complies with the requirement of producing data of a known quality. The measurement uncertainty inherent in the measurement process can be characterized by specifying a standard deviation or variance in accordance with the recommendations of the international publication "Guide to the expression of uncertainty in measurement". In the simplest case, the model function used will be the analytical function. Using the methods of uncertainty propagation described in the international guideline, an equation can be derived for the variance of the measured values inherent in the measurement process. To do so, the variances and possibly also the covariances of the parameters of the analytical function describing the influencing factors must be known. The temporal and spatial structures of the measured object have no influence on the measurement uncertainty since they have to be assigned to the measured object and are thus part of the investigation. If it is impossible to specify a suitable model function which realistically describes the measurement process taking the dominant influencing factors into account, the precision and accuracy of the measured values can be quantified in accordance with the International Standard ISO 5725. Departing from the concept of the international guideline, the ISO 5725 series of standards does specify the precision of a measured value, but not its trueness as a variance or standard deviation; this is given as a bias. 5.4 Uncertainty of the result It should be examined separately during planning the measurements whether the uncertainty of the results (air quality characteristics) is to be determined in addition to the measurement uncertainty. It may be necessary to stipulate what procedure is to be applied and what additional measurement or calculation outlay this will entail. The uncertainty of the results (air quality characteristics) of an investigation of air quality based on random samples will be influenced not only by the measurement techniques used, but also by the selection of measuring times and measurement locations, i.e. by the measurement strategy selected. The question of how the measurement strategy will influence the uncertainty of the result is raised whenever conclusions are to be drawn from a limited quantity of air quality measurement data collected to give the frequency distribution (population) of the states of the measured object which occurred during the measurement period and within the measurement area. The air quality characteristics to be specified as results, such as mean value or 98-percentile are functions of the measurement data collected as random samples and as such are estimates of the corresponding characteristic values of the frequency distribution investigated which are subject to statistical uncertainties. Additional measurement and calculation outlay is generally required to examine the influence of a selected measurement strategy on the uncertainty of derived air quality characteristics, and planning this outlay requires specific knowledge of statistical investigation planning. It is therefore advisable, wherever possible, to use investigation examples and to apply these to investigations using the same measurement strategy if necessary. However, such cases must assume that the

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measurement uncertainty inherent in the measurement techniques is known. If it is only a case of ensuring that the influence of the measurement strategy on the air quality characteristics determined is comparable, a requirement for equal temporal and spatial density of the survey to be carried out is sufficient.

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6 Quality assurance The measurement plan should contain quality assurance (QA) statements. The measurement plan should clearly describe the type and scope of the QA measures to be applied. In particular, the details should include the calibration tests and comparison measurements to be carried out. The relevant reference standards or reference procedures shall be specified. If appropriate descriptions are available elsewhere, for example in the quality manual of the measurement institute, reference can be made to such documents. The details given must be sufficient to enable the intended QA measures to be verified as corresponding to the agreements or requirements. 7 Reports It is important to stipulate during the planning stage how the measurements to be carried out are to be evaluated, documented and stored. If requested by the client, an agreement should be reached concerning the type and scope of reports. The measurement report should as a minimum contain details of the following points: - Task description - Measurement methods - Measurement strategy - Results - Measurement uncertainties.

Planning of ambient air quality measurements – Rules for planning

investigations of traffic related air pollutants in key pollution areas

Content 1 Introduction 2 Problem analysis 2.1 General 2.2 Classification of the objective 2.3 Analysis of background information 2.4 Use and assessment of the measurement results 3 Organization 3.1 Project management 3.2 Personnel planning 3.3 Scheduling 3.4 Subcontracting 4 Measurement techniques 4.1 Typical measurement and sampling methods 4.2 Determining the measurement uncertainty of non-standardized measurement methods 5 Measurement strategy 5.1 General planning sequence 5.2 Preliminary measurements 5.3 Monitoring measurements

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6 Evaluation 6.1 Production of measured values 6.2 Evaluation algorithms 6.3 Measurement uncertainty 6.4 Uncertainty of the result 7 Quality assurance 8 Reporting

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1 Introduction Air pollution measurements are carried out to answer specific questions regarding specified air quality characteristics in a given area or at specified locations. A leading role is generally played by questions as to the effect of air pollutants on protected objects. The object of measurement planning is to analyze submitted objectives and from this to derive requirements of the organization, the measurement method, the measurement strategy, the assessment, the quality assurance and reporting. The report details the requirements with respect to studying traffic-related air pollution at key points where pollution occurs. The considerations reproduce fundamental knowledge to be taken into account in the planning of traffic-related studies. This is intended to enable planning of air pollution measurements in such a manner that any question asked can be answered with sufficient meaningfulness and with reasonable expenditure. This is intended to result in the fact that the measurement results obtained can be assessed with respect to their representative nature and measurement uncertainty. Traffic-related air pollutants play an important role in urban areas in particular in the vicinity of very busy roads. Vehicle occupants as well as passers by and residents are exposed to these air pollutants. To answer the question as to whether such air pollutants can lead to harmful effects on humans, not only is the concentration of the air pollutant of importance, but also the residence time of humans in the vicinity of the road traffic. When possible routes of pollution for residents are being studied, in addition to the outdoor air, indoor air pollution may also need to be taken into account. The report is relevant to all those involved with the planning, performance or assessment of studies of traffic-related air pollution. The contents can serve clients and contractors equally as a reference base, for example for formulating specifications and articles and conditions for performing studies or air quality. For the measurement planning fundamental knowledge in the following areas is helpful: - Assessment of air pollutants and effects - Atmospheric chemistry - Methodology in the trace analysis area - Meteorology - Statistics - Quality assurance 2 Problem analysis 2.1 General In problem analysis, the investigation task shall be specified to the extent that an economical solution for the measurement method and equipment resources and for the measurement strategy can be given. For this purpose it is necessary to analyze: - what objective is to be achieved, - how much prior knowledge exists at the object to be studied, - how the results of the measurement are to be assessed or utilized. During problem analysis it can be helpful to classify the task description as a standard case for which provisions or recommendations exist to carry it out. Measurement planning in the study of traffic-related air pollutants at key pollution sites may be limited essentially to the following standard cases: - preliminary measurements - monitoring measurements If the task description should not be adequately specified, it should be made more precise in a discussion with the client.

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2.2 Classification of the objective 2.2.1 Preliminary measurements Preliminary measurements are measurements of air pollutants which, with the lowest possible use of resources and within a narrow time frame, give indications as to whether and at which measuring sites in a selected area, harmful environmental effects on humans are caused by road traffic. Therefore, preliminary measurements generally have the character of spot checks. They can be used for:

providing first indications of the level of expected concentrations of air pollutants at selected measurement sites

verifying with respect to analytical methodology the selection of measurement sites for carrying out monitoring in a selected area

verifying decisions on the necessity of monitoring. Preliminary measurements of traffic-related air pollutants are generally differentiated from monitoring measurements by a lower equipment requirement, a generally simpler and more mobile measurement method and a narrow time restriction. Preliminary measurements are therefore generally considerably less costly than monitoring measurements. Under certain circumstances, preliminary measurements can replace monitoring measurements. The results of preliminary measurements are also suitable for checking simple theoretical modelling treatments, since these are frequently burdened with relatively high uncertainties. This report does not deal with questions of modelling traffic-related air pollution and possible uses of the model. Preliminary measurements can also be used to obtain initial indications of the level of pollution at places where it is not possible to obtain a description by modelling. 2.2.2 Monitoring measurements Monitoring measurements serve to monitor compliance or exceedance of predetermined environmental assessment standards. The associated measurement resources make careful planning of such measurements necessary. Monitoring measurements are generally carried out with greater frequency and over a longer period than preliminary measurements. They are carried out at measuring sites at which there are sufficient indications of the occurrence of harmful environmental effects due to air pollution and at which humans receive not only short-term exposure. Therefore, the selection of measuring sites for monitoring measurements is of great importance. In some circumstances, carefully carried-out preliminary measurements, depending on the question, can lead to the result that the available information is sufficient for an evaluation and monitoring measurements are thus no longer necessary. 2.3 Analysis of background information Planning of measurements of traffic-related air pollution can make significant usage of the analysis of existing information on the object under study. The points below shall be taken into account in analysis of background information. a) Traffic-related air pollutants Numerous citations may be found in the specialist literature on the effects of air pollutants on humans. More detailed studies should be left open to experts. In addition, it should be noted whether the objects measured are primary or secondary air pollutants, since the latter are only formed by reactions in the atmosphere and only permit restricted conclusions to be made on the originating sources. This includes, for example, ozone, which is formed, depending on the particular meteorological conditions, by reactions

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of hydrocarbons and nitrogen oxides which shall be assigned to motor vehicle traffic as primary air pollutants. b) Selection of the measuring sites Frequently, the client will select the measuring sites. In other cases, the information below can be valuable:

Road geometry

Height and density of buildings

Building use

Traffic frequency and composition

Prevailing wind direction

Background pollution This information about the source and the local circumstances and about the meteorological conditions is also useful for assessing the results and measurements to be derived therefrom. c) Level of the expected air pollutant concentrations During analysis of the background information a check shall be made as to whether information is available on the level of the expected air pollutant concentrations from measurements or modelling. This knowledge should act in supporting the decision of the type of measurement strategy to be employed. 2.4 Use and assessment of the measurement results When studies of traffic-related air pollutants are being planned, later use of the results obtained shall also be taken into account, since differing uses may result in different requirements with regard to the quality of the results. Appropriate quality requirements shall be agreed between client and contractor when the order is placed. Topics of relevance here are: - the use of type-approved measuring instruments in a calibrated state by an accredited

test laboratory - determination of the measurement uncertainty of the measured values - determination of uncertainties of the result Specific requirements shall be agreed in individual cases. The measures which are proposed by the contractor to meet the quality requirements will also effect the resultant costs of a measurement program. This shall be taken into account when different quotes are being compared. Without a reliable statement on the measurement uncertainty, the measurement values produced are ultimately not comparable and thus cannot be assessed either. At the same time, a statement of this type is a precondition for uncertainties of the result being able to be determined.

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3 Organization 3.1 Project management The person appointed as project manager shall have the knowledge and practical experience required for planning and carrying out ambient air quality measurements. A suitably qualified deputy project manager shall also be appointed. 3.2 Personnel planning Planning of the personnel resources required to carry out the measurements shall be determined and documented. The personnel shall have relevant experience of the measurement methods used. 3.3 Scheduling The time when measurements are carried out shall be fixed and documented. In the case of measurements performed as spot checks, alternative times for measurement gaps shall be provided. 3.4 Subcontracting Subcontracts should only be awarded for precisely defined tasks. The qualification of the subcontractors to carry out the task shall be verified by provision of documented evidence. Any subcontractors participating in a measurement contract shall be specified in the measurement plan. 4 Measurement techniques 4.1 Typical measurement and sampling methods The measurement and sampling methods which are suitable for carrying out measuring tasks must be known. Many sampling methods require subsequent laboratory analysis. The typical performance characteristics of measurement and sampling methods must be evaluated. The sampling method performance characteristics must include the necessary analytical determination. A distinction is must be made between preliminary measurements and monitoring measurements. The performance characteristics achieved in specific individual cases shall be determined and documented by the user. Supplementary notes on determination of the reproducibility standard deviation for non-standardized measurement methods are contained in Section 4.2. The detection limit of the measurement method should be less than 10 % of the assessment standard. Method procedures and operating procedures shall be developed for use of the measurement methods. These procedures shall be sufficiently detailed that testing is reproducible. This includes, inter alia, data on temperature and pressure references during calibration and measurement, on the calibration methods, on the frequency and scope of the required calibrations and on determination of the measurement uncertainty. To determine the measurement uncertainty, comparison measurements with reference standards or reference measurement methods shall be carried out. Unless specified otherwise, measurements shall be related to 293 K and 101.3 kPa. When measured data are archived, a distinction shall be made between the raw data and the validated data. The validated data shall be marked as such. The validation steps shall be documented so as to be reproducible.

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During measurement planning, a check shall be made as to what extent the measurement task permits clear specification of the measurands. A fundamental distinction can be made between the use of inexpensive measurement methods for preliminary measurements and the use of standardized measurement methods with type-approved measuring instruments. These are generally recommended for monitoring measurements, even if type-approved measuring instruments usually give rise to higher costs. The last column contains notes on customary averaging periods. 4.2 Determining the measurement uncertainty of non-standardized measurement methods When non-standardized measurement methods are used, the measurement uncertainty shall also be determined in the specific case of application. For this purpose, comparison measurements between the non-standardized measurement method and a reference method shall be carried out. The comparison measurements should cover the entire concentration range to be assessed and include at least thirty pairs of values. The standard uncertainty shall be determined from the comparison measurements in accordance with the recommendations of the Guide to the Expression of Uncertainty in Measurement. In this connection, the standard deviation shall also be determined from duplicate determinations. If methods based on diffusive samplers are used, data on possible deviations from the respective reference method, for example systematic overestimation or underestimation, are absolutely necessary. Duplicate determinations are advisable to a reasonable extent. For diffusive samplers, repeatability standard deviations, derived from duplication determinations, can be found in the literature. These do not always take into account effects which become apparent in comparison measurements with standardized active measurement methods (for instance the effect of turbulence). The measurement uncertainty of diffusive samplers shall therefore be set higher. 5 Measurement strategy 5.1 General planning sequence Specification of the measurement strategy essentially involves dealing with the following points: - Specification of the measurement sites - Selection of the sampling method (continuous measurement, random sampling) - Specification of the times of analysis The measurement sites can be clearly specified as early as when the objective is defined. If this is not the case or if measurements are explicitly desired at the sites of highest pollution, preliminary measurements having a spot-check character as in Section 5.2.1 are recommended. With a low analytical expenditure, these provide useable information as to where in a selected area the highest concentrations of air pollutants may be expected. In addition, preliminary measurements can provide information on the necessity of monitoring measurements at sites selected in advance. For this purpose, continuous or intermittent measurements within time limits can be carried out. Appropriate procedures may be found in Section 5.2.2. If, on the basis of information available from preliminary measurements or prior knowledge (earlier measurements, analogies drawn with other similar measurement sites, model calculations etc.), exceedance of the reference value is expected, monitoring measurements as in Section 5.3 should be planned for.

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If the results of the preliminary measurements carried out do not permit a sufficiently reliable decision to be made as to whether the specified assessment standards are complied with or exceeded, the decision basis can be improved by continuing the preliminary measurements as specified in Section 5.2.2. 5.2 Preliminary measurements 5.2.1 Locating the sites of highest pollution If the measurement sites are not predetermined or clearly fixed as a result of prior knowledge, the sites of what is suspected to be the highest pollution shall be found. The particular road section in question shall always be assessed by a site visit. To find what is suspected to be the highest polluted measurement site in a road or a road section, initially all available information about the road or road section shall be collected. This also includes estimation of concentrations of air pollutants from dispersion modelling or from analogous situations. The possible measurement sites found in this analysis in a road section or in a road or in a larger area are considered potential measurement sites for more thorough tests. The following procedure is recommended: a) Preselection of measurement sites When the measurement sites are selected, the sites which are suspected to have the highest traffic-related air pollution have first priority. These are generally roads or road sections or intersections having a high source density (e.g. the waiting area in front of traffic lights). The measurement sites should be established in a way related to the objects to be protected. The measurement sites shall therefore be established with the consideration that humans are present there not just for short times. If the consideration of these two criteria leads to differing measurement sites, the sites at which humans spend time (for example live) should receive priority. It shall be noted that the "highest air pollution" can occur at different sites for different components. It is of great importance here whether the substances under test originate only from motor vehicle emissions or from other sources as well; whether they are emitted directly by the motor vehicles or are only formed on the transport route and whether they are inert on the transport route or are subject to possible changes. In addition, both the type of building development and the meteorological conditions occurring in the area of the measurement have important effects on where the sites of highest air pollution concentrations form. In a first approach, it can be assumed that these sites, based on the prevailing open wind direction in each case (roof top wind), are on the upwind side of highly built-up street canyons and are on the downwind side of the road in the case of low-rise low-density development, in the region of a crossroads or in open land. At least three measurement sites per key pollution point should be selected. The measurement sites shall be selected with regard to carrying out a later monitoring measurement. The dimensions of the measuring instrument, any electricity or telephone connections etc. shall be taken into account. Installation of the measurement site shall not alter the pollution situation (traffic flow etc.). b) Sampling at the measurement sites At all measurement sites thus established, preliminary measurements are carried out using the same measurement method (identical measurement uncertainty) and a test period of one month. Experience shows that diffusive samplers are very highly suitable because they lead to a highly reproducible result within a relatively short time.

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It is recommended to expose diffusive samplers for benzene and nitrogen dioxide simultaneously at all measurement sites. The measurement of these two components can be used as representative of traffic-related pollutants to find the site of highest pollution. If only the measurement site of highest pollution caused by particulate pollutants is to be found, inexpensive measurement methods, for determining soot concentration can be used, and the soot concentration is then measured as representative of particulate pollutants. The use of continuous recording measuring instruments for this task is associated with higher costs. c) Evaluation of the measurement results The averages shall be calculated for each measurement site. The measurement site having the highest monthly average is established as the measurement site of highest pollution. 5.2.2 Preliminary measurements for comparison with assessment standards If it is expected that values will fall below the assessment standard (limit value, concentration value etc.), a preliminary measurement should always be carried out if it may be assumed that the data obtained therefrom, despite a relatively high uncertainty of the result, are at a safe distance from the assessment standard. In addition, a check shall be made as to whether the parameters be formed as annual averages or as percentiles. Before measurements are started, a check shall be made as to whether a shortened measurement period or random sampling is to be used. a) Shortened measurement period (sequential method) The measurement period is at least one month. The only measuring instruments which are suitable are those which enable continuous sampling of concentrations on-site, for example diffusive samplers (weekly or monthly averages) or automatic measuring stations (half-hourly or daily averages). At the end of a shortened measurement period, a check shall be made as to whether exceedance of the assessment standard can be identified directly (for example number of exceedances). To derive the uncertainty of the result, measurement results from long-term measuring stations (populations) shall be available which are subject to comparable meteorological conditions and to which comparable emission characteristics apply (comparable scattering of the measured object). The uncertainty of the result derived can only be considered as an approximation, because the actual scattering of the measured object at the measurement site is not captured. b) Random sampling The measurement period is one year. The random samples shall be distributed over this measurement period at representative times. The random sampling can be planned on the basis of half-hourly, daily or monthly averages. Using random sampling, not only annual averages, but, with a suitable sample size, percentiles can also be determined. The uncertainty of the result can be estimated in advance of the measurements (planning) for a given sample size. The actual uncertainty of the result, however, cannot be derived until the random sample is obtained, because the actual scattering of the measured object is detected at the measurement site. There shall be clarification as to whether the results of the preliminary measurements as in Section 5.2.1 (for finding the site of the highest pollution) may possibly be useful for further decision-making observations.

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If the one-month series of measurements (as in Section 5.2.1) can lead to a sufficiently precise statement of compliance with the assessment standard (shortened measurement period), the measurements do not need to be continued. To check this question, the uncertainty of the result shall be determined for this one-month series of measurements. If the same measurement method is used for the continuing measurements (for example benzene diffusive sampler) as in the measurements according to Section 5.2.1, the measurements already available can be taken into account in the evaluation. 5.3 Monitoring measurements If preliminary measurements as in Section 5.2.2 over a period of twelve months are already available which result in reliable exceedance of the reference value taking into account the uncertainty of the measurement method used, these can be assessed as monitoring measurements. The measurement period for monitoring measurements is generally at least one year. Grounds for shortening the measurement period to six months shall be given in detail. The measured values which were measured within the measurement period at one measurement site are used to calculate the statistical characteristics (annual average, percentile) needed for comparison with the assessment standard. In addition, the agreed data on measurement and uncertainty of the result shall be determined and documented. 6 Evaluation 6.1 Production of measured values To ensure that the measuring process is reproducible, the analytical functions used, their parameters and the associated standard deviations and covariances shall be documented and presented in the test report. The reference values for temperature and pressure used to convert the measured values to reference conditions shall be stated. 6.2 Evaluation algorithms To determine the wanted air quality characteristics from the measured values, generally mathematical algorithms are needed. To ensure that the evaluations are reproducible, it is necessary to document the evaluation algorithms used. It is advisable here to refer to standardized evaluation methods as far as possible. Detection limit For the evaluation it is necessary to specify how measured values beneath the detection limit are treated. Measures of this type can be taken into account, for example, using the value of half the detection limit. Measured values which are below the detection limit shall be identified. Measurement gaps The proportion of measurement gaps shall be specified in the evaluation and justified. A maximum permissible number or the permissible period of measurement gaps shall if necessary be agreed. If gaps in the measurement data can be filled by calculation, the calculation method used shall be specified or cited. The substituted measured values shall be identified as such. Outliers The treatment of outliers shall be specified and justified. The measured values determined as outliers shall be identified as such.

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6.3 Measurement uncertainty The test plan shall specify which data shall be determined to describe the measurement uncertainty. The recommendations of the Guide to the Expression of Uncertainty in Measurement shall be heeded here. This applies not only to preliminary measurements but also to monitoring measurements. 6.4 Uncertainty of the result There shall be a specification in the measurement plan as to how uncertainty of the result is to be quantified. The uncertainty of the result is differentiated from the measurement uncertainty to be determined by an additional figure to describe the effect of a random sampling process on the overall uncertainty of a result. When, for example, diffusive samplers are used, which are used without gaps during the entire measurement period, the uncertainty of the sampling process can be set at zero. The same applies to complete determination of variation of the measured quantities with time at the measurement sites by continuous measurements. If the population at the measurement site is not determined completely (for example sampling with diffusive samplers is not without gaps, no continuous series of measurement), the variation of the measured quantity with time (scattering of the measured object) at the measurement site effects the uncertainty of the result of the characteristic calculated from the random sample. The uncertainty of the sampling process can in such cases be considerably greater than the measurement uncertainty. 7 Quality assurance The measurement plan shall contain statements on quality assurance (QA). The type and scope of the planned QA measures shall be clearly and unambiguously described in the measurement plan. The calibrations and comparison measurements to be carried out shall be mentioned here in particular. The reference standards or reference methods intended for these purposes shall be specified. If appropriate descriptions are available at another accessible place, for example in the Quality Assurance Handbook of the Test Institute, a reference may be made to this. The specifications shall be extensive in order to be able to check whether the intended QA measures correspond to the agreements or conditions. 8 Reporting In the planning stage a specification shall be made as to in which manner the measurements to be carried out are to be evaluated, documented and archived. To the extent this is desired by the client, there shall be agreement over the type and extent of reporting. The test report shall contain at least details of the following points: - Task description - Execution of the measurements - Measurement uncertainties and uncertainties of the result - Results.

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Measurement Strategies for the Determination of Air Quality

Characteristics in the Vicinity of Stationary Emission Sources

Content

1. Introduction 2. General requirements 3. Task definition 4. Selection of measurement sites 5. Temporal distribution of measurements 6. Measurement techniques of air quality measurements 7. Determination of the results 8. Determination of the uncertainty of the results 9. Reporting 10. Quality assurance 11. Organization

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1. Introduction

The report describes rules of planning the determination of air quality characteristics in the vicinity of stationary emission sources. This may be applied if the emission sources considered are specified as individual point or plane sources or groups of such sources showing a common surrounding, where the contribution of these emission sources to the air quality characteristic of interest is relevant. Air quality characteristics considered are mean values and numbers of exceedances of different aggregations of measured values (e.g. quantiles). The present report describes two measurement strategies of performing investigations, which are specifically designed for complementary boundary conditions: • Measurement strategy A: Determination of air quality characteristics in the vicinity of the emission sources considered by measurements at a selected measurement site; the selection of the measurement site and the assessment of the spatial transfer (representativeness) are based on dispersion calculations • Measurement strategy B: Determination of air quality characteristics in the vicinity of the emission sources considered by measurements at least at four spatially distributed measurement sites Measurement strategy A may be applied, if background information providing usable data on the spatial structure of the air quality characteristics of interest is available from dispersion calculations. Measurement strategy B may be applied, if the spatial distribution of air quality characteristics in the area of determination shall be determined by means of continuous or discontinuous measurements and background information providing usable data on the spatial structure of the air quality characteristics of interest obtained by dispersion calculations is not available. The specified measurement strategies allow correct and comparable implementations of legal requirements in the field of environmental protection, e.g. within the context of European Directives or in legal air quality control. 2 General requirements The report describes systematic rules of determination of air quality characteristics in the vicinity of stationary emission sources. This report may be applied, if the emission sources considered are specified as individual point or plane sources or groups of such sources showing a common surrounding, where the contribution of these emission sources to the air quality characteristic of interest is relevant. Relevant contributions to an air quality characteristic are to be expected within a radius R = 50-H about the emission source with stack height H, if not otherwise specified. Corresponding regulations are laid down in administrative requirements. Air quality characteristics considered are e.g. mean values and numbers of exceedances of assessment standards. The measurement task shall include descriptions of the air quality characteristics to be determined and the protected objects to be considered as well as a description of the assessment standards to be. If the measurement task does not include specifications regarding the area and period of determination, the measurement strategy and the data quality objectives, such boundary conditions shall be specified within the measurement planning. Data quality objectives shall be specified to guarantee a determination of air quality characteristics with known quality. This leads to results of such investigations which can be compared and assessed. The data quality objectives of air quality characteristics to be determined are influenced by the uncertainties of the applied methods of determination, the

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incompleteness of the determination of temporal structures and the incompleteness of the determination of spatial structures of the air pollutants under investigation. The task of measurement planning is to draw up unambiguous and complete technical specifications of the investigations to be performed, which can be carried out by trained personnel. If necessary, different ways of realization of the measurement task shall be checked and assessed. If the measurement task requires more detailed specification, this shall be agreed with the client. Measurement planning is not necessarily performed as a linear sequence of predefined work steps, but can also be understood as a network of interrelated control systems, which may be applied repeatedly to optimize the measurement plan under the specified boundary conditions. The result of planning shall be documented in a measurement plan, which specifies the planned flow of investigations to be performed. The following items shall be dealt with: • Task definition • Selection of measurement sites • Temporal distribution of measurements • Measurement techniques • Evaluation • Determination of the uncertainty of the result • Reporting • Quality assurance • Organization 3 Task definition 3.1 Requirements The task definition to be described in the measurement plan should specify: Air quality characteristics to be determined Assessment standards to be applied Protected objects of interest Area of determination to be investigated Period of determination to be considered Data quality objectives In the measurement planning the task definition shall be analyzed and put into such concrete terms that an unambiguous technical draft of the determinations to be performed can be established. This may require agreement with the client. 3.2 Air quality characteristics and assessment standards The air pollutants to be investigated and the air quality characteristics to be determined shall be described in the measurement plan. Air quality characteristics may be for example mean values and numbers of exceedances of limit values. The measurement plan shall specify for each air quality characteristic the limit value to be applied or the relevant assessment standard. 3.3 Protected objects The protected objects of interest shall be specified for each air quality characteristic to be determined. Protected objects exposed to the influence of airborne emissions of the sources considered may be humans, eco systems, soil or material. Information on protected objects may usually be found in legal regulations for environmental protection, which include assessment standards. Protected objects taken into account in the planning of measurement shall be specified in the measurement plan. 3.4 Area of determination The area where determinations shall be performed, the so-called area of determination, has to be unambiguously specified and described in the measurement plan (e.g. by graphical representation). This may be based on one of the following procedures:

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a) Specification of the area of determination by reference to an administrative regulation to be applied. This procedure requires that the specification of the area of determination is laid down in an administrative regulation to be applied.

b) Specification of the area of determination by assigning circular areas of radius R = 50-H to each source with stack height H, the sum of these areas gives the area of determination. Minor background information on the expected spatial structure of the air quality characteristics of interest or background information of minor quality is needed for this procedure.

c) Specification of the area of determination by dispersion calculations. For all air quality characteristics of interest that area is determined, where the total contribution of the sources considered is relevant. This procedure requires that background information on the expected spatial structure of the air quality characteristics of interest extensive and of good quality.

d) Specification of the area of determination by other procedures. The procedure of specification of the area of determination shall be comprehensively described in the measurement plan.

3.5 Period of determination The period of determination of the investigations to be performed shall be specified in the measurement plan. The period of determination is usually defined in the legal regulations for environmental protection to be applied. If the assessment standards to be applied are limit values of EU Directives, the period of determination is usually one year. The period of determination may be shortened if a representative assessment of the whole year is still possible. The reasons for shortening the period of determination shall be given in the measurement plan. 3.6 Data quality objectives 3.6.1 General If the uncertainty of air quality characteristics to be determined shall fulfill specified requirements, these requirements shall be presented as data quality objectives in the measurement plan. Data quality objectives have influence on the expense of determinations to be performed and therefore on the uncertainty of the results. The uncertainty of the results and accordingly the confidence in the air quality characteristics to be determined is influenced by • the measurement and evaluation methods • the temporal density of measurements • the spatial density of measurements 3.6.2 Requirements on the quality of measured values Requirements on the quality of measured values may be: • Determination of the standard uncertainty of the measured values • Check whether the expanded uncertainty of the measured values on a 95 %

confidence level is smaller than a specified percentage proportion of the assessment standard to be applied

Usually, the determination of the standard uncertainty of the individual values shall be demanded, since that forms the basis for the determination of the uncertainty of the result and the expanded uncertainty. Standard uncertainties shall usually be quantified as absolute values in the unit of the corresponding measured value. 3.6.3 Requirements on the completeness of the temporal registration Requirements on the temporal registration (availability) of air quality characteristics to be determined may be specified by the required temporal coverage of the period of determination or by limitation of the standard uncertainty of the air quality characteristics caused by the random sampling.

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Completeness of the temporal coverage: Continuous measurements may usually realize a temporal coverage of the period of determination of up to 95 %. In case of random sampling, the minimum number of samples depends on the required temporal coverage of the period of determination. The temporal distribution of the measured values over the period of determination shall be performed in such a way that the registered data set is representative of the temporal distribution of the air quality characteristics within the period of determination. This is usually fulfilled, if the measurement times are equally distributed over the whole period of determination. Limitation of the standard uncertainty caused by random sampling: A requirement on the completeness of the temporal registration may be derived from requirements for the maximum value of the standard uncertainty of an annual characteristic (mean value, number of exceedances) caused by random sampling. This will usually be based on experience with values determined in similar investigations. 3.6.4 Requirements on the selection of measurement sites Requirements on the selection of measurement sites may be specified as follows: a) A measurement site should be located where the highest value of the annual mean of the background pollution is expected. Such requirement makes sense and is appropriate if the following usable background information is available: • the spatial distribution of the background pollution caused by the air quality characteristic of interest in the area of determination • the emissions of the stationary sources considered for the air pollutants of interest • the meteorological exchange conditions in the area of determination b) A measurement site should be located where the highest value of the annual mean of the additional pollution is expected. Such requirement makes sense and is appropriate if the following usable background information is available: • the emissions of the stationary sources considered for the air pollutants of interest • the meteorological exchange conditions in the area of determination c) A measurement site should be located where the annual mean of the additional pollution exceeds a percentage value p of assessment standard. d) At least four measurement sites shall be located in a grid. Such requirement makes sense and is appropriate if the required background information to perform dispersion calculations is not available or can not be used. This requirement includes the specification of the desired distance between measurement sites. If necessary, a number of measurement sites larger than four shall be specified. 3.6.5 Additional requirements For application of measurement strategy A, additional requirements may be specified in the measurement plan, for example requirements on the type of dispersion model to be applied, the provision of emission data, the provision of meteorological data. 4 Selection of measurement sites 4.1 General The method to be applied for the selection of measurement sites shall be described in the measurement plan. It shall be guaranteed that data quality objectives related to the spatial registration of the measurands to be investigated are fulfilled. In the framework of measurement planning, the work and test steps to be taken shall be identified and temporally specified for each investigation program (project planning). The work steps are primarily defined by the measurement strategy to be applied. Test steps usually serve to control the determination process. Such decisions can be used for example for limitation of the determination effort, if no more essential information is expected, or for increasing the determination effort, if the amount of information needed is larger than expected. When a specified level of information is reached, a test step can allow modifications or breaking-off

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the investigations dependent on intermediate results. Such a test step allows for example a check at the beginning of the investigations whether the expected additional pollution caused by the sources considered reaches a level which is detectable by measurements. If this is not the case, the planned measurements may only increase the knowledge on the background pollution. Measurement strategy A Measurement strategy A may be applied if usable background information on the spatial structure of the air quality characteristics of interest is available from dispersion calculations. The results of dispersion calculations from several calendar years may be used to assess the quality of such a selection of measurement sites. This requires information on the emissions of the sources considered and the meteorological conditions in the calendar years considered. The number of calendar years considered shall be specified in the measurement plan. An assessment period of five years is recommended following the first Daughter Directive of the EU. Measurement strategy B Measurement strategy B may be applied for the determination of the spatial distribution of air quality characteristics in the area of determination by means of timely stratified or randomly distributed (discontinuous) measurements, if usable background information on the spatial structure of air quality characteristics of interest is not available from dispersion calculations. Measurement strategy B is solely based on measurements of air pollutants at spatially distributed measurement sites in the area of determination to determine the spatial structure of the air quality characteristics of interest. The spatial resolution of such investigations is defined by the spatial distribution of the measurement sites in the area of determination. 4.2.1 Provision of annual mean values of the background pollution Application of alternative a) of Section 3.6.4 requires the provision of estimates of the annual mean values of the background pollution for the selection of measurement sites. If emission sources (plants) already exist, the three or four closest regional stationary measurement sites shall be considered for the determination of the background pollution. These stationary measurement sites should be located outside the area of determination. Furthermore, they should not be located in the range of influence of similar sources. The provided annual mean values of the background pollution shall be representative of several (five) calendar years. The determination of the background pollution and the assessment of its representativeness shall be described in the measurement plan.

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4.2.2 Calculation of the background pollution 4.2.2.1 General The selection of measurement sites is based on a separate determination of the locations of the maximum additional pollution caused by the emission sources of interest in the area of determination for the specified calendar years. The locations of maximum additional pollution establish the basis for the selection of measurement sites by application of measurement strategy A. 4.2.2.2 Provision of a dispersion model The dispersion model is applied for the selection of measurement sites and for the assessment of measurement sites. Dispersion models fulfilling the requirements may be applied. The dispersion models applied for the selection and assessment of measurement sites shall be specified in the measurement plan. 4.2.2.3 Provision of emission data Emission data of the considered sources expected in the period of determination shall be provided for the dispersion calculations. Usually, this includes the following specifications: • Identification number of the source • Location of the source (coordinates) • Emission source height • Area of the emission source plane • Waste gas temperature • Emitted component • Volume flow • Emission mass flow The requirements on the input data shall be taken from the handbook of the dispersion model applied. In the measurement plan the following shall be specified: • Emission data required • Provision of the emission data required 4.2.2.4 Provision of meteorological data The application of the dispersion model selected requires meteorological data representative of the dispersion conditions in the area of determination. The meteorological data required shall be provided as follows: a) separately for the previous calendar years, which are used for the selection of measurement sites b) for the period of determination to assess the measurement site Dispersion models require as meteorological input data a time series of the influence quantities wind direction, wind velocity and stability, representative of the area of determination, or a frequency distribution of the influence quantities wind direction, wind velocity and stability or a frequency distribution of the influence quantities wind direction, wind velocity and stability. It shall be documented in the measurement plan which meteorological data were used and how the meteorological data required were determined 4.2.3 Calculation of the total pollution If estimates of the total pollution are required for the selection of measurement sites, these values shall be calculated as follows by means of the background and additional pollution for each calendar year considered. The annual mean value of the total pollution G(x) at site x is calculated as the sum of the annual mean value of the background pollution V(x) and the calculated annual mean value of the addition pollution Z(x) according to Equation (I): G(x)=V(x)+Z(x) (1)

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The number of exceedances NG(B) of the assessment standard B caused by the background pollution at site x shall be estimated for the case Z « V « B considered in this report according to Equation (2): NG(B)=NV(B-Z(X)) (2) The term NV(B-Z(x)) describes the number of exceedances of threshold value (B-Z(x)) in the background pollution. The locations of the maximum values of the total pollution shall be separately specified for the calendar years considered. Deviations from these procedures shall be comprehensively described in the measurement plan. 4.2.4 Selection of the measurement site based on the maximum additional pollution The measurement site shall be selected from the set of those sites, where the mean value of the additional pollution was calculated as a maximum for the calendar years considered. If an unambiguous accumulation of sites calculated can not be identified, an additional measurement site shall be specified, if necessary. The spatial distribution of the calculated sites of highest additional pollution allows an assessment of the uncertainty caused by the selection of the measurement sites. 4.2.5 Selection of the measurement site based on the maximum total pollution The measurement site shall be selected from the set of those sites, where the mean value of the total pollution was calculated as a maximum for the calendar years considered. If an unambiguous accumulation of sites calculated can not be identified, an additional measurement site shall be specified, if necessary. The spatial distribution of the calculated sites of highest total pollution allows an assessment of the uncertainty caused by the selection of the measurement sites. 4.3 Measurement strategy B Application of measurement strategy B for the determination of air quality characteristics in the specified area of determination requires a selection of the measurement sites in such a way that the data quality objective related to the spatial registration is fulfilled. At least four measurement sites shall be specified. If the maximum distance between neighbouring measurement sites is given, the following selection procedures may be applied: a) Random selection: Location of the measurement sites in a quadratic grid of grid width x outside the factory site. The value x describes the spatial resolution of measurements specified by the data quality objective. The value x should be 250 m or a multiple of 250 m. b) Stratified selection of measurement sites: The distance from a central source location is used as a stratification characteristic. Stratum n of measurement sites is located at distance n x in radial direction from the specified source location. The distance between measurement sites in stratum n is smaller or equal to n x. The number of stratums is limited by the radius of the area of determination, i.e. nx < 50H. In order to implement the requirement of a maximum difference of the air quality characteristic considered at the measurement site or at neighbouring measurement sites as a data quality objective of the spatial registration, dispersion calculations shall be used, which allow the determination of the expected gradients in the area of determination. 5 Temporal distribution of measurements 5.1 Requirements The measurement plan shall specify the temporal distribution of measurements in the period of determination. It shall be guaranteed that • the data quality objective related to the temporal registration of measurands to be investigated is fulfilled

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• the temporal representativeness of the measurements is achieved The latter is guaranteed if the measurement times are equally distributed over the whole period of determination. 5.2 Continuous measurements The temporal distribution of the air quality characteristics of interest shall be determined by continuous measurements, if the required coverage is not achieved by random measurements. This requires that • an appropriate automated measuring system is available • an automated measuring system can be used at the measurement sites 5.3 Random measurements The temporal distribution of the air quality characteristics of interest can be determined by random measurements, if the data quality objective for the temporal registration is met. 6 Measurement techniques of air quality measurements 6.1 Requirements The measurement techniques applied for the measurement of air pollutants of interest shall be selected and applied such that the specified data quality objectives are fulfilled. Appropriate measures shall be planned to verify that the data quality objectives are fulfilled under the conditions of the determinations to be performed. In any case this includes the determination of the uncertainty of the measured values. 6.2 Measurands and measuring systems The sampling and measurement techniques to be applied shall be unambiguously specified and documented in the measurement plan for each air pollutant to be investigated. If suitability-tested measuring systems exist, these shall be used. The measured values to be determined shall be characterized with respect to their reference time period. The mode of temporal Registration shall be described. The detection limit which can be practically realized shall be given for information. The available measurement techniques are described in the VDI/DIN manual on air pollution prevention. 6.3 Determination of measurement uncertainty It shall be specified which control measures are to be performed to determine measurement uncertainties. The simplest control measures are: • Check of the calibration status of the measuring system by repeated application of the measuring system to check standards (test gases) with known uncertainty under measuring conditions • Check of the calibration status of the measuring system by participation in round robin tests • Repeated parallel determination with two measuring systems (if systematic deviations are not expected) Parallel determinations are suitable control measures, if the measured values determined do not show any common systematic deviation. This assumption is often fulfilled in the comparison of two identical measuring systems provided these systems are used independently and are calibrated with different reference materials. Round robin tests are suitable control measures, if the uncertainties of the reference values are known. This can usually be achieved by statistical evaluation (mean value, median) of the measured values of all participants or of a selected sub-set. 6.4 Data acquisition

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It has to be specified, which raw data shall be determined and how these raw data shall be determined and archived. Furthermore, it has to be specified, which control data used for the determination of measurement uncertainty shall be determined and how these control data shall be determined and archived. 7 Determination of the result The measurement plan shall specify the arithmetic rules to be used for the evaluation of the measurements. This can be realized by specification of the arithmetic rules or by reference to this report. Evaluations shall be individually performed for each measurement site. The handling of measured values below the detection limit of the measured system applied shall be specified. In the following, suitable calculation procedures for application of measurement strategy A and B are described. If different calculation procedures are applied, this shall be documented in the measurement plan. 8 Determination of the uncertainty of the result In order to check that requirements on the data quality are met, the contributions to the uncertainty of the result shall be determined. These uncertainty contributions are caused by: • the measuring system applied • the temporal registration by measurements • the spatial registration by measurements The uncertainty of an air quality characteristic L is described in accordance with the recommendations of the Guide to the Expression of Uncertainty in Measurement by the (combined) standard uncertainty u(L) given by Equation (3): u2(L) = u2

M(L) + u2T(L) + u2

SP(L) (3) where u2

M(L) is the variance contribution caused by the measurement techniques u2

T(L) is the variance contribution caused by incomplete temporal coverage (measure of the temporal representativeness of air quality characteristic L) u2

SP(L) is the variance contribution caused by incomplete spatial coverage of the spatial structures investigated (measure of the spatial representativeness of the air quality characteristic L) Deviating procedures for the determination of data quality characteristics shall be separately documented in the measurement plan. 9 Reporting Requirements and agreements on type and scope of the reporting on the results of the investigations to be performed shall be specified in the measurement plan. An outline of the report(s) to be established may be agreed. 10 Quality assurance The measurement plan shall contain requirements and agreements on type and scope of the quality assurance measures in the framework of the investigations to be performed. A quality controlled performance of the measurement program or an acceptance check of the results may be agreed. 11 Organization 11.1 Project management

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For the project management a person shall be appointed who has the knowledge and practical experience required for planning and carrying out ambient air quality measurements. A suitably qualified deputy project manager shall also be appointed. 11.2 Personnel planning The personnel resources required to carry out the measurements shall be planned taking into account the measurement task. The personnel shall have relevant experience of the measurement methods used. Technicians and assistants should have gained knowledge by practical application in the filed of ambient air quality measurements. Technical education and knowledge in electronics and PC applications are advantageous. 11.3 Scheduling The temporal performing of measurements shall be planned and organized taking into account the measurement strategy and the measurement method. The scheduling shall be documented. In the case of random measurements, alternative times for measurement gaps shall be provided.

Handling of Measurement Uncertainty

Content

1. Introduction 2. Description, specification and summary of the standard uncertainties

3. Combined standard uncertainties 4. Concentration dependency of the measurement uncertainty 5. Extend of the uncertainty 6. Result documentation and specification

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1. Introduction

In accordance to the requirements of DIN EN ISO 17025 testing laboratories must execute procedures for estimation of the measurement uncertainties. This means that for validated and tested investigation procedures the uncertainties contributions must be specified for containing the essential error contributions. The precision of the uncertainty estimation should be complied with the task requirements and the selected procedure should be clear and practical. Regarding the environmental analysis, a measurement uncertainty will be actually understand as procedure uncertainty or result uncertainty, so that measurement uncertainty takes in considerations the previous steps of the sampling and the sampling, where this is possible and meaningful. This requirement does not apply for qualitative and half-qualitative procedures. Standard procedures with specifications about measurement uncertainty need no further approach of the error, if this specification will be clearly checked by the investigation center. The principle approach according to DIN ENV 13005 will be described. Basically priority will be given to the concept of the extended measurement uncertainty. Simplifying, it is first sufficient to use the present knowledge about the investigation method. Data resulted within the routine quality management of uncertainty estimation will be used. The main error contributions will be captured and discussed about. A strict mathematical method it is not absolute necessary.

2. Description, specification and summary of the standard uncertainty

The approached investigation procedure is to be referred and every error step (standard uncertainty) are to be described, so that the relevant uncertainty contributions can be recognized and correlated one to another, for example by means of the cause/effect-diagram: For the error estimations can the following generally be used:

- Technical measurable uncertainty contributions (Tip A) from the precision-repetition studies of the validation investigations, from the control-chart systems (standard deviations of the average values ranges) or calibration functions,

- another estimated contributions (tip B) (scientifically experience from previous or similar tests and literature, tolerance from the calibration and instrument certificates, results of the appropriate round robin test, another determining factor (for example p,T, V)).

Following the scope, continuously part-steps are centralized to „uncertainty module or uncertainty budgets―. There are many standard uncertainties integrated and it‘s not absolute necessary each of them to be evaluated. Such uncertainties modules are often qualified as type error from the card chard of the routine quality assurance A (here: standard deviation):

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The average value KK of the content of an independent control solution reflects for example the error contributions of the standard solutions, work calibration and measurement. Having a KK-range, the systematically error of the instruments variation can be included. If the ranges of the control cards are established with real samples, the matrix effects will be additionally taken into account. The determination of an appropriate reference material is very adequate for monitoring of the entire procedure where the sample preparation and if necessary, the matrix interconnection are included. The total procedure uncertainty can be evaluated in one step from one inserted KK average value.

3. Combined standard uncertainties

By calculating, the standard uncertainties of each regarded i step it can be centralised respectively combined also to ―uncertainty modules‖ uy. The law of the error propagation will be always applied related to a functional connection. This means for a combined measurement uncertainty uy:

ux

fu i

N

iy

i

2

1

2

2

bei y = f (x1, x2, x3, x4…xi)

The principal for a variation addition is derived for a simple, linear correlation:

uu iy

2

If a calculated partial result is functional composed as product or quotient of many individual factors, than the relative variations will be added:

uu relirely

2,,

4. Concentration dependency of the measurement uncertainty

Often in the environmental analyse big concentration sites are approached, so that it can‘t come up with an existence of variation homogeneity over the entire measurement site. So it is preferable that more uncertainty evaluation will be established in the fields with decisional relevant contents. Since these are often different and task specific, it should be established at least evaluations from ex. control card systems related to concentration.

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5. Uncertainty extension

In the most cases not all the error contributions can be centralised in an uncertainty evaluation. For this reason the evaluated result uncertainty must be extended to a safety factor. Usually a 2 factor will be recommended, since afterwards a minimal 95% confidence field can be met:

U = k utot mit k = 2

6. Documentation and result specification

The last result should be given the following form, including the expanded uncertainty:

Y U (VB = 95%) or

Y Urel The process of identifying the measurement uncertainty has to be transparent documented for every step. The most important determining factors have to be named. The quantifying and the type of the calculated combination have to be documented. It will be regarded that the estimation values for the uncertainty comply with the typical task requirements (for ex. error in field of test values). All the documentation will be attached to the validation documentations. On request, the determination methods are open for the client. Specification of the extended result uncertainty will be agreed with the client. The type of the specified measurement uncertainty, that has a quality, will be continuously specified.

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Selection of Sites for Air Quality Measurements According to the Air Quality Directive 2008/50/EC and the

4th

Daughter Directive 2004/107/EC

Content

1. Assessment regimes ..................................................................................................... 66

2. Minimum number of monitoring stations required for each pollutant in a zone ....... 67

3. Recommendations for monitoring site selection ........................................................ 70

4. Macro-scale siting criteria for monitoring stations ..................................................... 73 4.1 Protection of human health ........................................................................................ 73 4.2 Protection of vegetation and natural ecosystems ....................................................... 74 4.3 Protection of human health and vegetation, Ozone ................................................... 74

5. Micro-scale siting criteria for monitoring stations ...................................................... 76 5.1 Requirements ............................................................................................................ 76 5.2 Documentation and review of site selection ............................................................... 77

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This guidance document deals with the requirements for the spatial distribution and siting of air quality monitoring stations. It is based on the requirements laid down in Annex III, Annex V and Annex IX of the Air Quality Directive (AQD) 2008/50/EC.

1. Assessment regimes

Annex V of the Air Quality Directive defines different requirements for air quality assessment

- measurement, modelling and objective estimation - , depending on the pollution level in

relation to the lower and upper assessment threshold (which are laid down in Annex II of the

Air Quality Directive and Annex II of the 4th Daughter Directive).

upper assessment threshold (UAT)

lower assessment threshold (LAT)

measurements are mandatory in all agglomerations and other zones

Measurements are mandatory, but the requirements are reduced, in all

agglomerations and other zones:

may be supplemented by other methods (models, passive/random sampling..)

objective estimation, models, random/passive sampling, etc sufficient.

Exception: pollutants for which an alert threshold has been set (SO2, NO2) must be measured in

agglomerations (minimum 1 site)

limit value

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2. Minimum number of monitoring stations required for each pollutant in a zone

The minimum number of monitoring stations for sulphur dioxide, nitrogen dioxide and oxides

of nitrogen, PM10, PM2.5, lead, benzene, and carbon monoxide per zone according to

Annex V.A.1 of the Air Quality Directive depends – besides the population of the zone – on

the pollution level in relation to the lower and upper assessment threshold.

It can, however, be assumed that in all zones in the Marmara Region the pollution exceeds

the upper assessment threshold.

This means that the following minimum number of monitoring stations applies:

Population of agglomeration or zone

(thousands)

If maximum concentrations exceed the upper assessment threshold

Pollutants except PM Sum of PM10 and PM2.5

0 - 249 1 2

250 - 499 2 3

500 - 749 2 3

750 - 999 3 4

1,000 - 1,499 4 6

1,500 - 1,999 5 7

2,000 - 2,749 6 8

2,750 - 3,749 7 10

3,750 - 4,749 8 11

4,750 - 5,999 9 13

≥6000 10 15

It has to be noted that the numbers in the above table (according to Annex V.A.1 of the Air

Quality Directive) represent the minimum requirements, which also apply for completely flat

countries like the Netherlands or Finland. In such countries, dispersion conditions are

spatially uniform (however, sea breeze effects may play a role), and the spatial distribution of

the pollution levels only depends mainly on the location of emissions.

In zones which complex topographic and climatic conditions and with spatially variable

dispersion conditions, the numbers given in Annex V.A.1 are definitely insufficient to acquire

fairly representative information about air quality in the whole zone.

A zone where the range of altitude exceeds 500 m is considered as “complex terrain”.

For the pollutants NO2, PM10, PM2.5, Benzene, and CO, in each zone at least

one urban background monitoring station

one traffic related monitoring station

are required.

The ratio between the numbers of background and traffic related stations must not exceed a

factor of 2 (i.e. the number of traffic related stations has to be between 50% and 200% of the

background stations).

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The ratio between the numbers of PM10 and PM2.5 stations must not exceed a factor of 2

(which means in practice, since the PM10 monitoring stations usually already exist, the

number of PM2.5 stations has to be at least 50% of the PM10 stations).

In addition to the background and traffic related stations, the number and location of

monitoring stations related to point sources shall depend on

the emissions,

the spatial distribution of pollution,

the exposure of population.

Definition of site types (according to the Guidance to the Exchange of Information Decision):

Background: Located such that its pollution level is not influenced significantly by any single

source or street, but rather by the integrated contribution from all sources upwind of the

station (e.g. by all traffic, combustion sources etc. upwind of the station in a city, or by all

upwind source areas (cities, industrial areas) in a rural area).

Traffic: Located such that its pollution level is determined predominantly by the emissions

from nearby traffic (roads, motorways, highways).

Industrial: Located such that its pollution level is influenced predominantly by emissions

from nearby single industrial sources or industrial areas with many sources. Industry source

is here taken in its wide meaning including sources like power generation, incinerators and

waste treatment plants and agglomeration of small facilities like Organised Industrial Zones

(OSB).

For the protection of the vegetation (SO2, NOx), in each zone (except agglomerations), at

least one monitoring station per 20,000 km² is required.

The minimum number of ozone monitoring stations according to Annex IX.A of the AQD is

given in the following table.

At least one site in each zone has to be located in exposure-relevant suburban areas. In

agglomerations, at least 50% of the sites have to be located in suburban areas.

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Population Agglomerations -

urban and suburban

areas

Non-agglomeration-

zones - urban and

suburban areas

Rural background

< 250,000 0 1 1 site per 50,000 km²

1 site per 25,000 km²

in structured terrain 250,000 – 500,000 1 2

500,000 – 1,000,000 2 2

1,000,000 – 1,500,000 3 3

1,500,000 – 2,000,000 3 4

2,000,000 – 2,750,000 4 5

2,750,000 – 3,750,000 5 6

> 3,750,000 1 additional site per 2

million inhabitants

1 additional site per 2

million inhabitants

General requirements on spatial air quality assessment

Ambient air quality shall be assessed in all zones and agglomerations in accordance with the

following criteria:

1 Ambient air quality shall be assessed at all locations except those listed in paragraph

2, in accordance with the criteria established by Sections 0 and 0 for the location of

sampling points for fixed measurement. The principles established by Sections 0 and

0 shall also apply in so far as they are relevant in identifying the specific locations in

which concentration of the relevant pollutants are established where ambient air

quality is assessed by indicative measurement or modelling.

2 Compliance with the limit values directed at the protection of human health shall not

be assessed at the following locations:

(a) any locations situated within areas where members of the public do not have

access and there is no fixed habitation;1

(b) on factory premises or at industrial installations to which all relevant provisions

concerning health and safety at work apply;

(c) on the carriageway of roads; and on the central reservations of roads except

where there is normally pedestrian access to the central reservation.

1 e.g. military premises.

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3. Recommendations for monitoring site selection

The first step for site selection is the identification of

(a) urban background areas,

(b) traffic influenced areas,

(c) industrial areas and

(d) rural areas within a zone.

Most industrial facilities in Serbia have small stack heights (< 25 m) and so the maximum

concentration is quite close (< 1.2 km) to the source. It is recommended to locate monitoring

stations for monitoring of industrial sources between industrial and residential areas, in order

to measure the immediate impact on resident population.

Industrial monitoring sites should be located downwind of the industrial sources, related to

the predominant wind direction. To identify the main wind direction or the distribution of wind

directions, data from several years should be used; the assessment of wind direction

requires special attention in areas with complex terrain, where the topographic structure may

induce small-scale variations of wind conditions.

Urban background areas are those remote from the influence of small-scale sources, i.e.

from major roads and industrial plants (including power plants, airports, harbours, waste

incinerators).

The optimum tools for the identification of those different types of areas are

(a) an emission database which covers all relevant source categories in appropriate

spatial resolution (i.e. road traffic on street scale and area sources on a resolution of

at least 1 km).

(b) air quality modelling data with an appropriate spatial resolution.

(c) air quality monitoring data from existing or previous measurements.

Monitoring data can originate from continuous air quality measurements or from passive

sampling campaigns.

In addition and in the case that no appropriate air quality information and emission data are

available, complaints of the resident population about smoke, dust or odours annoyance can

be used as indicators for relevant sources. The source height of industrial facilities can be

used as additional indicator.

If such information is not available and also if the above information is available, ―surrogate

(indicator)‖ information as given below has to be used, because all information should be

checked.

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Surrogate/indicator information to assess “hotspots”:

Industrial sources

In case that no emission inventory with detailed information about all relevant industrial

plants is available, the following items should be checked:

- Do possibly relevant industrial plants emit chemical substances relevant with

respect to the AQ Directive?

- Is information related to the implementation of the IPPC Directive available?

- Quantity of emitted pollutants

- Stack height

- Fugitive emission

- Complaints

Road Traffic

The geometry of a road is characterized by the following information:

Ratio of width of road and height of adjacent buildings

Length of the road more then 25 m to next crossroad

Buildings along the road – street canyon; detached buildings, open terrain.

Basic information to assess the importance of the traffic emissions for a certain road:

average daily traffic volume (DTV)

daily and weekly traffic profile

average traffic velocity

frequency of traffic jams, stop and go

fleet composition and age

cold-start contributions

number of motorized two-wheel vehicles

number of buses (diesel, gas)

number of heavy trucks

number of and light trucks

Shipping

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Ship emissions may be relevant near large harbours or near heavily frequented shipping

routes.

It should be noted that emission factors for ship engines by far exceed those of road vehicles

due to high-sulphur fuels and low standard exhaust treatment.

Domestic heating

Type of heat supply – district heating, central heating for the building, single stoves?

Type of heating installation

Type of fuel used

Heated area of the building

Other sources of air pollution:

construction works

airports

harbours

agriculture, including erosion of fields

natural sources (e.g. Sahara dust; forest fires)

Topographic and meteorological information

In order to assess the local and regional transport and dispersion of pollutants and the

impact on resident population, additional relevant information on the meteorological and

geographic conditions is useful.

The topographic structure of the area - hilly, flat, mountainous; near the sea, narrow or wide

valley, basin – exerts a significant influence on transport and dispersion by

transport along valleys

diurnal transport patterns, induced by valley wind systems, slope wind systems or

sea breeze wind systems.

accumulation in basins and valley

To assess transport and dispersion of pollutants, information about wind direction and

velocity – both at ground level, as well as on roof level (in densely built-up areas), and

information on the occurrence, frequency and height of temperature inversions are useful.

High-scale Maps (scale 1:10,000 or 1:25,000), aerial photos, or GIS should in any case be

used as tools for monitoring site selection.

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4. Macro-scale siting criteria for monitoring stations

4.1 Protection of human health

(a) Sampling points directed at the protection of human health shall be sited in such a

way as to provide data on the following:

- the areas within zones and agglomerations where the highest concentrations

(hotspot) occur to which the population is likely to be directly or indirectly exposed

for a period which is significant in relation to the averaging period of the limit

value(s),

- levels in other areas within the zones and agglomerations which are representative

of the exposure of the general population,

(b) Sampling points shall in general be sited in such a way as to avoid measuring very

small micro-environments in their immediate vicinity, which means that a sampling

point must be sited in such a way that the air sampled is representative of air quality

for a street segment no less than 100 m length at traffic-orientated sites and at least

250 m × 250 m at industrial sites, where feasible;

(c) Urban background locations shall be located so that their pollution level is influenced

by the integrated contribution from all sources upwind of the station. The pollution

level should not be dominated by a single source unless such a situation is typical for

a larger urban area. Those sampling points shall, as a general rule, be representative

for several square kilometres;

(d) Where the objective is to assess rural background levels, the sampling point shall not

be influenced by agglomerations or industrial sites in its vicinity, i.e. sites closer than

five kilometres;

(e) Where contributions from industrial sources are to be assessed, at least one sampling

point shall be installed downwind of the source in the nearest residential area. Where

the background concentration is not known, an additional sampling point shall be

situated within the main wind direction;

(f) Sampling points shall, where possible, also be representative of similar locations not

in their immediate vicinity;

(g) Account shall be taken of the need to locate sampling points on islands where that is

necessary for the protection of human health.

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4.2 Protection of vegetation and natural ecosystems

Sampling points targeted at the protection of vegetation and natural ecosystems shall be

sited more than 20 km away from agglomerations or more than 5 km away from other towns,

industrial installations or motorways or major roads with traffic counts of more than 50,000

vehicles per day, which means that a sampling point must be sited in such a way that the air

sampled is representative of air quality in a surrounding area of at least 1000 km².

A Member State may provide for a sampling point to be sited at a lesser distance or to be

representative of air quality in a less extended area, taking account of geographical

conditions or of the opportunities to protect particularly vulnerable areas.

Account shall be taken of the need to assess air quality on islands.

4.3 Protection of human health and vegetation, Ozone

Type of station

Objectives of measurement

Representativeness(1) Macroscale siting criteria

Urban Protection of human health: to assess the exposure of the urban population to ozone, i.e. where population density and ozone concentration are relatively high and representative of the exposure of the general population

A few km² Away from the influence of local emissions such as traffic, petrol stations, etc.; Vented locations where well mixed levels can be measured; Locations such as residential and commercial areas of cities, parks (away from the trees), big streets or squares with very little or no traffic, open areas characteristic of educational, sports or recreation facilities

Suburban Protection of human health and vegetation: to assess the exposure of the population and vegetation located in the outskirts of the agglomeration, where the highest ozone levels, to which the population and vegetation are likely to be directly or indirectly exposed occur

Some tens of km² At a certain distance from the area of maximum emissions, downwind following the main wind direction/directions during conditions favourable to ozone formation; Where population, sensitive crops or natural ecosystems located in the outer fringe of an agglomeration are exposed to high ozone levels; Where appropriate, some suburban stations also upwind of the area of maximum emissions, in order to determine the regional background levels of ozone

Rural Protection of human health and vegetation: To assess the exposure of population, crops and

Sub-regional levels (some hundreds of km²)

Stations can be located in small settlements and/or areas with natural ecosystems, forests or crops;

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Type of station

Objectives of measurement

Representativeness(1) Macroscale siting criteria

natural ecosystems to sub-regional scale ozone concentrations

Representative for ozone away from the influence of immediate local emissions such as industrial installations and roads;

Rural background

Protection of vegetation and human health: To assess the exposure of crops and natural ecosystems to regional-scale ozone concentrations as well as exposure of the population

Regional / national / continental levels (1000 to 10,000 km²)

Station located in areas with lower population density, e.g. with natural ecosystems, forests, at a distance of at least 20 km from urban and industrial areas and away from local emissions; Avoid locations which are subject to locally enhanced formation of ground-near inversion conditions, also summits of higher mountains; Coastal sites with pronounced diurnal wind cycles of local character are not recommended

(1) Sampling points should, where possible, be representative of similar locations not in their

immediate vicinity.

In so far as is practicable the procedure on microscale siting in Section 0 shall be followed,

ensuring also that the air inlet is positioned well away from such sources as furnaces and

incineration flues and more than 10 m from the nearest road, with distance increasing as a

function of traffic intensity.

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5. Micro-scale siting criteria for monitoring stations

5.1 Requirements

In so far as is practicable, the following requirements shall apply:

the flow around the inlet sampling air inlet – except for traffic related stations located

near the building line) shall be unrestricted (free in an arc of at least 270°) without any

obstructions affecting the airflow in the vicinity of the sampler (normally some metres

away from buildings, balconies, trees and other obstacles); the air inlet shall be

located at least 0.5 m from the nearest building in the case of sampling points

representing air quality at the building line),

in general, the inlet sampling point shall be between 1.5 m (the breathing zone) and 4

m above the ground. Higher positions (up to 8 m) may be necessary in some

circumstances. Higher siting may also be appropriate if the station is representative of

a large area, or to compare with a site in a street canyon.

the inlet probe shall not be positioned in the immediate vicinity of sources in order to

avoid the direct intake of emissions unmixed with ambient air,

the sampler‘s exhaust outlet shall be positioned so that recirculation of exhaust air to

the sampler inlet is avoided,

for all pollutants, traffic-orientated sampling probes shall be at least 25 m from the

edge of major junctions and no more than 10 m from the kerbside,

The following factors may also be taken into account:

interfering sources,

security,

access,

availability of electrical power and telephone communications,

safety of the public and operators,

the desirability of co-locating sampling points for different pollutants,

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5.2 Documentation and review of site selection

The site-selection procedures shall be fully documented at the classification stage by such

means as compass-point photographs of the surrounding area and a detailed map. Sites

shall be reviewed at regular intervals with repeated documentation to ensure that selection

criteria remain valid over time.

Measurement procedure for the determination of Particulate Matter and air component concentrations

Content

Page

Contents 77

1 Scope, Operating range, Measurement procedure, Control procedure features, Responsibilities 79

2 Devices 80

3 Sampling 80

4 Description of measurement procedure 81

5 Device settings 81 5.1 Measuring devices: 81 5.2 Measurement data collection: measurement data interface Orion 81 5.3 Measurement data collection: Orion Software 81 5.4 Data communication software Orion 82

6 Documentation 82

7 Quality assurance measures 82

8 Device maintenance, maintenance intervals, intervention criteria 83

9 Disposal of samples, reagents and standards 83

10 Deviation from the standards 83

11 Flow chart 84

78

79

1 Scope, Operating range, Measurement procedure, Control procedure features, Responsibilities

These procedure instructions are valid for the execution of automatic air quality measurements in the monitoring network on B. As a basis, the following standards were used: DIN EN 14 211 Ambient-air quality – Standard method for the measurement of

the concentration of nitrogen dioxide and nitrogen monoxide by chemiluminescence

DIN EN 14 212 Ambient-air quality – Standard method for the measurement of the concentration of sulphur dioxide by ultraviolet fluorescence

DIN EN 14 625 Ambient-air quality - Standard method for the measurement of the concentration of ozone by ultraviolet photometry

DIN EN 14 626 Ambient-air quality - Standard method for the measurement of the concentration of carbon monoxide by nondispersive infrared spectroscopy

DIN EN 14 662 Ambient-air quality - Standard method for measurement of benzene concentrations

DIN EN 12341 Air quality - Determination of the PM10 fraction of suspended particulate matter

DIN EN 14907Ambient air quality - Standard gravimetric measurement method for the determination of the PM2,5 mass fraction of suspended particulate matter The technical equipment and its parameterisation are described starting from the sampling device in the monitoring station to the data transfer in the raw-value table of the database in the monitoring network centre. The characteristics laid down in the following Daughter Directives are used as control features: 1999-30-EC Daughter Directive NOx, SO2, particles 2000-69-EC Daughter Directive CO, BTX 2002-3-EC Daughter Directive O3 The concentration of gas components are indicated in µg/m³, related to 293°K and 101,3 kPa Minimum data collection: > 90 % Measurement uncertainty in 95% confidence interval: inorg. components< 15 % Measurement uncertainty in 95% confidence interval: org. components< 25 % Measurement uncertainty in 95% confidence interval: PM10; PM25 < 25 % Responsible:

80

Operation Head of monitoring network service

Maintenance Maintenance employee in monitoring network service department

Calibration Calibration lab employee Repairs Repairs employee in monitoring network

service department Calibration standards

Head of calibration lab

2 Devices

Hardware: Analysers: NOx ML9841B IZS Permeation SO2 ML9850B IZS Permeation O3 ML9811B IZS O3-Generator CO ML9830B. Ext. test gas bottle BTX GC Thermo-desorption. ext. test gas bottle

PM10 Nephelometer with subsequently switched on Low Volume Sampler for aprox. 20 filters. The volume (2,3m³/h) is related to current conditions

Station- PC Voltage stabiliser and uninterruptible power source (UPS) for the PC. Data interface for serial/analogue data acquisition. Data transfer device GSM radio modem Data centre, composed of a PC and the necessary communication equipment.

Standard software:

Operating system Windows Commercial software:

Measurement data collection software From raw value to average value Data communication programme GSM Monitoring network centre software Data download, validation

data release to the national centre and remote maintenance

3 Sampling

In the monitoring stations there are sampling systems for gaseous components with pre-suction and gas distributor according to the standards mentioned before (material, time spent by gas in sampling system shorter than 5 seconds). The sampling system can be heated. The dust sampling is a part of dust measuring devices according to their build-up.

81

4 Description of measurement procedure

The measurements are performed in air-conditioned measurement containers with external sampling equipment. The measurement devices suck the sample air through the sample-gas distributor from the sampling equipment. The output signals of the measurement device are taken over analogue or digitally through the data interface Orion or directly through the serial interface of the station computer. The measurement data collection software Orion calculates measurement values from the electric signals, taking into consideration the scaling. These measurement values are used to calculate 1-hour average values, taking into consideration the error status. In this time, the validity of each sampling value is verified.

Each calibratable analyser is verified automatically in a 25-hour-cycle. The result of the verification is not used for the calculation of the measurement value. The result of the 1-hour-average value calculation and that of the 25-hour operation control are saved.

On demand from the monitoring network centre, the communication software selects files and turns the measurement, status or calibration values over to the monitoring network centre. Changes in the parameterization of the data collection software can be performed locally or remotely by means of Orion. Additionally, changes are recorded in the station diary and the logbook of the monitoring network centre. As these works concern the operation of the regional monitoring network, they are performed by the monitoring network centre of the respective monitoring network on own account.

5 Device settings

5.1 Measuring devices:

On the commissioning, the device parameters are established and are documented in the station manual. The parameters recommended by the producer shall be used. The concentration of gas analysers are set to be related to standard conditions of 293 K (equivalent of 20°C) and 101,3 kPa. The concentration of particulate matter measuring devices has to be rendered related to current operation conditions.

5.2 Measurement data collection: measurement data interface Orion

Analogue/Digital converter with status recording.

5.3 Measurement data collection: Orion Software

Measurement data can be read through the measurement data interface Orion. The measurement values are interrogated, recalculated into µg/m³ and then turned into 1-hour- average values. At the commissioning of a new analyser, the parameters for data collection and data channels are set and recorded in the station book.

Function control

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For inorganic gas components, a function control is performed automatically every 25 hours. There is no subsequent correction of measured values on the basis of the results. The intervention criteria for the running of the monitoring network service are named in the standards listed in chapter 1. Function control for BTX analysers shall be performed manually.

5.4 Data communication software Orion

Data communication is constructed as GSM radio network.

6 Documentation

Documents relevant for the monitoring network shall be administered in the following locations: Folder Room Documentation from: Form folder XXX Forms for maintenance, calibration, fault message, repairs, device exchange and testing agents Testing agents XXX Testing deadlines and test execution. Station book XXX Device parameters and data collection

parameters, maintenance works

Repairs Calibrations and calibration parameters Maintenance history files XXX Procurement, commissioning, location

and collection of all repairs protocols Calibration folder XXX Calibration results Maintenance folder XXX Maintenance protocols. Fault message folder XXX Faults which occurred in the monitoring

network and their reporting to the head of monitoring network service

Device exchange XXX Change of a faulty device Interlaboratory test folderXXX Results of interlaboratory tests All works performed in a monitoring network station are recorded in the diary. A copy is filed yearly in the monitoring network centre. The exchange of measurement devices and woks at the calibration system are notified to the head of monitoring network service Level B by means of an adequate form and lead to a calibration on site. Faults occurred in the monitoring network stations are recorded in the faults protocol and are passed on to the head of the monitoring network service. The originals of the instruction manuals for measurement devices and for the software are stored in room XXX.

7 Quality assurance measures

Daily function control NOx, SO2, O3, CO Function control if required, at least after 14 days: BTX Monthly maintenance SOP Maintenance Quarterly control calibration SOP Calibration [component]

83

Measurement device verifications after repairs SOP Repairs After commissioning or exchange of an analyser respectively after the exchange of measurement data collection components, it must be ensured, that the measured value in the measurement data collection software corresponds to the measured value displayed by the analyser.

8 Device maintenance, maintenance intervals, intervention criteria

The field operation and the ongoing quality control for the above mentioned components is regulated in the EN standards. The performing of the maintenance is regulated in the SOP Maintenance

9 Disposal of samples, reagents and standards

The safety data sheets for the used chemicals are to be stored in such a way as to be accessible for the technicians.

10 Deviation from the standards:

Standard: 9.5 calibration of the measurement device Measurement devices shall not be resettled in the field…...

Level B: the calibration in the filed is not a problem. If necessary, measurement devices are re-calibrated in the field by the monitoring network service in Level B.

Standard: 11.2.3 Reports regarding air quality data Specification of data measurement uncertainty.

Level B: The measurement uncertainty calculations are only performed when enough experience has been accumulated with regard to the operation of the monitoring network.

84

11 Flow chart

Monitoring network service

Content

1 Scope, responsibilities, measurement procedures 86

2 Measurement, results 86

3 Monitoring network service 86

4 Execution of maintenance operations 86

5 Performing of routine calibrations 86

Sampling

Measurement

Data collection

Orion

Average determination

Storage

ext. pump and gas

distributor

1h

t < 5sek

dP < 2hPa

Interrogation cycle

? sek

1h Status Cal.

Approved analyser

Data provision

software Orion

GSM Modem

Data transfer to the data centre

1h Kal

Raw values

Data

processing 1h

85

6 Malfunction removal, repairs 87

7 Devices and chemicals 87

8 Protocols 88

9 Quality assurance measures 88

10 Disposal of samples, reagents and standards 88

86

1 Scope, responsibilities, measurement procedures This Procedure Instruction is valid for the calibration, maintenance and repair of online operated monitoring stations. All maintenance operations with time intervals of more than 2 weeks are performed in principle by the employees. For calibration, the monitoring network stations are called on by employees at least every 3 months. Part of the field of activity are the location (park, ring fence), the monitoring station (cleaning, air-conditioning, sampling system), power supply, analysers, measurement data collection systems and communication systems. The locations, the measurement period and the analyser placement are documented in the monitoring network centre. The monitoring network is divided into three organisation units: Monitoring network centre Validation, data transfer, data provision Monitoring network service Maintenance, calibration, repairs, fault clearance

Calibration lab backup of gas standards and determination of transfer

standards, gravimetric analysis PM10, PM2,5

2 Measurement, results The measurements are performed in the monitoring network stations. The measured values are recalled and validated by the monitoring network centre and forwarded to National Data Centre. Malfunctions and conspicuous elements in the measured values are notified to the head of the monitoring network service and lead to a service intervention.

3 Monitoring network service

Every day, the measurement data is recalled by each monitoring station in the monitoring network and are validated in the monitoring network centre The following situations make the intervention of monitoring network service necessary: Routine maintenance Routine calibration Malfunctions which require repairs Deviation of function control results Conspicuous elements in the execution of control calibration Data malfunction Implausible measured values Status messages The execution of tasks is described in the following.

4 Execution of maintenance operations

The maintenance operations are executed in a determined cycle. The maintenance plan is the basis for this.

5 Performing of routine calibrations

Routine calibrations are performed for all components every three months.

87

The transfer standards used for that must have been verified in the previous 6 months according to EN Standards; it is however recommendable to verify the transfer standards before their use in the laboratory.

6 Malfunction removal, repairs

Malfunctions are notified to the head of monitoring network service by means of an error notification form. The successful malfunction removal is notified to the monitoring network centre. Should the malfunction removal not be possible in the monitoring network station, then the repairs are performed in the workshop of the monitoring network centre. Before the use of a newly repaired analyser, is has to be subjected to verification. This verification includes at least a basic calibration and a linearity test and is performed by the calibration lab.

7 Devices and chemicals

Monitoring network station: Automatic air quality monitoring station, that must be calibrated, maintained and repaired regularly. For each monitoring network station a history folder is created.

Analysers: For the execution of the air pollutant analysis. For each analyser, a history folder is created.

Devices: For the repair and maintenance operations, several verification devices are used: e.g. electric measurement devices for power and voltage measurement, physical devices for measurement of flow, pressure, temperature, etc. These devices are listed in the folder ―Verification tools‖. Verifications, repairs and maintenance operations are documented here. The type and cycle of verifications are provided in the device folder. For reference devices a history folder is created.

Transfer standards: The transfer standards needed for calibration, maintenance, and repairs are subjected to a monthly check in the calibration lab. The type and cycle of these verifications are provided in the device folder. For each transfer standard a history folder is created.

Chemicals: The chemicals named by the device producer are to be used in maintenance operations. The exchange period is inidcated in the maintenance plan.

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8 Protocols

All operations performed are documented by means of predetermined forms. The forms are documents also applicable of the SOPs

9 Quality assurance measures

All transfer standards and verification tools used in monitoring network service are verified regularly. In principle, adequate transport containers are to be used. All valid rules are to be obeyed. The staff is trained regularly.

10 Disposal of samples, reagents and standards

The safety data sheets must be stored so as to be accessible to technicians. Chemicals are disposed of according to instructions in the safety data sheet and the disposal plan. Permeation tubules or wafers are disposed of to the metal scrap heap after piercing of the membrane. Empty bottles are returned to the producer.

Execution of Maintenance Works

Content

1 Scope, Field of Activity, Measuring Procedure, Control Process Data, Responsibilities 89

2 Maintenance protocol 89

3 Execution of Maintenance Works 89

4 Equipment Settings 90

5 Evaluation, Results, Documentation 90

6 Quality Assurance Measures 90

7 Disposal of Samples, Reagents and Standards 90

89

12 Scope, Field of Activity, Measuring Procedure, Control Process Data, Responsibilities

This SOP applies to the execution of maintenance works in the air monitoring network and refers to the monitoring stations of the monitoring networks and to the calibration lab. The maintenance works shall be carried out in the established cycle. The basis for the works that are to be carried out are the requirements from the relevant EN norms and instruction manuals of the devices, as well as the works considered to be necessary according to the own experience. The maintenance serves the preservation of the functional capacity, the timely detection of malfunctioning and the observance of the quality requirements of the framework directive on air quality. Responsible with the works is the head of the monitoring network service.

13 Maintenance protocol

For each equipment that has to be maintained a maintenance protocol has to be drafted. This maintenance protocol contains the type of equipment, the serial number and the list of the works to be carried out. The maintenance is divided into various maintenance types, i.e.:

Monthly maintenance simple maintenance works, filter replacement, testing parameters settings, etc.

Quarterly maintenance testing of zero gas submissions, cleaning of the station, etc. Bi-annual maintenance cleaning the air conditioning, cleaning the sampling system, etc. Yearly maintenance maintenance of the exterior installation, replacement of air filters, etc. In addition to the works to be carried out, the consumables have to be mentioned. The maintenance has to be recorded into the station log book, the filled in maintenance protocol shall be included in the folder of maintenance protocols in the monitoring network centre.

14 Execution of Maintenance Works

Prior to the beginning of the maintenance works the head of the monitoring network service informs the monitoring network centre about the execution of the upcoming maintenance. The analysers shall be turned on "Out of Service" in order to discard the following measured values. The works foreseen in the maintenance plan shall be carried out. Upon finalisation of the works one must wait half an hour before switching the analysers on "Measuring", in order for the new filters to be coordinated with the intaken monitored air. In the meantime the maintenance shall be recorded in the station log book. After the coordination period an automatic function control has to be carried out. The monitoring network centre shall be informed before the finalisation of the maintenance works.

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15 Equipment Settings

The parameters relevant to the measurement shall be noted in the maintenance template during the maintenance and their plausibility shall be verified. Problems shall be noted on the template and the head of the monitoring network service shall be notified thereof.

16 Evaluation, Results, Documentation

An evaluation shall be carried out by the head of the monitoring network station. For example, the pressures of the test gas cylinders shall be evaluated for ordering new gasses and the timely replacement of the cylinders shall be organized. The filled in maintenance protocol shall be filed in the maintenance protocol folder in the monitoring network centre.

17 Quality Assurance Measures

At the end of the month is shall be controlled whether all the maintenance works were carried out according to their schedule.

18 Disposal of Samples, Reagents and Standards

The safety data sheet for the used chemicals has to be stored in an accessible manner for the technicians, according to the disposal concept.

Calibration of NO/NOx analyzers

Content

1 Scope, Process Features 91

2 Equipment and calibration gases 91

3 Preparation 91

4 Execution of the calibration 91 4.1 Test gas cylinder 92 4.2 Dilution system with GPT 92 4.3 Converter verification 93 4.4 Establishing the control value of the test gas for the functional control 93

5 Evaluation and documentation 93

6 Quality Assurance Measures 93

91

19 Scope, Process Features

This SOP is applicable to the calibration of NO/NO2 analyzers in the automatic air monitoring networks. The basis for the calibration is the European Norm EN 14211. Calibration Cycle 3 months Concentration about 80% of the certification range Extended uncertainty of the span gas < 5% Purity of the zero gas <detection limit of the analyzer The employees of the air quality monitoring station are responsible with carrying out the calibrations.

20 Equipment and calibration gases

Zero gas: Gas cylinder with synthetic air or zero gas collection (purafil and active carbon) Span gas: Gas cylinder with test gas NO in N2 (about 300 ppb; 375 µg/m³ ) or Dilution system with ozone generator (GPT: gas phases titration) and zero gas production, Rotameter

21 Preparation

In the laboratory Print NO calibration form. Check whether the transfer standard (zero, span) was certified again within the past

6 months in the test gas lab. In the certificate the NO and NO2 concentration must be mentioned.

In the station Gas cylinder Screw the pressure gas regulator on the gas cylinder and ventilate it 3 times. Dilution system with GPT Ventilate the gas pipe from the test gas cylinder to the dilution module 3 times.. Let the dilution module warm up for at least 60 min.

22 Execution of the calibration

In the container set the ML9841B analyzer on "Out of Service", the measured values are now marked with a functioning status and thus will not go into the subsequent evaluation. Then fill in the calibration form (station, analyzer SN, date, zero test value, span test value). The equipment settings (offset, span) are to be noted for the measurement channels NO and NOx before and after the calibration. The test gas must be released without pressure, i.e. the unnecessary test gas has to be able to flow off through a bypass connection. For the control of the surplus, check the surplus with a Rotameter.

92

22.1 Test gas cylinder

Zero gas: Take the sampler tube off the test gas distributor and connect it to the zero gas cylinder or the zero gas collection. After 30 minutes of warm up read the average value of the last 3 minutes from the data capture program and note it into the field Actual Value Zero.

For variations <5µg/m³ the zero point of the measurement channels NO and NOx has to be setup again according to the directions from the equipment manual. For variations >5µg/m³ the production of zero gas of the analyzer and of the transfer standard have to be checked.

Span gas: Connect the sampler tube to the pressure gas controller and set the surplus to

0.5 l/min. After 30 minutes of warm up read the average value of the last 3 minutes from the data capture program and note it into the field Actual Value Span.

For variations <10% of the control value the increase (span) of the measurement channels NO and NO x (NO x corresponds to the sun of NO+NO2 of the calibration lab certificate (in ppb)) according to the directions of the equipment manual. For variation >10% of the control value the analyzer shall not be calibrated again before finding the reason for the variation. Usually the transfer standard and the analyzer must be checked.

22.2 Dilution system with GPT

Zero gas: Take the sampler tube off the test gas distributor and connect it to the dilution system. Set the dilution system to "zero gas". After 30 minutes of warm up read the average value of the last 3 minutes from the data capture program and note it into the field Actual Value Zero.

For variations <5µg/m³ the zero point of the measurement channels NO and NOx has to be setup again according to the directions from the equipment manual.

For variations >5µg/m³ the zero gas production of the analyzer and the transfer standard are to be checked.

Span gas

Set the dilution system to "span gas". After 30 minutes of warm up read the average value of the last 3 minutes from the data capture program and note it into the field Actual Value Span. For variations <10% of the control value the increase (span) of the measurement channels NO and NO x (NO x corresponds to the sun of NO+NO2 of the calibration lab certificate (in ppb)) according to the directions of the equipment manual.

For variation >10% of the control value the analyzer shall not be calibrated again before finding the reason for the variation. Usually the transfer standard and the analyzer must be checked.

93

22.3 Converter verification

Once a year the verification of the efficiency of the converter is foreseen. The efficiency can only be tested with a portable GPT (dilution system with ozone generator). When the efficiency of the converter is <95%, the analyzer must be checked, or renewed, as the case may be. The execution is described in the EN 14211 Chapter 8.4.14. From our experience we recommend a verification of the efficiency of the converter every half a year.

22.4 Establishing the control value of the test gas for the functional control

When the calibration is closed, the sampler tube has to be reconnected to the sampler distributor. The analyser will be operated again in the monitoring station and next the functional control is released. After the conclusion of the functional control the measured value of the span gas shall be introduced into the station computer as control value for NOx

.

23 Evaluation and documentation

The calibration shall be recorded in the station logbook. The data transmitted in the measurement station will be transferred into an Excel spreadsheet for subsequent evaluation. The calibration form shall be stored in the calibration folder at the center of the

monitoring network. In case of conspicuous events during the calibration the manager of the monitoring

network shall be informed.

24 Quality Assurance Measures

The transfer standards are to be certified regularly in the calibration lab. The control value is standardised to 293 K and 101.1 kPa. The calibration certificate will be attached to the transfer standard. The maintenance of the control equipment and of the transfer standards shall be ensured through the monitoring network.

Calibration of SO2 Analyzers

Content

1 Scope, Process Features 95

2 Equipment and calibration gases 95

94

3 Preparation 95

4 Execution of the calibration 96 4.1 Test gas cylinder 96 4.2 Dilution system 96 4.3 Permeation system 98 4.4 Establishing the control value of the test gas for the functional control 98

5 Evaluation and documentation 98

6 Quality Assurance Measures 98

95

25 Scope, Process Features

This SOP is applicable to the calibration of SO2 analyzers in the automatic air monitoring networks. The basis for the calibration is the European Norm EN 14212. Calibration Cycle 3 months Concentration about 80% of the certification range Extended uncertainty of the span gas < 5% purity of the zero gas <detection limit of the analyzer The employees of the air quality monitoring station are responsible with carrying out the calibrations.

26 Equipment and calibration gases

Zero gas: Gas cylinder with synthetic air or zero gas collection (active carbon) Span gas: Gas cylinder with test gas SO2 in air (300 ppb; 800 µg/m³ ) or Dilution system with zero gas production or Permeation system with zero gas production and minimum, maximum thermometer at the permeation oven. Rotameter

27 Preparation

In the laboratory Print calibration form for SO2.

Check whether the transfer standard (zero, span) was certified again within the past 6 months in the test gas lab.

The min. max. display of the thermometer of the permeation system must be set back.

In the station Gas cylinder Screw the pressure gas regulator on the gas cylinder and ventilate it 3 times. Dilution system Ventilate the gas pipe from the test gas cylinder to the dilution module 3 times.. Let the dilution module warm up for at least 60 min. Permeation system

Check the temperature of the permeation kiln, the min/max temperature must not exceed +5% of the control temperature of the permeation kiln.

Setup the certified concentration.

96

28 Execution of the calibration

In the container set the ML9850B analyzer on "Out of Service", the measured values are now marked with a functioning status and thus will not go into the subsequent evaluation. Then fill in the calibration form (station, analyzer SN, date, zero test value, span test value, min. max temperature, when using a permeation system) Note in the calibration form the settings of the equipment (offset, span) before and after the calibration. The test gas must be released without pressure, i.e. the unnecessary test gas has to be able to flow off through a bypass connection. For the control of the surplus, check the surplus with a Rotameter.

28.1 Test gas cylinder

Zero gas: Take the sampler tube off the test gas distributor and connect it to the zero

gas cylinder or the zero gas collection. After 30 minutes of warm up read the average value of the last 3 minutes from the data capture program and note it into the field Actual Value Zero.

For variations <5µg/m³ the zero point has to be setup again according to the directions from the equipment manual. For variations >5µg/m³ the production of zero gas of the analyzer and of the transfer standard have to be checked.

Span gas Connect the sampler tube to the pressure gas controller and set the surplus to

0.5 l/min. After 30 minutes of warm up read the average value of the last 3 minutes from the data capture program and note it into the field Actual Value Span.

For variations <10% of the control value the increase (span) has to be setup again according the directions of the equipment manual.

For variations >10% of the control value the analyzer is not recalibrated, before identifying the reason for the variations (the transfer standards and the analyzer have to be checked).

28.2 Dilution system

Zero gas: Take the sampler tube off the test gas distributor and connect it to the dilution system. Set the dilution system to "zero gas". After 30 minutes of warm up read the average value of the last 3 minutes from the data capture program and note it into the field Actual Value Zero.

For variations <5µg/m³ the zero point has to be setup again according to the directions from the equipment manual. For variations >5µg/m³ the production of zero gas of the analyzer and of the transfer standard have to be checked.

Span gas Set the dilution system to "span gas". After 30 minutes of warm up read the

average value of the last 3 minutes from the data capture program and note it into the field Actual Value Span.

97

For variations <10% of the control value the increase (span) has to be setup again according the directions of the equipment manual.

For variations >10% of the control value the analyzer is not recalibrated, before identifying the reason for the variations (the transfer standards and the analyzer have to be checked).

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28.3 Permeation system

Zero gas: Take the sampler tube off the test gas distributor and connect it to the

permeation system. Set the permeation system to "zero gas". After 30 minutes of warm up read the average value of the last 3 minutes from the data capture program and note it into the field Actual Value Zero.

For variations <5µg/m³ the zero point has to be setup again according to the directions from the equipment manual. For variations >5µg/m³ the production of zero gas of the analyzer and of the transfer standard have to be checked.

Span gas Set the permeation system to "span gas". After 30 minutes of warm up read

the average value of the last 3 minutes from the data capture program and note it into the field Actual Value Span.

For variations <10% of the control value the increase (span) has to be setup again according the directions of the equipment manual.

For variations >10% of the control value the analyzer is not recalibrated, before identifying the reason for the variations (the transfer standards and the analyzer have to be checked).

28.4 Establishing the control value of the test gas for the functional control

When the calibration is closed, the sampler tube has to be reconnected to the sampler distributor. Operate the analyzer in the station and release the functional control. After the conclusion of the functional control the measured value of the span gas shall be introduced into the station computer as control value.

29 Evaluation and documentation

The calibration shall be recorded in the station logbook. The data transmitted in the measurement station will be transferred into an Excel spreadsheet for subsequent evaluation. The calibration form shall be stored in the calibration folder at the center of the

monitoring network. In case of conspicuous events during the calibration the manager of the monitoring

network shall be informed.

30 Quality Assurance Measures

The transfer standards are to be certified regularly in the calibration lab. The control value is standardised to 293 K and 101.1 kPa. The calibration certificate will be attached to the transfer standard. The maintenance of the control equipment and of the transfer standards shall be ensured through the monitoring network.

SO2 -Verification Date:

99

Station:

Testing medium No.:

Device type:

Device No.:

Transfer Analyser

Set point [µg/m³] Before correction [µg/m³] After correction [µg/m³]

0

Before After

Offset:

Slope:

Internal test gas IZS

calibration values: [µg/m3]

Before: µg/m3

After: µg/m3

Temp. during transport

Min Max

Outward journey

Journey back

Calibration O.K. YES/NO Signature:___________________

Notes:

100

Calibration of O3 Analyzers

Content

1 Scope, Process Features 101

2 Equipment and calibration gases 101

3 Preparation 101

4 Execution of the calibration 101 4.1 ozone generator 101 4.2 Establishing the control value of the test gas for the functional control 102

5 Evaluation and documentation 102

6 Quality Assurance Measures 102

101

31 Scope, Process Features

This SOP is applicable to the calibration of O3 analyzers in the automatic air monitoring networks. The basis for the calibration is the European Norm EN 14625. Calibration Cycle 3 months Concentration about 80% of the certification range or

within the range of the 1h limit value (240 µg/m³)

Extended uncertainty of the span gas < 5% Purity of the zero gas <detection limit of the analyzer The employees of the air quality monitoring station are responsible with carrying out the calibrations.

32 Equipment and calibration gases

ozone generator with zero gas production

33 Preparation

In the laboratory Print calibration form for O3.

Check whether the transfer standard (zero, span) was certified again within the past 6 months in the test gas lab.

In the station Let the ozone generator warm up for at least 60 min. Setup the concentration certified in the calibration lab.

34 Execution of the calibration

In the container set the ML9811B analyzer on "Out of Service", the measured values are now marked with a functioning status and thus will not go into the subsequent evaluation. Then fill in the calibration form (station, analyzer SN, date, zero test value, span test value) Note in the calibration form the settings of the equipment (offset, span) before and after the calibration. The test gas must be released without pressure, i.e. the unnecessary test gas has to be able to flow off through a bypass connection. For the control of the surplus, check the surplus with a rotameter.

34.1 ozone generator

Zero gas: Take off the sampler tube from the test gas distributor and connect it to the test gas exit of the ozone generator. Setup the ozone generator to zero gas with the help of the manual. After 30 minutes of warm up read the average value of the last 3 minutes from the data capture program and note it into the field Actual Value Zero.

For variations <5µg/m³ the zero point has to be setup again according to the directions from the equipment manual. For variations >5µg/m³ the production of zero gas of the analyzer and of the transfer standard have to be checked.

102

Span gas Setup the ozone generator to zero gas with the help of the manual. After 30 minutes of warm up read the average value of the last 3 minutes from the data capture program and note it into the field Actual Value Span.

For variations <5 % of the control value the increase (span) has to be setup again according the directions of the equipment manual.

For variations >5 % of the control value the analyzer is not recalibrated, before identifying the reason for the variations (the transfer standards and the analyzer have to be checked).

34.2 Establishing the control value of the test gas for the functional control

When the calibration is closed, the sampler tube has to be reconnected to the sampler distributor. Operate the analyzer in the station and release the functional control. After the conclusion of the functional control the measured value of the span gas shall be introduced into the station computer as control value.

35 Evaluation and documentation

The calibration shall be recorded in the station logbook. The data transmitted in the measurement station will be transferred into an Excel spreadsheet for subsequent evaluation. The calibration form shall be stored in the calibration folder at the center of the

monitoring network. In case of conspicuous events during the calibration the manager of the monitoring

network shall be informed.

36 Quality Assurance Measures

The transfer standards are to be certified regularly in the calibration lab. The control value is standardised to 293 K and 101.1 kPa. The calibration certificate will be attached to the transfer standard. The maintenance of the control equipment and of the transfer standards shall be ensured through the monitoring network.

O3-Verification Date:

Station:

Testing medium No.:

Device type:

103

Device No.:

Set point Measured

value Default value [X]

ppb Before correction

[ppb] ppb

0

Before After

Offset:

Span:

Internal test gas O3 calibration values: [µg/m3]

Before: µg/m3 After:

Notes:

Calibration OK YES/NO

Signature:___________________

Calibration of CO Analyzers

Content

1 Scope, Process Features 105

2 Equipment and calibration gases 105

3 Preparation 105

104

4 Execution of the calibration 105 4.1 Test gas cylinder 106 4.2 Dilution system 106 4.3 Establishing the control value of the test gas for the functional control 106

5 Evaluation and documentation 107

6 Quality Assurance Measures 107

105

37 Scope, Process Features

This SOP is applicable to the calibration of CO analyzers in the automatic air monitoring networks. The basis for the calibration is the European Norm EN 14626. Calibration Cycle 3 months

Concentration about 80% of the certification range or within the concentration range of the highest measured concentrations.

Extended uncertainty of the span gas < 5% Purity of the zero gas <detection limit of the analyzer The employees of the air quality monitoring station are responsible with carrying out the calibrations.

38 Equipment and calibration gases

Zero gas: gas cylinder with synthetic air or zero gas collection (silicagel and hopcalite) Span gas: gas cylinder with test gas CO in the air (about 10 ppm: 11.6 mg/m³ ) or Dilution system with zero gas production Rotameter

39 Preparation

In the laboratory Print CO calibration form.

Check whether the transfer standard (zero, span) was certified again within the past 6 months in the test gas lab.

In the station Gas cylinder Screw the pressure gas regulator on the gas cylinder and ventilate it 3 times. Dilution system Ventilate the gas pipe from the test gas cylinder to the dilution module 3 times.. Let the dilution module warm up for at least 60 min.

40 Execution of the calibration

In the container set the ML9830B analyzer on "Out of Service", the measured values are now marked with a functioning status and thus will not go into the subsequent evaluation. Then fill in the calibration form (station, analyzer SN, date, zero test value, span test value) Note in the calibration form the settings of the equipment (offset, span) before and after the calibration. The test gas must be released without pressure, i.e. the unnecessary test gas has to be able to flow off through a bypass connection. For the control of the surplus, check the surplus with a rotameter.

106

40.1 Test gas cylinder

Zero gas: Take the sampler tube off the test gas distributor and connect it to the zero

gas cylinder or the zero gas collection. After 15 minutes of warm up read the average value of the last 3 minutes from the data capture programme and note it into the field Actual Value Zero.

For variations <1µg/m³ the zero point has to be setup again according to the directions from the equipment manual. For variations >1µg/m³ the production of zero gas of the analyzer and of the transfer standard have to be checked.

Span gas Connect the sampler tube to the pressure gas controller and set the surplus to

0.5 l/min. After 15 minutes of warm up read the average value of the last 3 minutes from the data capture program and note it into the field Actual Value Span.

For variations <10% of the control value the increase (span) has to be setup again according the directions of the equipment manual.

For variations >10% of the control value the analyzer is not recalibrated, before identifying the reason for the variations (the transfer standards and the analyzer have to be checked).

40.2 Dilution system

Zero gas: Take the sampler tube off the test gas distributor and connect it to the dilution

system. Set the dilution system to "zero gas". After 15 minutes of warm up read the average value of the last 3 minutes from the data capture programme and note it into the field Actual Value Zero.

For variations <1µg/m³ the zero point has to be setup again according to the directions from the equipment manual. For variations >1µg/m³ the production of zero gas of the analyzer and of the transfer standard have to be checked.

Span gas Set the dilution system to "span gas". After 15 minutes of warm up read the

average value of the last 3 minutes from the data capture programme and note it into the field Actual Value Span.

For variations <10% of the control value the increase (span) has to be setup again according to the directions of the equipment manual.

For variations >10% of the control value the analyzer is not recalibrated, before identifying the reason for the variations (the transfer standards and the analyzer have to be checked).

40.3 Establishing the control value of the test gas for the functional control

When the calibration is closed, the sampler tube has to be reconnected to the sampler distributor. Operate the analyzer in the station and release the functional control. After the conclusion of the functional control the measured value of the span gas shall be introduced into the station computer as control value.

107

41 Evaluation and documentation

The calibration shall be recorded in the station logbook. The data transmitted in the measurement station will be transferred into an Excel spreadsheet for subsequent evaluation. The calibration form shall be stored in the calibration folder at the centre of the

monitoring network. In case of conspicuous events during the calibration the manager of the monitoring network shall be informed.

42 Quality Assurance Measures

The transfer standards are to be certified regularly in the calibration lab. The control value is standardised to 293 K and 101.1 kPa. The calibration certificate will be attached to the transfer standard. The maintenance of the control equipment and of the transfer standards shall be ensured through the monitoring network.

CO-Verification Date:

Station:

Device type:

Device No.:

Transferstandard Analyser

Set point [mg] Before correction [mg]

0

Before

Offset:

Slope:

108

Calibration of BTX Analyzers

Content

1 Scope, Process Features 109

2 Equipment and calibration gases 109

3 Preparation 109

4 Execution of the calibration 110 4.1 Test gas cylinder 110 4.2 Dilution system 111 4.3 Permeation system 111 4.4 Establishing the control value of the test gas for the functional control 111

5 Evaluation and documentation 112

6 Quality Assurance Measures 112

Test gas function control calibration values: [mg/m3]

Before: mg/m3

Calibration OK YES/NO

Notes:

109

43 Scope, Process Features

This SOP is applicable to the calibration of BTX analyzers in the automatic air monitoring networks. The basis for the calibration is the European Norm EN 14662. Calibration Cycle 3 months

Concentration about 80% of the certification range or within the range of the highest expected concentrations.

Extended uncertainty of the span gas < 5% purity of the zero gas <detection limit of the analyzer The employees of the air quality monitoring station are responsible with carrying out the calibrations.

44 Equipment and calibration gases

Zero gas: Gas cylinder with synthetic air or zero gas collection (active carbon) Span gas: Gas cylinder with test gas benzene, toluene and xylene in air (about 20 µg/m³) or Dilution system with zero gas production or Permeation system with zero gas production and minimum, maximum thermometer at the permeation oven. Rotameter

45 Preparation

In the laboratory Print BTX calibration form.

Check whether the transfer standard (zero, span) was certified again within the past 6 months in the test gas lab.

The min. max. display of the thermometer of the permeation system must be set back.

In the station Gas cylinder Screw the pressure gas regulator on the gas cylinder and ventilate it 3 times. Dilution system Ventilate the gas pipe from the test gas cylinder to the dilution module 3 times. Let the dilution module warm up for at least 60 min. Permeation system Check the temperature of the permeation kiln, the min/max temperature must

not exceed +5% of the control temperature of the permeation kiln. Setup the certified concentration.

110

46 Execution of the calibration

In the container set the BTX analyzer on "Out of Service", the measured values are now marked with a functioning status and thus will not go into the subsequent evaluation. Then fill in the calibration form (station, analyzer SN, date, zero test value, span test value, min. max temperature, when using a permeation system) Note in the calibration form the settings of the equipment (response factor) before and after the calibration. The test gas must be released without pressure, i.e. the unnecessary test gas has to be able to flow off through a bypass connection. For the control of the surplus, check the surplus with a rotameter.

46.1 Test gas cylinder

Zero gas: Take the sampler tube off the test gas distributor and connect it to the zero

gas cylinder or the zero gas collection. After 3 cycles read the measured value in the data processing program and note Zero in the actual value field.

For variations <0,5µg/m³ the zero point has to be setup again according to the directions from the equipment manual. For variations >0,5µg/m³ the production of zero gas of the analyzer and of the transfer standard have to be checked.

Span gas Connect the sampler tube to the pressure gas controller and set the surplus to

0.5 l/min. After 3 cycles read the measured value in the data processing program and note Span in the actual value field.

For variations <15% of the control value the increase (span) has to be setup again according the directions of the equipment manual.

For variations >15% of the control value the analyzer is not recalibrated, before identifying the reason for the variations (the transfer standards and the analyzer have to be checked).

111

46.2 Dilution system

Zero gas: Take the sampler tube off the test gas distributor and connect it to the dilution

system. Set the dilution system to "zero gas". After 3 cycles read the measured value in the data processing program and note Zero in the actual value field.

For variations <0,5µg/m³ the zero point has to be setup again according to the directions from the equipment manual. For variations >0,5µg/m³ the production of zero gas of the analyzer and of the transfer standard have to be checked.

Span gas Set the dilution system to "span gas". After 3 cycles read the measured value

in the data processing program and note Span in the actual value field.

For variations <15% of the control value the increase (span) has to be setup again according the directions of the equipment manual.

For variations >15% of the control value the analyzer is not recalibrated, before identifying the reason for the variations (the transfer standards and the analyzer have to be checked).

46.3 Permeation system

Zero gas: Take the sampler tube off the test gas distributor and connect it to the

permeation system. Set the permeation system to "zero gas". After 3 cycles read the measured value in the data processing program and note Zero in the actual value field.

For variations <0,5µg/m³ the zero point has to be setup again according to the directions from the equipment manual. For variations >0,5µg/m³ the production of zero gas of the analyzer and of the transfer standard have to be checked.

Span gas Set the permeation system to "span gas". After 3 cycles read the measured

value in the data processing program and note Span in the actual value field.

For variations <15% of the control value the increase (span) has to be setup again according the directions of the equipment manual.

For variations >15% of the control value the analyzer is not recalibrated, before identifying the reason for the variations (the transfer standards and the analyzer have to be checked).

46.4 Establishing the control value of the test gas for the functional control

When the calibration is closed, the sampler tube has to be reconnected to the sampler distributor. Operate the analyzer in the station and release the functional control. After the conclusion of the functional control the measured value of the span gas shall be introduced into the station computer as control value.

112

47 Evaluation and documentation

The calibration shall be recorded in the station logbook. The data transmitted in the measurement station will be transferred into an Excel spreadsheet for subsequent evaluation . The calibration form shall be stored in the calibration folder at the center of the

monitoring network. In case of conspicuous events during the calibration the manager of the monitoring

network shall be informed.

48 Quality Assurance Measures

The transfer standards are to be certified regularly in the calibration lab. The control value is standardised to 293 K and 101.1 kPa. The calibration certificate will be attached to the transfer standard. The maintenance of the control equipment and of the transfer standards shall be ensured through the monitoring network.

Execution of Repairs

Content

1 Scope, Field of Activity, Responsibilities 113

2 Resources and Technical Documents 113

3 Execution of Repair Works on the Analysers 113 3.1 On Site Diagnosis 113 3.2 Replacement of an Analyser 114 3.3 Repairs in the Repair Shop 114 3.4 Verification in the Calibration Lab 114

4 Execution of Repairs in the Field of Analysers 114

5 Chemicals 114

6 Quality Assurance Measures 115

113

49 Scope, Field of Activity, Responsibilities

This SOP applies to the analysis of errors and repairs of all equipment used in the air quality monitoring network. Repairs can be necessary upon notification from the air monitoring network centre and in the case of conspicuous features during the maintenance or calibration works. The repairs shall usually be carried out on site or in the own repair shop. In order to achieve the required data availability and quality, it is to be ensured that the repair works are carried out carefully and prompt. The functional capacity shall be ensured through a test. Responsible with the repairs is the head of the Level B monitoring network service. The final test of the analysers is subject to the calibration lab. The responsibility thereof belongs to the head of the calibration lab.

50 Resources and Technical Documents

For the execution of repair works the technicians shall be provided with all the manuals and with the appropriate tools. The provider of the monitoring stations has to hand out detailed documents for all the equipment used in the monitoring station. The often used spare parts and consumables are to be stocked, for example pump spare parts, filters, chemicals, o-rings, sealings.

51 Execution of Repair Works on the Analysers

Analysers that fail due to technical flaws in the air monitoring network or in the calibration lab, shall usually be repaired in the electronic repair shop. The measurements shall be continued during the repair period with backup equipment (if available). The necessity of repair can be activated through notifications from the monitoring network centre or through the problems arising during the maintenance or calibrations. Notifications could be for example:

Monitoring network service: problems arising during the monthly maintenance or calibration (perturbation, analyser cannot be set up, etc.).

Monitoring network centre: Not plausible measured values, erroneous 25 h function control, status signals

Calibration lab: Errors in the equipment of the calibration lab

51.1 On Site Diagnosis

Procedure for error search: Verification of equipment parameters Verification of the status indication of the analyser Previously it must be tried to make a reference of the notified error to a component, i.e.: Measured values zero, no low pressure: Vacuum pump out of order? The internal test functions of the equipment can be used according to the producer's instructions for the delimitation of the error, i.e.:

114

Electric test OK: Analytical error Not OK: Electronic error? Optical test OK: Pneumatics error Not OK: PMT/HVS? Should the tests on site lead to no results, the analyser has to be replaced and repaired in the repair shop.

51.2 Replacement of an Analyser

The replacement of analysers is to be executed as follows: The service technician writes the replacement with its date and serial number into station log book. The match of the replaced analyser with the station PC must be ensured. After the appropriate warm up phase the replaced analyser is to be calibrated. The replacement has to be communicated to the monitoring network centre and documented in the Equipment Replacement folder.

51.3 Repairs in the Repair Shop

In the repair shop the error is ascertained and the necessary repairing measures are to be taken. After successful repair a functioning test shall follow. The functioning test comprises two verifications

Execution of an analyser test on the basis of the repair protocol. Therefore the measured values specific for the equipment shall be tested, set up and recorded. In the repair protocols the necessary functions for the operation (i.e. supply voltage, flow rates) shall be checked, but also functions that due to longer experience have shown that if not working properly (i.e. thermostabilisation of a measuring cell) an error of the equipment is not immediately recognizable. Subsequently, the equipment shall be operated several days in measurement conditions.

51.4 Verification in the Calibration Lab

For the reintroduction into the monitoring network, the analyser is calibrated in the calibration lab and is subject to a lack of fit test. If the result is according to the criteria of the corresponding EN norm, it can be approved for use in the monitoring network. If not, the management of the monitoring network service shall take new repair measures.

The results of these tests shall be printed as results protocol and attached to the maintenance history folder. Therefore the calibration [component] template in force for the respective component shall be used.

52 Execution of Repairs in the Field of Analysers

Here are to be mentioned: air conditioning, doors and locks, fences, damage caused by vandalism, electric installation, meteorological transducers and compressors. For the appropriate specialised execution, the competent technician is in charge. If he cannot carry out the repair alone, the head of the monitoring network has to be informed, in order for him to be able to establish the subsequent course of action.

53 Chemicals

The safety data sheets for the used chemicals are to be stored in an accessible manner for the technicians.

115

Their disposal shall be done according to the disposal concept.

54 Quality Assurance Measures

For the execution of the repairs, a regular training shall be done by the producer, for example upon new equipment acquisition. A regular experience exchange of all the technicians has to take place.

Repairs protocol SO2 ML 9850 B SN: .........................

Software version .....................

Clean monitor .....................

Clean piping, magnet valves, filter case and measurement cell .....................

Check pressure and flow sensors .....................

Renew activated charcoal .....................

Check flow

Sample gas flow 869 ml .....................

Purge flow permeation 130 ml .....................

Purge flow kicker 2275 ml .....................

Zero gas flow purge flow permeation + purge flow kicker .....................

Density test (only test with low pressure) .....................

PMT check drying agent, renew .....................

Check UV lamp, adjust, renew >0,5Vpp und <2Vpp .....................

Record measured values:

Preprocessor pots .....................

Instrument Status .....................

System Temperatures .....................

Calibrate monitor (Background Cycle) and span gas .....................

Compile calibration protocol

Spare part Order no. SN, if available

116

Electric security check Insulation resistance [MOHM]: .............................

DIN 57 701 GUV 2.0 Protective conductor resistance [mOHM]: .......................

Perform monitor check Test passed yes / no .............................

Date: ........................... Signature: .......................................................

Change of Container Sites

Content

1 Appliance area, responsibilities ................................................................................. 117

2 Planning, permit procedure ........................................................................................ 117

3 Operations performed by the service department .................................................. 117

4 Quality assurance measurements ............................................................................ 118

5 Device maintenance, maintenance time .................................................................. 118

117

55 Appliance area, responsibilities

This method instruction is applied for the operations established in the service domain in station transfer of the air measuring network. The monitoring stations will be transferred with regularity depending on station type (street station, background station, ozone station or long term station). Transferring procedure has the following structure: Site research, permit procedure, application for electricity, phone, special utility, rehabilitation of the site Decommissioning, disassembly of devices, preparation operations for the station transport, maintenance of devices, station transfer, assembly of devices, start the station

56 Planning, permit procedure

Measurement domain and station type will be presented. Management representative intends to visit the selected measurement site together with a representative of the regional authority / underground engineering department and one representative of the competent police authority. Photos will be taken for the internal judgments. For the site selection will be considered the relevant specifications of the laws regarding the installation of a monitoring station. The application for special usage will be given to the regional authority / underground engineering department after internal selection of the new site. After the regional authority issues the permit, the application will be made for getting the digging allowance from the underground engineering department. A copy of it will be transmitted to the competent police department and tot the mandated firm for electrical installation. The application will be given to the electricity distributor for providing a low tension line. A map of the area 1:1000 (Arcview) will be attached to the application documentation. At the phone company will be given an application for a ISDN connection (together with a site plan). Before transferring the monitoring station, the Telecommunication firm and electrical installation firm will be announced upon the required time for switching off. After transferring, an external operator will be mandated with the rehabilitation of the site; after ending of the rehabilitation, a site control will be carried out. Electricity distributor and telecommunication distributor and the electricity installation firm will be informed about the moment of transferring the monitoring station by an external firm, so that the operations can be started. Depending on the site conditions, a firm will be mandated with a installation of a protection fence for the sampling. The site appearances will be documented according to the EU specifications.

57 Operations performed by the service department

Decommissioning: Decommissioning intention will be notified at the service group. After this moment the competent service technician has to shut down the station at the next possible moment. Before switching off, the service technician has to be assured that the quality assurance of a final calibration has been performed and all the data can be accessed from the central office.

118

All the mobile devices will be disassembled and sent to the service workshop. The device assembly and disassembly will be always by two technicians performed.

Assembly of the sampling tubes for particles and gaseous components. Roof operations will be sealed against water.

Depending on water producer, the roof hood should be removed so that the crane eyes can be reached. Fasteners of the fundament have to be released.

Technician has to assure himself 2 days before moving time that all the operations (electricity, telecommunication connections and fence are removed from the old site) were duly carried out and the station can be moved away. Moving the station: technician has to assure himself at the moment of the about the access of the old and new site at least 1 hour before the transfer moment. The transfer will be performed by an external firm and will be accompanied by the technician. Maintenance of devices: devices and sampling tubes/hoses have to be cleaned and checked. Wear parts will be renewed if necessary. Monitors will be checked automatically (SO2, NOx, CO, O3) or a check will be performed in the device checking space (dust, soot, benzene). This step is described in the VA "Carrying out the reparations ". Checking documents will be inserted in the CV facts and the devices will be prepared for the reinstallation. Installation of station in maintenance plan, documentation: Modifications of maintenance plan will be performed. Device assembly will be also for the station identified by the dissemble data. After the new station has been installed, new devices with new site names and installation data will be put in the table ―Assembly‖. All the sites and device assembly are reproducible. Month of annual maintenance is always the month of starting the work. Installation of the devices, beginning the work: if the energy supply is available it can be began with the installation of devices. All the operations will be performed that are according to the annual maintenance (maintenance plan). On the measuring data computer the station number of the new site will be introduced and saved. The monitoring data of the old site will be removed from the hard disk. Monitors will be set up with transfer standards and the target values will be entered in the calibration parameter sheet of the monitoring data program. Monitoring value corrections for escalation will be turned off. Station will be declared as ready to work.

58 Quality assurance measurements

Final calibration before turning off the monitoring station at the old site Checking monitors after reconditioning Setting up the monitors with certified transfer standards Calibration of start up after the notification of the start-up readiness

59 Device maintenance, maintenance time

After start working all needed maintenance and reparation operations have to be carried out.

119

Change of measurement location of a Monitoring Vehicle

Inhaltsverzeichnis

1. Ziel und Zweck ................................................................................................... 120

2. Geltungsbereich ................................................................................................. 120

3. Technische Umsetzung ....................................................................................... 120

3.1. Geräteausstattung Messfahrzeug 120

3.2. Herstellung der Messbereitschaft am vorgesehenen Messstandort 120 3.2.1. Meteorologische Messungen 121

3.3. Aufhebung der Messbereitschaft und Umsetzung des Messfahrzeugs 121

120

1. Ziel und Zweck

Diese Arbeitsanweisung definiert die notwendigen Arbeitsabläufe zur Herstellung und

Beendigung der Messbereitschaft des Luftmessfahrzeugs im Rahmen von Messprojekten.

2. Geltungsbereich

Die Arbeitsanweisung gilt für sämtliche Einsätze des Luftmessfahrzeugs im Rahmen der

Durchführung von bestätigten Messprojekten.

3. Technische Umsetzung

3.1. Geräteausstattung Messfahrzeug

Die jeweils aktuelle Geräteausstattung des Messfahrzeuges ist der Gerätedatenbank zu

entnehmen.

3.2. Herstellung der Messbereitschaft am vorgesehenen Messstandort

Zur Herstellung der Messbereitschaft am vorgesehenen Standort sind die nachfolgend, in

chronologischer Reihenfolge beschriebenen Arbeitsschritte abzuarbeiten:

1. Positionierung des Messfahrzeugs und ggf. Ausgleich von Bodenunebenheiten.

2. Sicherung des Messfahrzeuges gegen unbeabsichtigtes Wegrollen.

3. Anschluss der Energieversorgung und Sicherung der Anschlüsse am Fahrzeug, dabei

auf sichere Verlegung der Anschlusskabel im Gelände und korrekte Schalterstellung

für Versorgungsstrom achten.

4. Stromzählerstand notieren.

5. Stromversorgung der Klimaanlage auf „Netz― umschalten.

6. Besonderheiten bei Akkubetrieb: Bei fehlender externer Stromversorgung sind

sämtliche, für den Messeinsatz nicht notwendige Verbraucher auszuschalten. Da der

Hochvolumensammler bei Akkubetrieb keine Stromversorgung hat, ist auch das

entsprechende Ansaugsystem nicht zu installieren. Die Klimaanlage ist in

Abhängigkeit der Außentemperatur einzuschalten, gegebenenfalls aus

Energiespargründen mit einer höheren Raumtemperatur (max. 30°C) zu betreiben.

7. Ausfahren des Messmastes für meteorologische Messungen (siehe 3.2.1.).

8. Ausfahren bzw. Montage aller Ansaugsysteme (Probenahmeköpfe) auf dem

Fahrzeugdach.

9. Prüfung der Ausrichtung des Fahrzeugs mittels Kompass (Voraussetzung für korrekte

Ermittlung der Windrichtung). Kontrolle der Anzeige für „Richtung― im Programm

auf dem Stations-PC; sollte die Richtung einen anderen Wert als den mit Kompass

ermittelten Wert haben, war die Ermittelung mittels Navigationssystem nicht

erfolgreich und muss manuell mit dem Kompasswert korrigiert werden.

10. Prüfung der Datenanbindung.

11. Einlegen der Filter in den Hochvolumensammler und Parametrierung.

- Änderung des Stationsnamens, wenn notwendig, im Stations-PC. Diese

Änderungen sind in Absprache mit dem Leiter der Messnetzzentrale

durchzuführen.

121

12. Start der Datenerfassung und Beginn der Messungen.

13. Kontrolle der Datenübertragung (Abruf durch die Messnetzzentrale).

14. Durchführung einer Funktionskontrolle für alle Analysatoren.

15. Monitor des Navigationssystems abnehmen und sicher verstauen.

16. Herstellung der Sicherheit des Fahrzeugs (komplettes Fahrzeug auf Verschluss

prüfen).

Eine notwendige Kalibrierung der Analysatoren sowie des Hochvolumensammlers ist vor

Beginn der Messungen vom Kalibrierlabor durchzuführen.

3.2.1. Meteorologische Messungen

Am vorgesehenen Standort muss die Möglichkeit zum vollständigen Ausfahren des

Messmastes gegeben sein. Die mit der Überführung des Fahrzeugs und der Herstellung der

Messbereitschaft beauftragten Servicetechniker haben sich vor Aufstellung des

Messfahrzeugs am ausgewählten Standort davon zu überzeugen, dass der Messmast

gefahrlos und ohne Behinderungen ausgefahren werden kann.

Die wichtigste Voraussetzung für eine korrekte Erfassung der Windrichtung ist der Betrieb

des Navigationssystems während der Überführung des Fahrzeugs. Anhand der Positions-

bzw. Lagebestimmung des Navigationssystems erfolgt die Einnordung der Windmessung.

Die korrekte Ausrichtung des Fahrzeuges ist mittels Kompass zu überprüfen.

3.3. Aufhebung der Messbereitschaft und Umsetzung des Messfahrzeugs

Für die Aufhebung der Messbereitschaft bzw. die Herstellung der Transportbereitschaft sind

die nachfolgend in chronologischer Reihenfolge beschriebenen Arbeitsschritte abzuarbeiten:

1. Beendigung der Datenerfassung und damit Beendigung der regulären Messungen.

2. Einfahren des Messmastes für meteorologische Messungen (Wichtig: Kontrolle, ob

Mast komplett eingefahren ist!). Kompressor ausschalten!

3. Einfahren des Probenahmesystems sowie der Ansaugsysteme der Staubmessgeräte,

Demontage des Ansaugsystems des Hochvolumensammlers, Demontage der

Vorabscheider (Probenahmeköpfe) auf dem Fahrzeugdach. Die Staubmessgeräte sind

bis zum Anschlag in die Racks zu schieben und festzuschrauben.

4. Stromversorgung der Klimaanlage auf „Batterie― umschalten.

5. Demontage der Energieversorgungsleitungen und Sicherung der Anschlüsse am

Fahrzeug, dabei auf sicheres Verstauen der Anschlusskabel achten.

6. Stromzählerstand notieren.

7. Sicherung beweglicher Gegenstände im Kofferaufbau (Messraum) des Fahrzeugs

(insbesondere Drehstuhl und Leiter).

8. Einschieben und Arretierung der Einstiegsleiter, Kontrolle auf sichere Befestigung.

9. Kontrolle der Betriebsbereitschaft des Fahrzeugs:

o optische Luftdruckkontrolle der Bereifung,

o Ölstand Motor prüfen über FDS/FIS (Fahrzeug-Diagnose/Informations-System,

siehe Fahrzeughandbuch).

10. Monitor des Navigationssystems installieren.

11. Umsetzung des Fahrzeugs.

122

Calibration Laboratory

Content

1 Scope, field of activity, measurement procedure, control procedure features, responsibilities 123

2 Chemicals and devices 123

3 Performing of tasks 124 3.1 Lab reference standard NOx 124 3.2 Lab reference standard SO2 124 3.3 Lab reference standard O3 124 3.4 Lab reference standard CO 124 3.5 Lab reference standard BTX 124 3.6 Certification of mobile transfer standards 124

4 Gravimetric determination of PM10 concentration 125

5 Quality assurance measures 125 5.1 Standard traceability to national standards 125 5.2 Participation in interlaboratory tests 125

6 Measurement uncertainty 125

7 Device maintenance, maintenance intervals 125

8 Annex: Calibration labs 126 8.1 Traceability of air quality data 126 8.2 Linearity test 126 8.3 Receiving inspection 126 8.4 Type approval test for suitability evaluation on site 127 8.5 Reference standards for physical measures 127 8.6 Gravimetric analysis 128

123

60 Scope, field of activity, measurement procedure, control procedure features, responsibilities

This PI is valid for all work sequences, which have to be performed in the calibration lab. The calibration lab provides the laboratory reference standards for the components NOx, SO2, O3, CO and BTX. For the calibration of thermo sensors, pressure sensors and flow sensors, reference measurement devices shall be kept ready. For the calibration of the balances, the certified reference weights listed in the balance manuals must be available. The reference measuring procedure (conditioning, weighing, calculation) for particulate matter is performed in the calibration lab. The traceability of the gas standards is ascribed to the National Reference Lab. The basic calibration and function check of new or repaired analysers is performed in the calibration lab (linearity). The calibration lab participates in comparison measurements on National Level (Level A). The calibration lab certifies the transfer standards used in the air quality monitoring network in determined cycles. This certification is stipulated to take place quarterly, but it is recommendable to verify the transfer standards in the calibration lab each time before they are used. The measurement uncertainty of the measured values is to be determined by the calibration lab. The control procedure features are indicated in the corresponding EN standards. The head of the calibration lab is the one responsible for all these operations.

61 Chemicals and devices

Reference-Analysers NOx, SO2, O3, CO, BTX Lab reference gas standards NO Dilution system NO2 Permeation system SO2 Permeation system O3 UV-standard with generator

BTX Permeation (3/1 chamber kiln with 1 permeation tubule)

Multi-component gas mixing unit with NO, NO2, SO2, O3, CO, BTX, automatic control system H2O Data collection As in monitoring network station Mobile transfer standards NOx Dilution with GPT (converter) SO2 Permeation / dilution O3 Calibratable O3 generator CO Dilution / gas bottle BTX Permeation Reference measuring devices Barometer Thermometer Flow measurement devices for different

measurement fields

124

Reference weights Adapted to the balance(s) Balance room according to EN12341 PC for documentation, interpretation, planning

62 Performing of tasks

The following operations are described exactly in the corresponding SOPs.

62.1 Lab reference standard NOx

The NO2 standard is determined by means of gravimetric analysis and volume determination (ISO 6145-10). The NOx channel of the reference analyser is set with the calculated concentration. The dilution system is used for the automatic function control.

62.2 Lab reference standard SO2

The SO2 standard is determined by means of gravimetric analysis and volume determination (ISO 6145-10). The SO2 channel of the reference analyser is set with the calculated concentration. The permeation system is used for the automatic function control

62.3 Lab reference standard O3

The O3 standard is determined by means of UV-standard (without scrubber, concentration calculation according to Lambert-Beer). Subsequently, the O3

reference analyser is calibrated with the known ozone concentration.

62.4 Lab reference standard CO

The CO standard is transferred to the reference analyser by means of gas bottles certified by the National Reference Lab. For backup, two gas bottles are available for each concentration respectively. The permeation system is used for automatic function control.

62.5 Lab reference standard BTX

The BTX (Benzene, Toluene, Xylene) standard is determined by means of gravimetric analysis and volume determination (ISO 6145-10). The response factors of the reference analyser are determined with the calculated concentration. The permeation system is used for the automatic function control.

62.6 Certification of mobile transfer standards

All mobile transfer standards have to be certified every 6 months according to EN-Standards. It is recommended to perform this verification more often. To this purpose, the transfer standards are brought from the monitoring network service to the calibration lab and are connected to the reference analyzer. The usual concentration of the transfer standard is set. After the running-in time, the concentration is certified and is documented in the folder Testing Agents.

125

63 Gravimetric determination of PM10 concentration

The gravimetric determination of PM10 concentration must be performed according to the stipulations in the EN12341. Special attention is to be paid to following elements: Dabei ist besonders zu beachten: Filter material Quartz Conditioning 48h, 20 + 1°C, 50 + 5% RF Storage in dedicated transport containers Labelling of filters, order Lab system In the case of collection devices, the volume is to be determined and calibrated. The temperature and pressure sensors are to be calibrated according to the instruction of the producer. The PM10 head is to be cleaned and greased monthly.

64 Quality assurance measures

64.1 Standard traceability to national standards

The gas standard is to be traced back to the National Gas Standard in the calibration lab in determined cycles. For this, it is necessary that transfer standards are certified regularly in the National Reference Lab. The reference measurement devices of the National Reference Lab have to be certified regularly (usually once a year) by the National Metrological Institute.

64.2 Participation in interlaboratory tests

In addition, the participation of regional calibration labs in interlaboratory tests on a national level is required. For the participation, an analyser, the corresponding transfer standard and a data collection is necessary for each component. The measurement values determined this way reflect the mastery of the measurement procedure. The result report from the NRL is to be documented in the interlaboratory test folder and to be commented in case of deviations.

65 Measurement uncertainty

For the lab reference standards and transfer standards, the extended measurement uncertainty (see SOP determination of extended measurement uncertainty) is to be indicated. The measurement uncertainty must not be higher than the value indicated in the corresponding standard. In the future, the determination of measurement uncertainty will be performed by the calibration lab. The calculation shall be based upon the calculation specifications of the corresponding EN standard.

66 Device maintenance, maintenance intervals

The devices in the calibration lab are checked by the monitoring network service and are subjected to the same rules as monitoring network devices.

126

67 Annex: Calibration labs

67.1 Traceability of air quality data

The tasks of the Level B calibration labs (CL) are diverse. One of the main tasks is the supply of traceable transfer standards for the calibration of measurement devices in the monitoring networks. Traceable means, that these transfer standards are connected to national/international standards by an uninterrupted string of comparison measurements with known measurement uncertainty. National standards shall be kept by the National Reference Laboratory (NRL) and shall be linked to international standards by means of international comparison measurements in the framework of the BIMP. The laboratory reference standards used in the calibration labs as a basis for calibration have to be certified by the NRL by means of comparison measurements with the national standards. The uncertainty of the certified test gas concentration shall always be indicated in this process. Both test gases in test gas bottles and test gas generators can be used as laboratory reference standards. The stability of the laboratory reference standards used must be monitored constantly by the Reference Calibration Labs by means of appropriate measures (e.g. cross-checks with a second standard or independent procedures) The calibration labs perform comparison measurements of the transfer standards with the laboratory reference standards and determine their uncertainty. To this purpose, reference measurement devices are used, which have been previously calibrated with the laboratory reference standards. Then, the transfer standards are deployed in the monitoring stations for the calibration of measurement devices. Thus, the traceability of air quality data to national standards is guaranteed. Additional to reference standards, the CL‘s also have other standards at their disposal (laboratory work standards), which can be used, for example for the daily zero/span control of the reference measurement devices and for the linearity test of measurement devices.

67.2 Linearity test

The linearity of measurement devices is to be tested regularly, yearly or every three years, according to test results. Also, after repairs or basic maintenance works on measurement devices, a new linearity test shall be necessary. With newly procured measurement devices the linearity test shall take place in the CL before its installation in a monitoring station.

67.3 Receiving inspection

The EN ISO/IEC 17025 „General requirements for the competence of testing and calibration laboratories― require that newly acquired measurement devices are tested for the observance of technical specifications and for compliance with the requirements of that particular measurement procedure. These receiving inspections shall take place in the CL. The receiving inspection for new measurement devices comprises a formal part, in which the completeness of delivery is checked and a practical part, in which data transfer, device parametrisation and the compliance with special performance characteristics are checked. The basic calibration and the first linearity test shall also take place in the framework of the receiving inspection. Only if the measurement device fulfils all requirements it may be cleared for measurement use. The results of the inspection and the approval of measurement devices are to be documented.

127

The following scheme shall again make clear the tasks described above:

National Standards

(NRL)

Laboratory Reference

StandardsTransfer Standards

Laboratory Working

Standards

Reference Analyser

Analyser

co

mp

ari

son

measu

rem

en

ts

calib

rati

on

calibration

init

ial ch

ecks

Lack o

f F

it c

heck

measurement

zero

/span

check

certification

cert

ific

ati

on

bas

ic c

alib

rati

on

67.4 Type approval test for suitability evaluation on site

The European standards for the measurement procedures for SO2, NO/NO2, O3 and CO require that before use a measurement device be tested for its suitability to fulfill the requirements of EU Directives regarding data quality even in the specific conditions of the envisaged measurement site. For this, the measurement uncertainty of the measurement device is calculated taking into consideration the results of the type approval test and the specific conditions of the measurement site and then compared with the requirements regarding measurement uncertainty of the EU Directives. The task of performing the type approval test for suitability evaluation shall be fulfilled in the LC‘s. A close collaboration between calibration lab, monitoring network service and monitoring network centre shall be necessary in order to determine the starting values required for the calculation of measurement uncertainty. All calculations shall be documented.

67.5 Reference standards for physical measures

In the monitoring network service volume flows, from PM10 samplers for instance, as well as pressure and temperature sensors have to be verified regularly. The balances used for the gravimetric determination of PM10 shall be calibrated regularly with reference weights. The CL‘s must have at their disposal calibratable reference measurement devices and certified reference weights for the measures volume flow, pressure, temperature and mass and must organise and ensure their regular recalibration or metrological verification by the NMI.

128

These reference measurement devices shall be used in order to calibrate the measurement devices used for the tests in the stations and the balances.

67.6 Gravimetric analysis

The CL‘s are responsible for the gravimetric determination of PM10 and PM2,5. For this, they have air conditioned balance rooms for filter conditioning and weighing. The course of action and the requirements for the gravimetric determination of PM10 and PM2,5 are described in the corresponding European standards (EN 12341 and EN 14907).

Receiving inspection, basic calibration, linearity test and type approval test

for suitability evaluation of measurement devices

Content:

1. Purpose ............................................................................................................... 129

2. Scope ................................................................................................................... 129

3. Responsibilities .................................................................................................. 129

4. Procedure description ....................................................................................... 129 4.1. Receiving inspection ..................................................................................... 130 4.2. Basic calibration ............................................................................................ 130 4.3. Linearity test .................................................................................................. 130 4.4. Type approval test for suitability evaluation on site ....................................... 131 4.5. Determination of performance indicators ....................................................... 131 4.6. Release of measurement devices ................................................................. 133

5. Documentation ................................................................................................... 133

6. Also applicable documents ............................................................................... 133

129

1. Purpose

These PI describe the course of action and responsibilities during receiving inspection, basic

calibration, linearity test and type approval test for suitability evaluation of measurement

devices. These PI ensure that:

New measurement devices are tested for their conformance with technical

specifications and with requirements of the European standards

Only those measurement devices are cleared for use, that fulfil these requirements and

The data quality requirements of the EU Directives are observed under the specific

conditions from the measurement location

2. Scope

These PI are valid for the regional calibration labs and are to be applied to all newly procured

measurement devices.

3. Responsibilities

Activity Responsible Contributing Information

Verification of

delivery

completeness

Chief of calibration

lab

Technician

Verification of device

parameters and data

transfer

Assigned technician Chief of calibration

lab

Basic calibration Assigned technician Chief of calibration

lab

Linearity test Assigned technician Chief of calibration

lab

Calculation of

performance

indicators

Assigned technician Chief of calibration

lab

Suitability evaluation

for the use in a

concrete location

Chief of calibration

lab

Network service

Network centre

Head of monitoring

network service

Release or blocking

of measurement

devices

Chief of calibration

lab

4. Procedure description

The procedure comprises a formal receiving inspection of new measurement devices, the

basic calibration of the measurement device, the linearity test and the type approval test for

suitability evaluation for the use in a concrete location.

130

Under certain conditions additional performance indicators will have to be determined.

4.1. Receiving inspection

Before acceptance, newly procured measurement devices are to be tested for their conformity

with the requirements of technical specifications. This verification comprises at least:

1. control of completeness of delivery (e.g. installed optional equipment, associated spare

parts and consumables, operating instructions, maintenance manual and other device

documents)

2. verification and documentation of device parameterisation if the device is tested for

suitability according to European standards, then the parameterisation of the device

must correspond to that indicated in the test report

3. Verification of data transfer between measurement device and data acquisition system:

interface protocol if specified, transmission of function and error signals, conformity

with other requirements related to data transfer and remote control of the devices

4. Verification of specified performance parameters: this verification can be dispensed

with if the producer hands in a testing protocol for every device, from which the

fulfilment of required performance parameters is clear.

If no performance indicators have been specified for the measurement device and

the producer has not handed in any testing protocol, then at least the following

performance indicators are to be determined in the subsequent course of action:

Response time (rise and fall)

Lower detection limit or repeatability standard deviation at point zero

Repeatability standard deviation at span level

The verification of delivery completeness according to point 1 has to be performed by the

chief of the calibration lab. A technician will be assigned for the rest of the verifications.

All verifications shall be documented in the device file of the measurement device.

4.2. Basic calibration

The basic calibration is performed using a laboratory reference standard as two-point

calibration at zero and at a test gas concentration of approx. 70-80% of the certification range.

In the case of NO/NO2 measurement devices, the converter efficiency is to be determined

before calibration. As it is a new device, the converter efficiency must be ≥98 %. The basic

calibration and the converter test are to be documented in the device file of the measurement

device.

4.3. Linearity test

Before the release of a measurement device for the use in the monitoring stations, a linearity

test shall be performed.

The linearity of a measurement device is to be tested in the range of 0 to 95% of the

certification range. For this, 5 test gases shall be used, which correspond to approx. 20%,

40%, 60%, 80% and 95% of the certification range of the measurement device and zero gas in

the order 80% 40% 0% 60% 20% 95%. The measurement cycle shall be

repeated at least 5 times.

131

From this data the regression coefficients and the (relative) residuals are calculated.

Starting from the maximal value of the residuals, the interval for repeating the linearity test is

set:

Maximal value of residuals ≤ 2% repeat linearity test after

3 years

Maximal value of residuals >2% and ≤ 6% repeat linearity test after 1 year

Maximal value of residuals > 6% the measuremend device

cannot be

cleared for measurement use.

The deviation from the regression coefficients may not exceed 5 ppb (0,2 ppm for CO) at zero

concentration.

The results of the linearity test must be documented in the device file.

4.4. Type approval test for suitability evaluation on site Before the initial installation of the measurement device in a monitoring station, its suitability under the specific conditions from the location shall be evaluated. For this, the measurement uncertainty shall be calculated using the results of the suitability test and taking into consideration the site-specific conditions and then it shall be compared with the requirements of the corresponding EU Directive.

The following site-specific conditions shall be taken into consideration for the calculation of the measurement uncertainty:

- Modification of sample gas pressure

- Modification of sample gas temperature

- Modification of surrounding temperature

- Voltage fluctuations

- Modification of sample gas humidity

- Concentration ranges of compounds with cross sensitivity

- Uncertainty of test gases used for calibration

- Calibration frequency

For the determination of site-specific conditions, a close collaboration between monitoring network service, data centre and calibration lab is necessary. The site-specific starting values for the calculation of measurement uncertainty are to be obtained by the monitoring network service and the data centre and are to be delivered to the chief of the calibration lab.

The chief of the calibration lab calculates the measurement uncertainty according to the requirements of the European standards and decides upon the release of the measurement device for use in the designated station.

All calculations shall be documented.

4.5. Determination of performance indicators

The following performance indicators must be known for all measurement devices:

Response times

Lower detection limit or repeatability standard deviation at zero

Repeatability standard deviation at span level

If these indicators are not available in the testing protocols of the producer, then they have to

be determined.

132

The determination of these indicators is to be performed according to the requirements of the

European standards for the respective measurement procedures.

The indicators shall be verified according to European standards to see whether they fulfil the

minimum requirements. Only if the minimum requirements are fulfilled can a measurement

device be released for measurement use.

133

4.6. Release of measurement devices

After completion of the verifications, the chief of the calibration lab decides upon the release

for measurement use of these measurement devices, according to the results of the tests.

The release shall be documented in the device file.

Additionally, each measurement device shall be labelled with a sticker on which the release

and the date of the next linearity test are mentioned.

If a measurement device has not been released on grounds of the test results, then it is to be

labelled as ―blocked for use‖

5. Documentation

All verifications are to be documented in the device file of the measurement device.

6. Also applicable documents EN 14211 „Standard method for the measurement of the concentration of nitrogen

dioxide and nitrogen monoxide by chemiluminescence―

EN 14212 „Standard method for the measurement of the concentration of sulphur

dioxide by ultraviolet fluorescence―

EN 14625 „Standard method for the measurement of the concentration of ozone by

ultraviolet photometry―

EN 14626 „Standard method for the measurement of the concentration of carbon

monoxide by nondispersive infrared spectroscopy―

EN 14 662 „Standard method for the measurement of benzene concentration‖

-

Certification of Test Gases

Content

1. Purpose ............................................................................................................ 135

2. Scope ............................................................................................................... 135

3. Terms and abbreviations ................................................................................ 135

4. Responsibilities............................................................................................... 135

5. Procedure description .................................................................................... 135 5.1. Certification of laboratory reference standards .......................................... 136

5.1.1. Monitoring of laboratory reference standard stability ............................. 136 5.1.2. Subsequent measurements ................................................................... 137

134

5.2. Certification of transfer standards .............................................................. 137 5.3. Uncertainty of test gas concentrations ...................................................... 139 5.4. Documentation .......................................................................................... 139

135

1. Purpose

These procedure instructions describe the courses of action and responsibilities during the

certification of test gases. By these PI, it is to be ensured that:

Transfer standards traceable to national standards are available for the calibration of

measurement devices and that

The uncertainty of the test gases used for calibrations is determined.

2. Scope

These PI are valid for the regional calibration laboratories…. They shall be used for all newly

procured measurement devices.

3. Terms and abbreviations

Traceability: A measurement result can be called traceable if it is connected

by an uninterrupted string of comparison measurements with

specified measurement uncertainties to a suitable reference

standard, generally to an international or national reference

standard.

Laboratory reference standards:

Test gases calibrated by the National Reference Laboratory

(NRL) or calibrators with a specified uncertainty.

Transfer standards: Test gases certified by a regional calibration lab by comparison

with a laboratory reference standard for the calibration of

measurement devices in the stations.

4. Responsibilities

Activity Responsible Contributing Information

Test gas procurement Chief of

calibration lab

Organisation of reference

standard certification

Chief of

calibration lab

Execution of comparison

measurements

assigned

technician

Certificate release Chief of

calibration lab

5. Procedure description

136

One of the main tasks of the calibration lab is to ensure that the air quality data acquired from

the network is traceable to national/international standards and are therefore comparable on an

international level.

For the fulfilling of this task, a series of steps is necessary. The following scheme illustrates

the general course of action.

The laboratory reference standards used in the calibration labs are to be certified by

comparison measurements with national standards. Thus, the laboratory reference standards

of the calibration lab are traceable to the national standards. Performing the comparison

measurements is the task of the National Reference Laboratory (NRL)

Transfer standards are certified by means of comparison measurements with the laboratory

reference standards. Thus, transfer standards are also traceable to national standards.

Subsequently, the certified transfer standards are used to calibrate the measurement devices in

the stations. By means of this string it is ensured that the air quality data obtained in the

stations with the measurement devices are traceable to national standards and thus comparable

on an international level.

5.1. Certification of laboratory reference standards

The chief of the calibration lab is responsible for the organisation of regular laboratory

reference standard certifications by the National Reference Laboratory. He organises the

acquisition of necessary test gases and closes the necessary agreements with the NRL for the

execution of certifications.

Test gases in pressure gas bottles which are to be used as laboratory reference standards shall

always be certified together with the associated pressure reducer. The pressure gas bottle and

the pressure reducer are to be viewed as a unit and the pressure reducers used are to be

marked accordingly.

Test gas generators (e.g. for ozone test gas), that are to be used as a laboratory reference

standard, have to be certified yearly by the NRL.

5.1.1. Monitoring of laboratory reference standard stability

The laboratory reference standards are the basis for all calibrations in the monitoring network.

Therefore, it must be ensured that deviations from the certified concentrations are

immediately noticed and that the appropriate measures are initiated.

The chief of the calibration lab shall draft a test plan and shall ensure that all necessary tests

are performed regularly.

National

standards

(NRL)

Laboratory

reference

standards

Comparison

measurement

Measurement

devices in the

stations

Transfer

standards Comparison

measurement

Calibration

137

The stability of test gases in pressure gas bottles is to be verified monthly by means of cross

comparison with a second certified test gas bottle. The deviation from the certified

concentration may not exceed 1%. Should the deviations determined be higher, then the test

gases in question shall be certified anew or new test gases shall be procured, that shall be

subsequently certified.

The stability of ozone test gas generators is to be verified by means of comparison

measurement with direct UV-photometry. The maximal allowed deviation of the measured

value from the certified value is 1%. Should the deviation be higher, then a new certification

by the NRL shall be organised.

5.1.2. Subsequent measurements

When new test gases for the use as laboratory reference standards are procured, it is not

always necessary to have them certified by the NRL. The calibration lab can perform its own

subsequent measurements, by comparing the new test gases with the ones used until then as

reference standards. The uncertainty of the reference standards shall be calculated anew.

It is to be noted, that with every subsequent measurement the uncertainty of the laboratory

reference standard rises. This also affects the uncertainty of the transfer standard

concentrations.

The uncertainty of the transfer standards used for the calibration of measurement devices

directly influences the uncertainty of air quality data. Therefore, it must always be verified if

the uncertainty of transfer standards is low enough to respect the allowed uncertainty of air

quality data.

5.2. Certification of transfer standards

Transfer standards are certified by means of comparison measurements with the laboratory

reference standards.

For this, the reference measurement devices are calibrated with the laboratory reference

standards. Then the concentration of transfer standards is determined with these devices.

Additional to the determination of the transfer standard concentration the uncertainty of the

test gas concentration is to be calculated.

Test gases in pressure gas bottles are to be certified before their first use. The pressure reducer

shall always be included in the test. The test gas bottle and the pressure reducer are to be

viewed as a unit. The pressure reducer shall be marked accordingly.

For test gases from pressure gas bottles the testing certificate is valid until the expiration of

the stability guarantee of the producer. Intermediate tests are recommended, as inappropriate

handling or storage of the test gas bottles can lead to premature concentration modifications.

Test gas generators are to be certified monthly and additionally after maintenance works or

repairs.

After the comparison measurements and the uncertainty calculations are concluded, a testing

certificate is to be compiled. The testing certificate has to contain the following:

A clear identification of the transfer standard (e.g. bottle number or ID-number of the

test gas generator)

The component

138

Date of certification

The determined test gas concentration

Expanded relative uncertainty of the test gas concentration (p=0,95)

Name of employee who has performed the certification

Date, until the certificate is valid.

Release by the chief of the calibration lab (signature/date)

139

5.3. Uncertainty of test gas concentrations

The uncertainty of laboratory reference standards is determined by the NRL and indicated on

the testing certificate.

The uncertainty of test gas concentrations of the transfer standards is to be determined by the

calibration lab. The following elements contributing to uncertainty are to be considered in the

process:

Uncertainty of the test gas concentration of the laboratory reference standard in

question

Uncertainty of the reference measurement device

The total uncertainty of the test gas concentration of the transfer standard is to be calculated

according to the rule of uncertainty propagation.

5.4. Documentation

For the registration of comparison measurement raw data for the certification of transfer

standards, the corresponding forms are to be used. The storage of filled in forms shall take

place in the calibration lab (the storage place must be specified).

The certificates of the NRL for test gas bottles that are to be used as laboratory reference

standards, are to be stored in the folder.

The certificates for test gas generators are to be stored in the respective device file. The

storage period for test gas bottle certificates and for raw data for transfer standard certification

is of at least 3 years.

Certificate (Concentration determination of transfer standards)

LOGO

ID-Number of standard:

Test gas:

Concentration:

Expanded uncertainty (p=0,95) :

certified on: by

This certificate is valid until:

Test leader

140

Certification of Test Gas Cylinders

Content

1. Purpose 141

2. Scope 141

3. Devices and accessories 141

4. Execution 141

5. Documentation 143

141

7. Purpose

This SOP describes the course of action in the test gas cylinder certification by means of

comparison measurement with a traceable reference standard.

8. Scope

This SOP is to be used in the calibration lab for the certification of test gases from pressure

gas cylinders with concentrations within the range indicated in table 1.

Component Concentration range

NO 0 -1200 µg/m³ 0 - 962 ppb

NO2 0 - 500 µg/m³ 0 - 261 ppb

SO2 0 – 1000 µg/m³ 0 – 376 ppb

CO 0 – 100 mg/m³ 0 – 86 ppm

Benzol 0 – 100 µg/m³ 0 – 30 ppb

Table 1: Concentration ranges for certification

9. Devices and accessories

Reference measurement device calibrated reference measurement device for the

determination of concentration of the gas to be

certified

Data acquisition for the collection of measurement data for the

certification

Gas pipes out of PFA, conditioned for the corresponding

measurement component for the connection of the

transfer standard to the reference measurement

device

Pressure reducer for the test gas only for the certification of test gas cylinders

T-piece for the branching off of test gas surplus (at test gas

cylinders)

Rotameter for the control of bypass flow ( 0-2 l/min )

Table 2: Devices and accessories for certification of test gas cylinders

10. Execution

The certification of test gases will occur by means of comparison measurements with the

corresponding laboratory reference standard. The following actions will be taken:

1. Verification of reference measurement device calibration

142

Over plug zero gas and the corresponding laboratory reference standard to

the reference measurement device, if necessary readjust the measurement

device.

2. Preparation of test gas cylinder

Install the associated pressure reducer

Install the gas pipes and the T-piece on the pressure reducer. The T-piece

shall be installed in such a manner so that it is later positioned immediately

near the sample gas inlet of the measurement device.

Vent the pressure reducer by means of water hammer ventilation. The

ventilation should be performed at least five times.

Open test gas cylinder and set an initial pressure of approximately 2 bar by

means of the reducing valve. Then open outlet valve cautiously and set a gas

flow of approx. 2 l/min.

While test gas is flowing, connect the test gas pipe at the sample gas inlet of

the reference measurement device.

Measure the bypass flow with the rotameter and set to a value between 0,2

and 0,5 l/min by means of the outlet valve of the pressure reducer.

3. Measurement of test gas concentration

Wait for a sufficient running-in time (at least the equivalent of 4 response

times) and record the measured values of the following 5 minutes.

Calculate the average and record in the measurement protocol as CPG.

Close the test gas cylinder in the following order: outlet valve cylinder

valve. Please note: By doing this, the pressure reducer will remain under

pressure which will largely prevent air from penetrating, so that no new

water hammer ventilation has to be performed before each use. As long as

the cylinder is used as transfer standard, the pressure reducer shall not be

uninstalled.

4. Calculation of test gas uncertainty

The total uncertainty of the test gas results from the uncertainty of the

laboratory reference standard used to calibrate the reference measurement

device and from the repeatability standard deviation of the reference

measurement device for a 5-minute average value.

m

rRSLPG

t

suu

22

uPG - relative

uncertainty of the certified test gas concentration

uL-RS - relative

uncertainty of the laboratory reference standard.

sr - relative repeatability standard deviation of the reference measurement

device at span level.

tm - number of individual measurements in 5 minutes with

2300

fr

m

ttt

tr - rise of the reference measurement device

143

tf - fall of the reference measurement device

Example: relative expanded uncertainty of

the laboratory reference standard

UL-RS = 3%

Relative repeatability standard deviation of the reference measurement device

sr = 1%

Response time (rise) of the reference measurement device ta = 57 s

Response time (fall) of the reference measurement device tf = 58 s

The simple relative uncertainty of the laboratory reference standard

uL-RS =UL-RS/2 is consequently 1,5 %.

The number of individual measurements in 5 minutes is

tm = 300/((57+58)/2)=5,2

Thus, for the certified test gas concentration results a relative uncertainty of:

%56,12,5

15,1

22 PGu

The expanded relative uncertainty (p=95%) for the test gas concentration is

therefore UPG = 3,12 %.

11. Documentation

The testing protocol ―Certification of test gas cylinders‖ is to be used for the documentation

of the test gas cylinder certification

Date: Name:

Component:

Reference

measurement device:

sr:

%

Response time: ta: tf:

Reference standard: Set point: UL-RS: %

Test gas cylinder: Set point (producer):

144

Test gas certification:

Uncertainty calculation

2300

2

22

fa

rRSLPG

tt

sUu

uPG = % x2 = UPG = %

Observations:

......................................................................

Date/ Signature

Gravimetric Determination of PM10 Concentration by

means of the

High-Volume-Sampler DIGITEL DHA-80

Content

1. Scope 146

2. Build-up of the DIGITEL DHA-80 146

3. Description of Measuring Procedure 146

4. Execution of Sampling 147

4.1 Parametrisation and Sampling Control 147

4.2 Measurement Operation and Maintenance 148

5. Execution of Gravimetric Analysis 149

5.1 Calibration of the Semi-Micro Balance 149

5.2 Filter Handling 149

Measured

values

Average value=

145

5.3 Filter Weighing – Reference Filters 150

5.4 Calcultation of PM10 Concentration – Humidity Correction 150

6. Quality Assurance 151

7. Documentation 151

8. Appendix: Calibration of Air Sample Flow Volume with a Diaphragm Meter 152

146

1. Scope This Standard Operation Procedure describes the gravimetric analysis performed in the framework of PM10 concentration measurements with the High Volume Sampler DIGITEL DHA-80. The DIGITEL dust sampler works fully automatic with a maximum of 15 individual filters and regulated air flow volume. A fractionated sampling system PM10 is usually used in field operations. The particles from the ambient air are gathered on conditioned round filters by means of a blower. In the subsequent lab analysis the PM10 mass is determined through differential weighing. The whole procedure is aimed at the assessment of the PM10-concentration pollution. The sampling procedure described here is based upon the VDI (Association of German Engineers) guideline 2463 Blatt 11, which describes the technical data, the procedure parameters and the assessment in comparison with the basic procedure. The calibration of the air flow volume takes place on a yearly basis by means of a diaphragm meter of the type G40 (Qmin = 0,4 m3/h; Qmax = 65 m3/h).

2. Build-up of the DIGITEL DHA-80 The automatic filter exchange mechanism, which is either brought under in a weather-proof box housing, or is built in a 19 inch housing, is operated electronically and handles up to 15 filters from a filter container. The air sample flow volume is regulated by set-point value. With fractionated sampling PM10 for instance, the necessary flow volume in order to reach a maximum of pre-separation is 30m3/h. The control electronics are located in the upper part of the devices. By means of a multi-line display and a keyboard, the device settings can be interrogated and parameters can be changed according to task. In the lower capsulled part there is a blower and a frequency converter. By means of a flow volume measuring device with a floater, the flow volume can be adjusted through a movable photo sensor. The mechanic filter exchange takes place in a motion sequence shortly before a new filter is loaded in the flow chamber through the start of the blower. Shortly before the desired starting point, a changing fork grabs the finished sample from the filter holder and leads it from the flow chamber back to the filter container. In the end, holders are released and the finished sample falls downwards. At the same time, a new filter falls into the changing fork and is led into the flow chamber. After ensuring that the filterholder is not jammed, a new sampling begins. Thanks to the fact that the filter holders are all equipped with sealing rings on one side the filters are not contaminated when stored in the device.

3. Description of Measuring Procedure By means of the DIGITEL High Volume Sampler PM10-concentrations as well as dust substances are determined according to current requirements of national and international standards with regard to limit value monitoring. Very important features for particle measurements are the gravimetric analyses of daily samples. In view of further investigations, for heavy metals for instance, selection criteria with regard to the filter material can be taken into account in advance. A fractionated sampling with a high air flow rate still leads to high detection sensitivity for concentration of wanted elements, even if a partial filter analysis is performed.

147

4. Execution of Sampling 4.1 Parametrisation and Sampling Control

The properly maintained and calibrated measuring device is brought to the measuring site and is connected to the power supply. Attention should be paid to the stability of the device, to the possibility of free air inflow and to the right sampling height of the single-stage impactor. Then, the parametrisation of the measuring sensors and the device control in view of the performance requirements is performed by means of the keyboard. First, the sampling of air pressure is calibrated: MENU… 2. PARAMETER INPUT… 5 OPERATION MODE… 1 OPERATION CONFIGURATION… 1 TEMP. CORRECTION… cursor to „p (uncal) [mbar]“ Here, the current air pressure from the measuring site is entered and confirmed with ENTER Warning! During data input there should be no filter in the flow chamber and the blower must be off. With the key EXIT, return to the initial window. The introduced air pressure value should not vary more than +/- 2 mbar. In the following stage the period and frequence of sampling is set: MENU…2.PARAMETER INPUT…4 PERIOD SETTING … Here, in the „Work“ field the sampling period is introduced in minutes (e.g. daily sample=01440). With „Pause“ a sampling interval can be programmed in the same way. In practice it is only worked with pauses when not all measuring days of the assessment period are needed for the determination of a time-referenced average. For the calculation of the results, following information is necessary: the status condition of the ambient air as well as the total air volume, as average values from the sampling period. The parametrisation can take place in such manner, that only the desired data appears in the printer protocol at the end of the sampling. Warning! The protocol contains neither the filter number nor the filter-holder number. It is only possible to track a filter sample to protocol data by means of the date and the link in the sampling protocol. In the following, an example parametrisation is rendered: Instrument ID: Hannover 106-N Filter change at overload off Stop time at power cut off Only failure indication messages off Blower capacity on Blower capacity equal/over 90 % off Blower power sensitivity (%): 2 # Blower on/off off 4-day-sampling off Bayern-Hessen-Protocolon Protocol-mode: 0

148

Bayern-Hessen-Address: 310 Bayern-Hessen-ID: 310 Current blower capacity Printer operation on Press./temp. correction on kN (Correction factor – standard) on kM (Correction factor – environment) on VN m3 (total air volume – standard) on VM m3 (total air volume – environment) on Send average Press/Temp on TN °C: (standard conditions 273 K) 0 pN mbar: (press. standard) 1013 p(uncal) mbar: (uncalibrated) 1007 pM mbar: (current pressure in system) 998 TM °C: (temperature in system) 12,9 Flow through l/min: 506 Wind measurement off The input is confirmed with ENTER. The EXIT key takes back to the initial window. The measuring device can only be equipped with filter holders and can only be started according to performance requirements. In the case of a pre-programmed start, the first filter must already be in the flow chamber. For this, filter change must be set on manual change. When turning the knob for manual change, the changing fork travels from the flow chamber to the filter container. Before the fork reaches its final position, the tray of the filter holder, which usually takes on the loaded filters must be manually moved upwards and held until a flat surface is created for the filter holder transportation. This manually produced resistance at the fall of the first filter is imperative because otherwise no filter can be pushed into the flow chamber. Later, the exiting filter holder creates the surface, so that the new one can be deployed fricitonless. The starting time is programmed as follows: MENU ... 1 START PROGRAMME ... 1 YY:MM:DD hh:mm Then, ENTER and EXIT to the initial window. The start time, usually 00:00 o‘clock, is shown. The status of the DIGITEL is then, the same as in older versions: „Waiting―. 4.2 Measurement Operation and Maintenance

At the set start time the blower starts sucking in sample air with the preset flow volume. While the filter resistance is growing, the system adapts the air flow volume, which is at the same time recorded in the print protocol. Any failure taking place during sampling is also recorded in the print protocol and taken into consideration with decisive parameters if necessary. When the set number of minutes is reached, the blower turns off. Usually, daily samples are produced. If a new measurement follows immediately, or else after a desired pause, a new filter is introduced automatically shortly before the start. With a fully loaded container fifteen individual measurements can be carried out according to the programme.

149

After 14 days of sampling operation the single-stage pre-separation needs to be cleaned and greased. Normally, it is enough in this interval to change the impactor plate and to check the nozzles for rougher impurities. The whole sampling system should be cleaned quarterly. To this purpose, the sampling is interrupted and the pieces disassembled. The surfaces on which sample air glides can be easily cleaned of particles with a damp cloth. After the elements are put back together, the blower can be operated shortly without a filter in order to ensure that remaining particles do not reach the sampling filters.

5. Execution of Gravimetric Analysis For the gravimetric analysis we use a semi-micro balance from the company Sartourius AG, Göttingen, type MC 210 P. This balance has a large enough weighing tray and is suited for this measuring task thanks to its 10 µg readability. 5.1 Calibration of the Semi-Micro Balance

The calibration with standard weights takes place yearly in the framework of a maintenance contract and is performed by employees of the of the production company. Before every weighing, an internal adjustment (zero and calibration point) takes place automatically shortly after the device is switched on. After that, the device is ready to be used. 5.2 Filter Handling

Two filter materials can be used, according to the performance requirements: cellulose nitrate and quartz fiber filters. Usually, cellulose-nitrate filters produced by Sartorius AG, Göttingen: ord. no. 11342-150-----G; pore size 5 µm; packages of 25 pieces with a diameter of 150mm are used. When needed, the filters are taken individually with teflon-tweezers and laid in glass petri dishes of 180 mm and then marked with consecutive numbers. On each side, very close to the edge, the same number is stamped twice with the same number by means of a numbering stamp. The assignned numbers are recorded in a protocol, so that it is ensured, that a filter number is only used once. Next, the filters are taken to the weighing laboratory for equilibration, and the glas cover is lifted and laid down slightly on the side. If further analyses follow, for instance for anions, ammonium or carbon, quartz fibers need to be used. The material of the company Schleicher & Schüll from Dassel has proved suitable to our requirements, from the point of view of handling and blank value quality. The company offers under the name QF 20, 50 pieces with a diameter of 150 mm under REF.NO.: 10373208. Before the filters are put in petri dishes in the balance room, they have to be subjected to a supplementary cleaning of sticking lints in order to improve the quality of the weighing. For this, the filters are blown individually and on both sides with nitrogen, until the surfaces and the margins are cleaned of chads. In a subsequent stage, a conditioning follows in view of the analysis of organic and elementary carbon. All organic impurity should be reduced to a minimum by a 4-hour glow in a muffle kiln at 840 ° C. After that, the numbering and equilibration in the balance room follow as previously described.

150

5.3 Filter Weighing – Reference Filters

After the filters have stayed for at least 48 hours in the climatized balance room, a safe assessment of the filters/dust mass is possible. Before beginning the works, the balance is switched on, and an automatic calibration follows. An adequate weighing protocol is prepared. Besides the balance type, the filter material and the dimension of the result are recorded. During the following weighing the filter number, the mass, the air humidity and the date are written down in a row for every filter. After the calibration is finished, the stop of the blinking signal and the zero sign on the display show that the balance is ready for weighing. The filters are staticly discharged by means of an ionizing blower, right before they are placed onto the weighing tray. During the time in which the weighing result stabilises, a clock is running which has been started after the closing of the balance room. After every two minutes the result is read and recorded. The gravimetricly analysed filters remain in the petri dishes until their utilization. The backweighing of the loaded filters takes place the same way, after an equilibration of minum 48 hours. Attention should be paid that no rough particles, insects or plant parts which were not gathered during sampling stick to the filters. These are to be carefully removed beforehand with a pair of tweezers. The results of the filter mass determination are to be recorded in the weighing protocol after exactly two minutes. In every weighing process, so called reference filters are weighed at the same time. Such reference filters of both filter types are to be available with no exception in the balance room, in order to enable the description of the water balance of the filter material between the two weighing dates. By means of the mass differences resulting from the modified climate conditions in the balance room, the filter masses can be corrected subsequently. 5.4 Calcultation of PM10 Concentration – Humidity Correction

The calculation of the filter masses is performed by means of the in- and back weighing. For this, an Excel worksheet is used, in which, besides the humidity correction, the relation to the air sample volume can be established. The mass difference between initial weighing and back weighing is the net mass. This is corrected by means of the net mass resulting from the weighing of reference filters in the same measuring days, on which an initial weighing an back weighing has been performed. The reference filter mass can be negative, which means that the weighing result consists of a part of water which can not be attributed to the sampling. If the reference filter mass is positive for example, then the air humidity at the back weighing was higher than the one at the initial weighing. In both cases the result should be corrected in such a way that the mass determination is based on the same framework conditions. After the correction, the result is the absolute mass related to the conditions during sampling. For the relative result of PM10 concentration, the air sample volume over the period of the sampling is to be used. As reference unit, the conditions during sample inlet prevail. This is why, during standardised sampling, the temperature and air pressure are to be recorded. The sample air volume in

151

environment conditions must be converted to the average temperature and the average air pressure during sampling. The result is rendered as PM10 concentration of airborne particles in µg/m3

6. Quality Assurance The quality assurance of PM10 concentration comprises the technical part of the device, filter handling including transport and gravimetric analysis. The DIGITEL runs in a very reliable way, so that operation can be ensured with little maintenance effort and one yearly calibration. When the filter is changed, the position of the photo sensor on the rotameter should be verified visually, in order to ensure pre-separation during PM10 sampling. The greasing of the impactor plate should conventionally be performed after approximately 15 filters. In the case of lower temperatures, the effect of the greased pre-separation is to be kept by means of a contact heater. The filter handling has a great influence upon the results of PM10 measurements. Especially conditioning residues in the case of quartz fibre filters and humidity inflow in the case of cellulose nitrate filters are to be met actively. The filters have to be checked for damage before use and during weighing and removed if necessary. Filter transportation is performed conventionally at temperatures of maximum 25°C. In summer, insulated containers, together with pretreated cooling elements are used for this. Maintenance on the analytical balance is performed once a year by specialised staff of the producer. Linearity shall be checked with calibrated comparison weights. Additionally, the internal calibration will be activated before each weighing. In order to minimise static charge, the cellulose nitrate filters are subjected to ion blowing shortly before being placed onto the weighing tray. The influence of the varying air humidity in the weighing lab will be corrected through calculations by means of comparison weighings with reference filters.

7. Documentation The complete traceability of PM10 measurements related to gravimetric analysis requires a complex documentation of different working areas. In order to be able to handle the large number of filters and to be able to relate them to the sampling parameters, a multiple linkage of data is performed in the respective protocols. There are filter release protocols, weighing protocols and sampling protocols. To each of the five DIGITEL devices 35 filter holders are assigned, which are numbered and also have a serial number which is separated by a full stop from the numbering. (e.g. device no. 733, filter holder serial no. 1.3 ... 35.3). All working protocols of the sampling are stored in project related files in room 139 and are kept for ten years. Moreover, the validated measuring results are managed and archived in the computer in room 122. From here, the present measuring results can be accessed any time.

152

8. Appendix: Calibration of Air Sample Flow Volume with a Diaphragm

Meter Work base:

Filter release protocol, weighing protocol, sampling protocol and printer protocol of the

DIGITEL

Calibration of Air Volume Flow with a Diaphragm Meter

The calibration of air volume flow is performed with a calibratable diaphragm meter of the

type G40 (Qmin = 0,4 m3/h; Qmax = 65 m

3/h) from the company Elster Handel.

To this purpose, the measuring device and the meter are placed one near the other in the lab.

The air sample leading system is connected to the diaphragm meter by a hose with a 40 mm

diameter. (image 1). By means of a T-piece, a ramification is created for a low-pressure-

measurement between the meter and the measuring device, so that a U-pipe manometer can be

connected. At the entrance of the meter, a temperature measurement is installed. The current

air pressure (see 4.1) has to be parametered when the measuring device is switched off. The

photo sensor must be positioned on the rotameter in such a way that the corresponding ‗Cut

off‘ in reached at the sample inlet. For PM10 measurements, the air flow volume point value

is of= 500 l/min (30 m3/h) related to environmental conditions.

Once all measuring and verification devices are installed, in order to take into consideration

the pressure difference, a filter holder with the filter material to be used later is introduced

into the flow channel. The counter status, the temperature at air inlet and air pressure are

recorded in a protocol. When the DIGITEL is started the time must be taken to write down the

low pressure in front of the the meter for comparison measurements. The calibration

measurement can last up to 24 hours. If there are adjustments to the photo sensor, then the

measurement must be repeated.

After the programmed time is over (e.g. 1440 minutes), a time comparison is made, the

counter status on the meter, temperature and air pressure are recorded. From the DIGITEL,

the sampling protocol is taken, which comprises the sampling period, the average

temperature, the average pressure in the system (air pressure – pressure difference of the

fiters) and the total air volume. The calculation of the comparison air volume is also

performed under the standard conditions 273 K and 1013 hPa.

For field measurements, the pressure measuring device and the termperature measurement at

sample inlet of the DIGITEL are to be calibrated, respectively to be adjusted. In order to

create a relation with environmental conditions, the average measured values during the

sampling period are to be used for calculations. The calibration of air pressure measurement is

usually done by relating it to the sea level. In order to be able to render the environmental

conditions correctly when relating them to the measured value, the air pressure must be

corrected by means of the altitude of the measuring place.

In the following, the data of a calibration measurement are opposed.

153

Flow Volume Calibration on DIGITEL

With Diaphragm Meter G40

air pressure at location pA-hPa 986 counter status gas meter after m3 3562,492

air pressure (standard) pREF -hPa 1013 counter status gas meter

before

m3 3518,006

low pressure at rotameter pLOK-hPa -68 total volume m3 44,486

temperature reference value tREF-K 288 time measurement min 89,4674

temperature at rotameter tLOK-C 24,8 temperature at gas meter C 20,6

flow volume on scale qSKALA-l/min 505,52 low pressure on gas meter hPa -1

scale pieces acc. to table 15C;

1013hPa

131

operation-flow volume-

probe head

qLOK-l/min 502,75 =point value 500l/min for

PM10

standard flow volume-

rotameter

qNORM-l/min 448,60 standard flow volume gas

meter

NI/mi

n

449,56

standard flow volume in 24

hours

m3/24h 646,0 m

3 647,4

m3/24

h

comparison measurement m3-Total 40,2 m

3-

Total

40,3

Deviation in percent: -0,2 %

DIGITEL No.: 192-N

Verification medium QF

Date 29.01.03

Bild 1

154

Filter release protocol Filter labelling with number stamp

Cellulose-nitrate-filter – 150 mm, 5 µm pore size

All filters to be used in the different measurement programmes are labelled consecutively with a

sequential (four-digit) number.

Sequential

number

Sequential

number

Date Hand signal

from 1 to 199 14.03.02 KI

from 120 to 155 15.05.02 GL

from 156 to 215 17.05.02 AI

from 216 to

from to

from to

from to

from to

from to

from to

from to

from to

from to

from to

from to

from to

from to

from to

from to

from to

Weighing Protocol

Balance type:___MC210P___Filtermedium:___CNF___Format:___150__mm

Date Filter

no.

No. Initial

Weighing

%

r.F.

Date Backweighing %r.F. Date

1.3

2.3

3.3

4.3

155

5.3

6.3

7.3

8.3

9.3

.

.

.

17.3

18.3

19.3

20.3

21.3

22.3

23.3

24.3

25.3

26.3

27.3

28.3

29.3

30.3

31.3

32.3

34.3

35.3

156

Sampling Protocol

Monitoring station Bösel Month Year 2003

Meas. device no 733 Control internal Flow through rate 503 ltr/min

Start time (clock) 0:00 Pause time 1440 dust exposure time 1440 min

Filter type CNF Pore size 5 µm

cons. Filter Filter holder Sampling Standard volume Observations

No. No No Date m3

1

2

3

4

5

6

7

8

9

10

11

12

13

14

15

16

17

18

19

20

Immissionsmessungen

PM2.5-Konzentration in der Außenluft

Probenahme mit dem High-Volume-Sampler DIGITEL DHA-80

Gravimetrische Staubmassenbestimmung

157

Inhaltsverzeichnis 1 Anwendungsbereich 2 ..........................................................

2 Aufbau des Messgerätes ........................................................................ 2

3 Beschreibung des Messverfahrens ........................................................ 3

4 Durchführung der Probenahme 4 ................................

4.1 Parametrieren der Probenahmesteuerung .................................. 4

4.2 Messbetrieb und Instandhaltung ................................................ 6

5 Durchführung der Gravimetrie 7 ..........................................................

5.1 Kalibrierung der Halbmikrowaage ............................................ 7

5.2 Behandlung der Filter 7

5.3 Wägung der Filter 9 .........................................................

5.4 Berechnung der PM2.5-Konzentration ............................................... 10

6 Qualitätssicherung 10

7 Abweichungen zur Vorschrift 11

8 Dokumentation 13 .........................................................

9 Mitgeltende Unterlagen ....................................................................... 14

10 Verantwortliche ................................................................................... 14

11 Literatur 15

Anhang

Kalibrierung des Probenluftvolumenstroms mit einem Balgengaszähler

Arbeitsvorlagen:

Filterausgabe-, Wiege-, Probenahme-, und Druckerprotokoll des DIGITEL

158

1 Anwendungsbereich

Diese Standard-Arbeits-Anweisung (SOP) beschreibt die Gravimetrie im Rahmen der PM2.5-

Konzentrationsmessungen mit dem High Volume Sampler DIGITEL DHA-80. Der DIGITEL

Staubprobensammler arbeitet vollautomatisch mit max. 17 Einzelfiltern und geregeltem

Luftvolumenstrom. Beim Feldeinsatz kommt ein fraktionierendes Probenahmesystem PM2.5

zum Einsatz. Mit Hilfe einer Saugturbine werden die in der Außenluft dispergierten Partikel

auf konditionierten Rundfiltern gesammelt. In der sich anschließenden Analyse im Labor

wird durch Differenzwägung die PM2.5-Masse bestimmt. Das gesamte Verfahren dient der

Bewertung der PM2.5-Konzentrationsbelastung als Referenzmessverfahren.

Das hier beschriebene Probenahmeverfahren begründet sich auf die Europäische Richtlinie

DIN EN ISO 14907:2005 in der die technischen Daten als auch die Verfahrenskenngrößen

aufgeführt sind. In einem nationalen Ringversuch (Wiesbaden 2003) ist die Äqivalenz von

PM10-Bestimmungen gem. EN 12341 zum Referenzverfahren nachgewiesen worden. Die

damaligen Rahmenbedingungen des Messverfahrens und die Verfahrenskenngrößen der

Gravimetrie sind auf die PM2.5-Messungen mit dem DIGITEL übertragbar. Die Kalibrierung

des Luftvolumenstroms erfolgt jährlich mit einem DKD-kalibrierten Balgengaszähler Typ

G40 (Qmin = 0,4 m3/h; Qmax = 65 m

3/h).

2 Aufbau des Messgerätes

Die in einem wetterfesten Gehäuse montierte Filterwechselautomatik arbeitet elektronisch

gesteuert bis zu 17 Filter aus einem Vorratsmagazin nacheinander ab. Der

Probenluftvolumenstrom wird dabei über einen fest eingestellten Sollwert geregelt. Bei der

fraktionierenden Probenahme PM2.5 beispielsweise muss der Volumenstrom zum Erreichen

des „cut off― 500 l/min am Probeneingang betragen.

Im oberen Teil der Geräte befindet sich die Steuerelektronik. Über ein mehrzeiliges Display

und ein Tastenfeld können Geräteeinstellungen abgefragt als auch Parameter

aufgabenorientiert verändert werden. Im unteren, gekapselten Teil, sind eine Saugturbine und

der Frequenzumrichter untergebracht. Mit Hilfe einer Schwebkörper-

Volumenstrommesseinrichtung, die sich etwa mittig links im Gerät neben der

Filterbeströmungskammer befindet, kann über eine bewegliche Lichtschranke der

Volumenstrom justiert werden. Der mechanische Filterwechsel erfolgt in einem

Bewegungsablauf direkt nach Beendigung der Probenahme. Dabei fährt eine am Umfang des

Filterhalters greifende Gabel die fertige Probe aus der Beströmungskammer zurück in das

Filterhaltermagazin. In der Endstellung werden Halterungen freigegeben wodurch die fertige

Probe nach unten fällt. Gleichzeitig fällt ein neuer Filterhalter in die Gabel und wird in die

Beströmungskammer geschoben. Nach dem der Filterhalter dicht eingeklemmt ist kann eine

159

erneute Probenahme beginnen. Durch die mit Dichtungsringen versehenen Filterhalter wird

gewährleistet, dass während der Probenahme keine Falschluft gezogen wird und dass die

Filter bei der Lagerung im Gerät nicht kontaminiert werden.

3 Beschreibung des Messverfahrens

Mit Hilfe des DIGITEL High Volume Samplers können PM2.5-Konzentrationen in der

Außenluft entsprechend den Anforderungen an ein Referenzmessverfahren durchgeführt

werden. Wichtigstes Merkmal im Hinblick auf den Referenz-Status sind bei der

Partikelmessung die gravimetrischen Analysen von Tagesproben im Bezug auf ein Masse-

Normal. Der Probenluftvolumenstrom wird mit einem DKD-kalibrierten Balgengaszähler in

der Regel vor einem Messauftrag kalibriert und nach dessen Beendigung (12 Monate)

rekalibriert. Umfangreiche eigene Untersuchungen haben gezeigt, dass innerhalb dieser

Zeitspanne die Messunsicherheiten der Volumenstrom-Kalibrierung kleiner als 2 % sind.

4 Durchführung der Probenahme

4.1 Parametrieren der Probenahmesteuerung

Das gewartete und kalibrierte Messgerät wird an den Messort gebracht und an die

Stromversorgung angeschlossen. Auf die Standfestigkeit des Gerätes, die freie

Anströmbarkeit der Luft und die entsprechende Distanz zu möglichen Emissionsquellen des

Staubsammlers ist zu achten. Über die Tastatur wird anschließend die Parametrierung der

Messsensoren und der Gerätesteuerung im Hinblick auf die Aufgabenstellung vorgenommen.

Zuerst wird die Luftdruckmessung kalibriert:

MENUE ... 2 PARAMETEREINGABE ... 5 BETRIESMODUS ... 1

BETRIEBKONFIGURATION ... 1 TEMP.KOMPENSATION ... Cursor bis ... „p (uncal)

[mbar]“ An dieser Stelle wird der aktuelle Luftdruck am Messort eingegeben und mit

ENTER bestätigt. Achtung! Während der Eingabe soll sich kein Filter in der

Beströmungskammer befinden und die Turbine muss ausgeschaltet sein. Mit der Taste

ZURÜCK in das Ausgangsfenster. Der eingegebene Luftdruckwert sollte nicht mehr als +/- 4

hPa (Auflösung) schwanken.

160

Im nächsten Schritt werden die Dauer und die Häufigkeit der Probenahme eingestellt:

MENUE ... 2 PARAMETEREINGABE ... 4 ZUSTANDSZEITEN ... An dieser Stelle wird

unter „Work“ die Dauer der Probenahme in Minuten eingetragen (z.B. Tagesprobe = 01440).

Unter „Pause“ kann ein Probenahmeintervall in der gleichen Weise programmiert werden. In

der Praxis wird immer dann mit Pausen gearbeitet, wenn für die Bildung eines zeitbezogenen

Mittelwertes nicht alle Messtage des Beurteilungszeitraumes benötigt werden.

Für die Berechnung der Ergebnisse werden die Probenluftvolumina erfasst. Die

Zustandsbedingungen der Umgebungsluft werden als Mittelwerte über den

Probenahmezeitraum integriert und bei der Berechnung des Probenluftvolumens VA

berücksichtigt. Die Parametrierung kann so erfolgen, dass nur die gewünschten Daten auf

einem Druckerprotokoll am Ende der Probenahme erscheinen. Achtung! Das Protokoll enthält

weder Filter- noch Filterhalternummer. Die zeitliche Zuordnung der Filterprobe kann nur

anhand der Filterhalternummer und des Datums entsprechend der Vorgaben im

Probenahmeprotokoll sicher nachvollzogen werden. Im Folgenden wird beispielhaft eine

Parametrierung wiedergegeben:

Gerätekennzeichen:

HRSW 194 PM2.5 QAT

Filterwechsel bei Überlastaus

Zeit bei Netzausfall anhalten aus

Nur Störmeldungen aus

Turbinenleistung ein

Turbinenleistung ab 90 %aus

Turbinenleistung Empfindlichkeit (%): 2

# Turbine ein/aus aus

4-Tages-Proben aus

Bayern-Hessen-Protokoll ein

Protokoll-Mode: 0

Bayern-Hessen-Adresse: 310

aktuelle Turbinenleistung ein

Druckerbetrieb ein

p/T Kompensation ein

kN (Korrekturfaktor – Norm) aus

kM (Korrekturfaktor – Umgebung) aus

VN m3 (Gesamtluftvolumen – Norm) ein

VA m3 (Gesamtluftvolumen – Umgebung) ein

mittlere/n p/T ausgeben ein

TN °C: (Normbedingungen 273 K) 0

161

pN mbar: (Normluftdruck) 1013

p(uncal) mbar: (unkalibriert) 1007

pM mbar: (Aktueller Druck im System) 998

TM °C: (Temperatur im System) 12,9

TA °C: (Temperatur außen) 6,9

Durchfluss l/min:520 (Rotameterbezug)

Die Eingaben werden jeweils mit ENTER bestätig. Mit der Taste ZURÜCK wird das

Ausgangsfenster angesteuert. Das Messgerät kann nun mit Filterhaltern bestückt und

entsprechend der Aufgabenstellung gestartet werden. Bei einem vorprogrammierten Start

muss sich das erste Filter bereits in der Beströmungskammer befinden. Zu diesem Zweck

wird der Filterwechsler auf Handbetrieb gestellt. Durch das Drehen des Handrades fährt die

Gabel aus der Beströmungskammer in das Vorratsmagazin. Noch bevor die Gabel die

Endstellung erreicht hat, muss der Auffangteller, der in der Regel die beaufschlagten Filter

aufnimmt, von Hand so weit nach oben bewegt und gehalten werden, bis sich eine ebene

Fläche für den Filterhaltertransport ergibt. Dieser von Hand ausgelöste Widerstand beim

Fallen des ersten Filters ist unumgänglich, da sonst kein Filter in die Beströmungskammer

geschoben werden kann. Später bildet der herausfahrende Filterhalter die Ebene, so dass der

neue reibungslos zum Einsatz kommt. Die Startzeit wird anschließend wie folgt

programmiert:

MENUE ... 1 PROGRAMM STARTEN ... 1 JJ:MM:TT ss:mm Danach ENTER und ZURÜCK

ins Ausgangsfenster. Die Startzeit, meist 23:59 Uhr wird angezeigt. Das Gerät befindet sich,

wie auch bei älteren Bauausführungen angezeigt, im Zustand: „Waiting―.

4.2 Messbetrieb und Instandhaltung

Zum Zeitpukt des Starttermins beginnt die Saugturbine mit dem voreingestellten

Volumenstrom die Probenluft anzusaugen. Mit zunehmendem Filterwiderstand regelt das

System den Luftvolumenstrom entsprechend nach welches zugleich im Druckprotokoll

festgehalten wird. Störungen während der Probenahme werden ebenfalls im Druckerprotokoll

vermerkt und ggf. bei den bestimmenden Parametern berücksichtigt. Nach Erreichen der

Probenahmedauer (1440 Minuten) schaltet die Saugturbine ab. In der Regel werden

Tagesproben erzeugt. Nach der Probenahme wird unmittelbar ein neues Filter automatisch

eingelegt.

Nach einem Probenahmebetrieb von 14 Tagen muss die einstufige Vorabscheidung gereinigt

und gefettet werden. Normalerweise reicht es in diesem Intervall die Prallplatte

auszutauschen und die Düsen auf grobe Verunreinigungen zu überprüfen. Die Reinigung des

162

gesamten Probenahmesystems erfolgt vierteljährlich. Zu diesem Zweck werden die

Probenahme unterbrochen und die Bauteile grob zerlegt. Mit einem feuchten Tuch werden die

probenluftführenden Oberflächen von anhaftenden Partikeln gesäubert. Nach dem

Zusammenbau erreicht man mit einem kurzzeitigen Saugbetrieb ohne Filter eine Reinigung

von noch vorhandenen Partikeln im Probenahmesystem.

5 Durchführung der Gravimetrie

Zur Durchführung der gravimetrischen Analyse wird eine Halbmikrowaage mit einem

Messbereich von ca. 200 g verwendet (z.B. Typ MC 210 P; Fa. Sartorius). Diese verfügt über

einen entsprechend großen Wägeteller und wird mit einer Auflösung von 10 µg der

Messaufgabe ausreichend gerecht.

5.1 Kalibrierung der Halbmikrowaage

Eine DKD-Kalibrierung mit Eichgewichten wird einmal jährlich im Rahmen eines

Wartungsvertrages durch Mitarbeiter der Herstellerfirma durchgeführt. Vor jeder Wägung

wird kurz nach dem Einschalten ein interner Abgleich (Null- und Eichpunkt) automatisch

eingeleitet. Danach ist das Gerät einsatzbereit. Ein weiterer automatischer Abgleich erfolgt

bei laufendem Betrieb stündlich.

5.2 Behandlung der Filter

Aufgrund unterschiedlicher Aufgabenstellungen können verschiedene Filtermaterialien wie

Cellulose-Nitrat-, Glasfaser- und Quarzfaser-Filter zum Einsatz kommen.

Bei Cellulose-Nitrat-Filtern verwenden wir Produkte mit einer Porengröße von 5,0 µm und

einem Durchmesser von 150 mm. Die Filter werden bei mit Teflon- oder Metallpinzette

einzeln in 180 mm große Glaspetrischalen gelegt und anschließend mit einer fortlaufenden

Nummer gekennzeichnet. Die vergebenen Nummern werden auf einem Protokoll

festgehalten, so dass gewährleistet wird, dass Filternummern nur einmal verwendet werden.

Anschließend werden die Filter im Wägelabor zum Äquilibrieren ausgelegt, wobei der

Glasdeckel angehoben und leicht verschoben abgelegt wird.

Sollen weitere analytische Untersuchungen bestaubter Filter beispielsweise auf Anionen,

Ammonium oder Kohlenstoff nachfolgen, müssen Quarzfaser-Filter verwendet werden. Filter

163

werden aufgrund der großen Anzahl an Messgeräten als Jahresbudget in einer Bestellung

beschafft. Die Produkte können wechseln, da es mehrere Anbieter mit Filtermaterial

unterschiedlicher Qualitätsmerkmale und Preise gibt. Aufgrund vieler Unwägbarkeiten bei

erstmalig verwendeten Produkten können messtechnisch relevante Verfahrenskenngrößen die

Bewertung der Gravimetrie stark beeinflussen. Jedes neue Produkt erfordert daher eine

eingehende Prüfung aller Verfahrenskenngrößen.

Seit November 2007 werden in der Hauptsache Quarzfaser-Filter (z.B. PALLXP56 der Fa.

PALL Life Sciences) mit einem Durchmesser von 150 mm verwendet. Bevor die Quarzfaser-

Filter in den Petrischalen im Wägelabor ausgelegt werden, müssen sie zur

Qualitätsverbesserung einer zusätzlichen Reinigung von anhaftenden Fusseln unterzogen

werden. Die Filter werden dazu einzeln von beiden Seiten mit Stickstoff abgeblasen. Bei den

zurzeit eingesetzten, vorgeglühten Filterprodukten, kann auf eine weitere Konditionierung im

Hinblick auf organische Inhaltsstoffe verzichtet werden. Im Anschluss an die beschriebene

Vorreinigung erfolgen das Aufstempeln der Filternummern und die Äquilibrierung im

Wägelabor.

5.3 Wägung der Filter

Nach Ablauf von mindestens 48 Stunden Verweilzeit der Filter im klimatisierten Wägelabor

ist ein sicheres Abschätzen der Filter/Staubmasse möglich. Vor Beginn der Arbeiten wird die

Waage eingeschaltet und eine automatische Kalibrierung eingeleitet. Nach Abschluss der

Kalibrierung wird durch das Aufheben des Blinksignals und der Nullstellung im Display die

Wägebereitschaft angezeigt. Ein entsprechendes Wägeprotokoll wird vorbereitet. Neben dem

Waagentyp werden das Filtermaterial und die Dimension des Ergebnisses festgehalten. Bei

der sich anschließenden Wägung werden für jedes Filter zeilenweise die Filternummer, die

Masse, die Luftfeuchtigkeit und das Datum notiert. Mit Hilfe eines Ionengebläses können die

Cellulose-Nitrat-Filter unmittelbar bevor sie auf dem Wägeteller abgelegt werden statisch

entladen werden. Über den Zeitraum, indem sich das Wägeergebnis stabilisiert, läuft eine

Uhr, die nach dem Schließen des Waagenraumes gestartet wird. Nach jeweils zwei Minuten

wird das Wägeergebnis abgelesen und notiert. Zu Schluss werden aus den gravimetrisch

analysierten Filtern mit einem Keramikwerkzeug sechs Ø 39 mm große Teilfilter ausgestanzt

164

und in entsprechend beschrifteten Kunststoffdosen luftdicht verschlossen abgelegt (Raum

403).

Die Rückwage der beaufschlagten Filter erfolgt in der gleichen Weise nach einer

Äquilibrierung von mindestens 48 Stunden. Es ist darauf zu achten, dass keine groben

Partikel, Insekten oder Pflanzenteile auf den Filtern haften, die nicht der Probenahme

zuzuordnen sind. Diese sind zuvor mit einer Pinzette oder durch leichtes Schlagen auf den

Filterhalterrand bei nach unten gerichteter Bestaubungsfläche vorsichtig zu entfernen. Das

Ergebnis der Filtermassenbestimmung wird wiederum nach exakt zwei Minuten im

Wägeprotokoll vermerkt.

Bei jedem Wägevorgang werden drei Referenzfilter mitgewogen. Referenzfilter beider

Filterarten liegen dazu ausnahmslos im Wägelabor um einen variierenden Wasserhaushalt der

Filtermaterialien zwischen den beiden Wägeterminen beschreiben zu können. Mit Hilfe der

Massendifferenzen die aus den veränderten klimatischen Rahmenbedingungen des

Wägeraums resultieren können anschließend die Filtermassen korrigiert werden.

5.4 Berechnung der PM2.5-Konzentration

Die Berechnung der Staubmassen wird mit den Wägeergebnissen der Ein- und Rückwaage

durchgeführt. Dazu wird ein Excel-Arbeitsblatt verwendet indem neben der

Feldblindwertkorrektur auch der rechnerische Bezug mit dem Probenluftvolumen erfolgt.

Durch Differenzbildung der Massen aus Ein- und Rückwaage, abzüglich der

Feldblindwertmasse, erhält man die PM2.5-Staubmasse. Die Feldblindwertmasse kann negativ

sein weil am Tag der Einwaage eine deutlich höhere rel. Luftfeuchtigkeit im Wägeraum

herrschte als bei der Rückwaage. Ist die Feldblindwertmasse positiv, so lag die

Luftfeuchtigkeit bei der Rückwaage über der bei der Einwaage. In beiden Fällen ist das

Ergebnis entsprechend zu korrigieren, da die Massenbestimmung auf den gleichen äußeren

Rahmenbedingungen beruht. Nach der Korrektur erhält man die absolute PM2.5-Masse

bezogen auf die örtlichen Bedingungen bei der Probennahme. Für das relative Ergebnis der

PM2.5-Konzentration erhält man durch die Division mit dem Probenluftvolumen über den

Zeitraum der Probennahme. Als Bezugsgröße sind die Bedingungen am Probeneinlass

maßgebend. Bei der standardisierten Probennahme sind daher die Temperatur und der

165

Luftruck kontinuierlich zu erfassen. Das Ergebnis wird als PM2.5-Konzentration des

Schwebstaubes in µg/m3 angegeben.

6 Qualitätssicherung

Die Qualitätssicherung der PM2.5-Konzentrationsmessung umfasst den Teil der Gerätetechnik,

die Filterhandhabung einschließlich des Transportes und die Gravimetrie. Das DIGITEL läuft

nach unserer Erfahrung sehr zuverlässig, so dass der Betrieb mit wenig Wartungsaufwand und

nur einer jährlichen Kalibrierung sichergestellt werden kann. Visuell überprüft wird bei jedem

Filterwechsel die Lichtschrankenstellung am Rotameter wodurch die beabsichtigte

Vorabscheidung bei der PM2.5-Probe-nahme gewährleistet wird. Das Fetten der Prallplatte soll

konventionsgemäß nach ca. 15 Tagesproben durchgeführt werden. Bei tieferen Temperaturen

ist die Wirkung der gefetteten Vorabscheidung durch eine Kontaktheizung aufrecht zu

erhalten.

Die Handhabung der Filter hat einen großen Einfluss auf die Ergebnisse der PM2.5-

Messungen. Insbesondere den Verarbeitungsrückständen bei Quarzfaser-Filtern und dem

Feuchtigkeitseinfluss bei Cellulose-Nitrat-Filtern muss aktiv begegnet werden. Die Filter

müssen vor dem Einsatz und bei der Wägung auf Beschädigungen untersucht und ggf.

verworfen werden. Der Transport der Filter wird bei subjektiv erträglichen

Fahrzeuginnentemperaturen durchgeführt. In der Regel können mit den heute allgemein

üblichen Klimaanlagen in den Fahrzeugen überdurchschnittliche Temperaturen vermieden

werden. Aufgrund der hohen Filterzahlen ist eine separate Kühlung während des Transports in

Fahrzeugen nicht realisierbar.

Die Analysenwaage wird einmal jährlich durch Fachpersonal der Herstellerfirma gewartet

und gemäß den Anforderungen des DKD (Deutscher-Kalibrier-Dienst) kalibriert. Dabei wird

u. a. die Linearität mit geeichten Vergleichsgewichten überprüft. Arbeitstäglich wird vor jeder

Wägung zudem die interne Kalibrierung aktiviert. Um statische Aufladungen zu minimieren

werden die Cellulose-Nitrat-Filter kurz vor dem Auflegen auf den Wägeteller einem

Ionengebläse ausgesetzt. Der Einfluss durch schwankende Luftfeuchtigkeit im Wägelabor

wird mit Hilfe von Vergleichswägungen mit Referenzfiltern rechnerisch korrigiert.

7 Abweichungen zur Vorschrift

Folgende Arbeiten werden nicht entsprechend den Vorgaben der DIN EN ISO 14907:2005

durchgeführt. Für das Abweichen gibt es zwingende Gründe, insbesondere ist der erhebliche

166

Mehraufwand beim Wiegen und Konservieren der Filter nach eigenen Untersuchungen

fachlich nicht zu rechtfertigen.

1. Prüfen der Waagenlinearität:

Eine Prüfung im Messbereich mit zusätzlichen Eichgewichten ist nicht notwendig. Die DKD-

Kalibrierung mit einhergehender Linearitätsprüfung ist laut Herstellerangaben zur

Qualitätssicherung für ein Wartungsintervall (Jahr) ausreichend.

2. Wiederholwägungen nach minimal 12 Sunden:

Unsere Filterproben werden anhand von Blindwertfiltern und ggf. Referenzfiltern korrigiert.

Die Blindwertfilter entsprechen jeweils dem „Bearbeitungsalter― der eingesetzten

Filtercharge. Hierdurch werden graduelle Anpassungen berücksichtigt die sich nach dem

Herausnehmen aus dem Filterpack an der Umgebungsluft ergeben. Insbesondere

Quarzfaserfilter zeigen, wenn sie aus dem Verpackungsstapel genommen werden, noch

deutliche Gewichtszunahmen. Die Referenzfilter liegen ständig im Wägelabor aus und

können somit der Korrektur bei schwankender Luftfeuchtigkeit dienen. Da sich die

Luftfeuchrigkeitsschwankungen mittels linearer Regression sehr gut korrigieren lassen sind

Messunsicherheiten dieses Verfahrensschrittes mit 1,4 % bei CN-Filtern und 1,1 % bei

Quarzfiltern als sehr gering zu bewerten.

Nach eigenen Untersuchungen konnten Filtermassen auf diese Weise bis zu 25 Tagen

hintereinander bestätigt werden. Wir verwenden die nach zwei Minuten anstehende

Messgröße der Masse, wenn die Anzeige der Waage zu diesem Zeitpunkt stabil ist.

3. Volumenstromkalibrierung:

Für die Volumenstromkalibrierung wird ein DKD-kalibrierter Balgengaszähler verwendet.

Die Messunsicherheit dieser Prüfeinrichtung liegt lt. Herstellerangaben bei 0,51 %. Die mit

dem Balgengaszähler erzeugte Kalibriergröße wird erst ab und kleiner einer Differenz von

0,15 m3 gegenüber des DIGITEL-Volumens akzeptiert. Hierfür wäre eine Messunsicherheit

von ca. 0,25 % zu berücksichtigen. Die Volumenstromkalibrierung mittels Balgengaszähler

ist mit einer erweiterten Messunsicherheit von 1,2 % deutlich besser zu bewerten als eine

Volumenstromkalibrierung mittels zusätzlichem Rotameter. Eigene Untersuchungen haben

ergeben, dass aufgrund der Schwebkörperschwankungen nur eine Ablesegenauigkeit von ca.

2 % zu erreichen ist. Kalibriert werden die Geräte für die Messkampagne eines Jahres.

Danach erfolgt eine Rekalibrierung. Bei eigenen Prüfungen waren zwischen dem Beginn und

dem Ende von Messkampagnen Abweichungen von deutlich weniger als 2 % feststellbar. So

genannte Feldkalibrierungen entfallen daher.

4. Verluste an leichtflüchtigen Partikeln:

167

Die beaufschlagten Filter werden in dem Sammler bis zu einem Monat gelagert. Dabei liegen

sie unterhab der Bestaubungsebene aufeinander und dichten sich gegenseitig ab. Das einzelne

Filter kann abhängig vom Probenahmeintervall bis zu 48 Stunden mit der Umgebungsluft in

Wechselwirkung stehen. Anschließend wird es mit einem weiteren Filterhalter abgedeckt. Bei

eigenen Versuchsreihen wurden bei Doppelbestimmungen aus einem Gerät die Filter

arbeitstäglich in das klimatisierte Wägelabor gebracht, während im anderen Gerät die Filter

über zwei Wochen verblieben. Anhand der ausgewerteten Messreihen ließ sich kein

signifikanter Unterschied zwischen beiden Messreihen erkennen. Die Messunsicherheit betrug

0,5 µg/m3 bei einem Konzentrationsbereich von 10 µg/m

3 bis 63 µg/m

3. Der zusätzliche

Aufwand ist daher nicht gerechtfertigt.

8 Dokumentation

Die lückenlose Nachvollziehbarkeit der Arbeitsschritte im Rahmen der PM2.5-Probenahme in

Verbindung mit der Gravimetrie erfordert eine umfangreiche Dokumentation der

verschiedenen Arbeitsebenen. Um die Vielzahl der Filter handhaben und die

Probennahmeparameter sicher zuordnen zu können wird in den entsprechenden Protokollen

eine Mehrfachverknüpfung der Daten vorgenommen. Wir unterscheiden Filterausgabe-,

Wäge- und Probennahmeprotokolle. Den einzelnen DIGITEL-Geräten sind jeweils 36

Filterhalter mit fortlaufender Nummerierung und einer durch einen Punkt abgesetzten

Seriennummer zugeordnet (z.B. Gerät Nr. 733, Filterhalterserie: 1.3 bis 36.3). Alle

Arbeitsprotokolle der Probenahme sind in projektbezogenen Akten im Filterlabor Raum 403

abgelegt. Daneben werden die validierten Messergebnisse auf dem Dezernatslaufwerk

Jahrgangsweise verwaltet und archiviert. Von hier können die aktuellen Messergebnisse

jederzeit angefordert werden.

Alle Arbeitsprotokolle der Probenahme sind in projektbezogenen Akten im Filterlabor Raum

403 abgelegt und aufbewahrt. Daneben werden die validierten Messergebnisse auf einem

Dezernats-Server Jahrgangsweise verwaltet und archiviert. Von hier können die aktuellen

Messergebnisse jederzeit angefordert werden.

9 Mitgeltende Unterlagen

Die im Folgenden aufgeführten Formblätter werden zum Teil für handschriftliche

Aufzeichnungen und zur automatischen Berechnung der Ergebnisse (Excel-Arbeitsblätter)

168

verwendet. Zur Vermeidung von Übertragungsfehlern sind die Formblätter entsprechend dem

Layout der elektronischen Arbeitsblätter vergleichbar aufgebaut (Anhang).

10 Verantwortliche

Die für die Gravimetrie im Rahmen der PM-Feinstaubmessungen mit dem DIGITEL DHA 80

verantwortlichen Personen werden in der Liste der Verantwortlichkeiten benannt.

11 Literatur

VDI-Richtlinie 2463 Blatt 11

Messen von Partikeln – Messen der Massenkonzentration (Immission) – Filterverfahren –

Filterwechsler DIGITEL DHA-80

DIN EN 12341:1999

Luftbeschaffenheit – Ermittlung der PM2.5-Fraktion von Schwebstaub – Referenzmethode

und Feldprüfverfahren zum Nachweis der Gleichwertigkeit von Messverfahren und

Referenzmessmethode

DIN EN 14907:2004

Luftbeschaffenheit – Gravimetrische Referenzmessmethode für die Bestimmung der

PM2.5-Massenfraktion des Schwebstaubes

Richtlinie 1999/30/EG des Rates

Richtlinie über Grenzwerte für Schwefeldioxid und Stickstoffoxide, Partikel und Blei in der

Luft (1. Tochterrichtlinie)

22. Verordnung zur Durchführung des Bundes-Immissionsschutzgesetzes

Verordnung über Immissionswerte für Schadstoffe in der Luft – 22. BImSchV

169

170

Anhang

Kalibrierung des Luftvolumenstromes mit einem Balgengaszähler

Die Kalibrierung des Luftvolumenstromes wird mit einem DKD-kalibrierten Balgengaszähler

der Firma Elster Handel vom Typ G40 (Qmin = 0,4 m3/h; Qmax = 65 m

3/h) durchgeführt.

Hierzu werden das Messgerät und der Gaszähler nebeneinander im Labor aufgebaut. Der

Probeneinlass des DIGITEL wird mit einem Schlauch von 40 mm Durchmesser saugseitig mit

dem Balgengaszähler verbunden (Bild 1). Mittels eines T-Stücks wird eine

Unterdruckmessung zwischen Gaszähler und Messgerät durchgeführt. Am Eingang des

Gaszählers wird die Außentemperaturmessung des DIGITEL installiert. Bei ausgeschaltetem

Messgerät (ohne Filter) muss der aktuelle Luftruck (siehe unter 4.1) parametriert werden. Die

Lichtschranke am Rotameter ist so zu positionieren, dass der entsprechende ‚Cut off‗ am

Probeneingang erreicht wird. Bei PM10-Messungen beträgt der Soll-Luftvolumenstrom = 500

l/min (30 m3/h) bezogen auf Umgebungsbedingungen.

Wenn alle Mess- und Prüfgeräte installiert sind werden zur Berücksichtigung der

Druckdifferenz mehrere Filterhalter mit dem später zu verwendenden Filtermaterial in das

Messgerät gelegt. Nach jeweils fünfminütiger Probenahme wird zum Schluss der mittlere

Druckwiderstand des Filtermaterials ermittelt. Aus dem Druckwiderstand, der Höhenlage der

Messstelle in Bezug auf NN und der mittleren Jahrestemperatur am Messort wird der

Sollvolumenstrom für die Rotametereinstellung berechnet. Derselbe Wert muss zur

Berechnung des Gesamtvolumens einer Probenahme entsprechend parametriert werden.

Vor dem Beginn der Vergleichsmessung wird der Zählerstand am Gaszähler notiert. Nach

dem Probenahmestart werden die Startzeit und der Unterdruck zwischen Gasuhr und

DIGITEL ebenfalls auf dem Kalibrieprotokoll festgehalten. Die Kalibriermessung kann bis zu

24 Stunden dauern. Bei jeder Nachjustierung der Lichtschranke muss die Vergleichsmessung

wiederholt werden.

Nach Ablauf der voreingestellten Messzeit (z.B. 1440 Minuten) wird ein der Zählerstand vom

Gaszähler vermerkt. Alle übrigen Probenahmeparameter die sich auf dem Kurzprotokoll des

DIGITEL befinden werden für die Berechnungen in einem Excel-Arbeitsblatt verwendet.

Filter Handling (Cellulose-Nitrate; Quartz Fibre) for

171

Establishing the PM 10 Concentration with the DIGITEL DHA 80

Content

1. Scope 171

2. Preparations for the Equipment Supply 171

3. Equipment Supply 172

4. Filter Postprocessing for Backweighting 172

1. Scope The procedure instructions apply to establishing the TSP, respectively the PM10-, PM2.5 with the DIGITEL DHA 80 dust collector.

2. Preparations for the Equipment Supply

- Clean the lab table. Place the filter holders (adequate serial number X.1 - X. 6) on the

lab table in a chronological order with the filter holder number in front. From left to

the right complete the sequence with other filter holders according to necessity.

- Place the corresponding petri dishes (same numbers as the filter holders) with the

weighed filters behind the respective holders. Control the match between the filter

holder number and the dish number.

172

- Record the filter holder number in the sampling protocol together with the previously

established date of the sampling and connect with the filter number. Control through

samples the stamped filter numbers, so as to ensure an unequivocal assignment of

numbers. The previously established sampling date shall be transferred onto the petri

dishes.

The filters from the petri dishes shall be placed centrally into the holder, the teflon

ring shall be placed on carefully and clamped with the tension ring. Place the opening of the tension ring on the filter holder number. This helps with the processing, so that the filter holder number is easy to localise without much search on the front side.

- The filter holders shall be placed into the portable container with the smallest number

face up. The corresponding sampling protocol shall be copied and enclose with

identical information into the portable container.

- The petri dishes shall also be placed in chronological order (smaller numbers

up) in the adequate shelf.

3. Equipment Supply - Open the device: The following visual verifications are to be carried out: For a

running device should the rotational solid be in abeyance (500 l/min)? Are there errors pointed out on the display, or in the recorder protocol? Do all the light diodes show a plausible functioning mode? Control and make a short mention on the sampling protocol that the foreseen filter is in the dust chamber. If the case may be, document the changed existing situation with the number of the filter holder and the date in the sampling protocol.

Place new filter holders chronologically into the device. The maximal assignment

allowed only if the last filter is fixed into the guiding rod. Take the adequate quantity of charged filters from the device. Pay attention to the blank value! This should be on the lowest place and for the entire foreseen month.

Is there for the upcoming time period without supervision enough recorder paper

in stock? Add new recorder paper.

4. Filter Postprocessing for Backweighting

Place the filter holders on the lab table in a sequence from left to right with the marking in front. Should there be big loose impurities on the filters, they should be shaken off before.

Place the petri dishes behind the filter holders according to the numbers. Check

the completeness, sequence and sampling date on the dish against the sampling protocol. In case of disfunctions in the sampling, that are clear in the recorder

173

protocol, the adequate correction shall be noted. Note the obvious contaminations in the sampling protocol.

Loosen the tension rings, carefully remove the teflon rings and the filter, if need

be, shake again lightly and place into the petri dish. Take the petri dishes with the filters if possible immediately after the collection into the weighing chamber. Position the dish covers lightly for a balancing of min. 48 hours.

- The filter holders, tension rings and teflon rings are to be cleaned immediately

and stocked up in the foreseen place for new usage. The teflon rings must be wet cleaned and rubbed off individually. The filter holders must be free of loose dust or cakings, before they are stored in the board in a chronological order, the smallest number to be seen up, in front. The petri dishes are to be cleaned quarterly with clean press air.

Preparation and Storage of Filters (Cellulose - Nitrate;

Quartz Fibre) for Establishing the PM10 Concentration

through

DIGITEL DHA 80

Content

174

1. Scope 174

2. Sampling with Cellulose-Nitrate-Filters 174

3. Sampling with Quartz-Fibre-Filters 175

1. Scope The procedure instructions apply to establishing the TSP, respectively the PM10-, PM2.5 with the DIGITEL DHA 80 dust collector.

2. Sampling with Cellulose-Nitrate-Filters

Filter type: Cellulose-Nitrate-Filter (CNF) from Sartorius AG, Göttingen; Ø 150 mm

Order-No.: 11342-150--------G pore size 5 µm (25 pcs/unit)

Quarz fibre filter (QF 20) from Schleicher & Schüll, Dassel; Ø 150 mm

Ref.NO.: 10373208 (50 pcs/unit)

Cellulose-Nitrate-Filter: With the teflon tweezers the filters are put into the petri dish (on a separating paper). Previously, the needs for filters for the measurement task shall be established before the next replacement deadline. Therefore according to the numbering of the filter holders of the DIGITEL dust collector the petri dishes are to be prepared in chronological order. The filters shall be subsequently marked twice on the edge line with a continuous number stamp. The allotted number sequences shall be recorded in the "Filter issue protocol" as assigned.

Immediately afterwards the just assigned filter numbers and petri dish numbers (identical with the filter holder numbers) shall be recorded in the "Weighing Protocol". The filters shall be taken into the balance room for weighing (>48 hours).

Only weigh the filters in a stabile relative air humidity! On the meteorology recorder (hair hygrometer) no important drifts should be recognisable before the weighing. In

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the period of about three weighings no significant fluctuations of the relative air humidity (max. 0.6 %) may appear; in order to ensure a qualitative analysis.

In order to equip the filter holders, these shall be placed chronologically and in parallel with the same numbered petri dishes on the work table. After placing and fixing the filters in the holders, the filter holder numbers and the date until the chosen replacement deadline shall be written into the "Sampling Protocol" and so firmly linked in advance. At the same time, the filter numbers shall be transferred into the sampling protocol as supplementary identification support. The date of the sampling shall be marked with a waterproof pen on the petri dish under observance of a blank value.

After the admission of the filters in the DIGITEL sampler these shall be placed back into the petri dishes in the previously described work manner. The filters shall be taken into the balance room for weighing (>48 hours).

During the backweigh the same stable conditions shall exist in the balance room as for the weighing of the filters. When a filter is pending for weighing, the data of the weighing, the relative air humidity and the data of the sampling (from the petri dish) shall be recorded into the "Weighing Protocol". The filter number on the back side of the filter shall be controlled by samples.

The gravimetrically evaluated filters shall be separated with a ceramic tool into test parts for storage. For this the filters shall be cut axially with a ceramic knife and stapled. With three possible cuttings (Ø 39 mm) one can obtain six partial filters. These shall be placed in staples in adequately marked preparation containers. Each container shall be labelled with the data describing the sample:

Measurement place ( HRSW ) Filter holder number ( 15.4)

Filter number ( 387) Date (dd.mm.yy)

Volume (m3)

The blank value filters shall, as all used filters, be stored according to their belonging in time (blank value/mm/yy)

in preparation containers as partial filters.

3. Sampling with Quartz-Fibre-Filters Quartz Fibre Filters: The quartz fibre filters shall be operated identically as the cellulose-nitrate-filters, with the

following exceptional work steps: Each contact with the quartz fibre filters is only permitted with flat metallic tweezers. Before weighing, the quartz

fibre filters have to be cleaned with nitrogen against adherent fuzzes. Subsequently they are to be heated in a muffle kiln at least 4 hours at 850 °C and after cooling and placing them into the petri dishes they are to be assigned continuous numbers. The filter issue numbers shall be kept separately in an identical protocol, a confusion of identical filter numbers is excluded due to the filter type and its distinct use. Also the median substance allows afterwards clear inferences on the filter medium. For analyses with a high expected level of volatile substances, the gravimetric analysis must be carried out quickly. The filters shall be protected from heat influence above 25 °C and shall be kept after the cut until the analysis in the refrigerator.

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Analytical Balance Manual

Verification of the electronic analytical balance

MC 210 P

Content

177

1 Scope 178

2 Balance specifications 178

3 Monthly brief verification 178

4 Repeatability check 179

5 Balance handling and maintenance 179

6 Annexes 180

178

1 Scope This procedure instruction applies to the field ―Area related immission measurement‖ in department 4.6. It describes the recurring quality assurance measures for the analytical balance MC 210 P produced by the company Sartorius, Göttingen. The balance is located in the air-conditioned weighing room in a steady state, on a vibration-minimising substructure. The balance is used for analytical tasks. It is also employed as a test device for pipette calibration.

2 Balance specifications Name: Semi-micro balance MODEL: MC 210 P Test device no.: 1044 Weighing capacity: 210 g Readability: 0, 00001 g Readout: Display Producer: Sartorius AG, Göttingen Maintenance contract: yes (annual)

3 Monthly brief verification The monthly brief verification is performed in order to assess and ensure the full operational readiness of the balance. It is completed up to the fifth working day of each month and it is documented in the annexed form. If complaints are made, the persons responsible visibly block the balance for all users. The brief verification is performed using a 200 g stainless steel cylinder, quantified as ―Mass Reference Standard‖. The check weight is calibrated and certified annually - externally, by an accredited institution (German Calibration Service DKD). The measurand for each year and the respective deviation tolerances are written down in the form. The current reference standard valid for the year 2004 Stainless steel cylinder with clutch nut (class E2) Id.: ZM 971 Test device no.: 1045 Nominal mass: 200 g Set point: 199, 99991 g Measurement uncertainty: 10 µg Calibration date: 15.01.04 Resubmission: January 2005 (recalibration) The brief verification form is updated as a spreadsheet in an EXCEL workbook. After the monthly brief verification, the form is printed, signed by the person responsible and placed in the file ―Balance Manual‖ and also as visible document above the balance in the weighing laboratory. If the brief verification is unsuccessful, the

179

balance is blocked and an analysis of causes is carried out; also, the head of the calibration lab is informed. The form must be updated annually and becomes valid after the new calibration value of the check weight has been filled in. The check weight must be weighed three times at monthly interval and the weight recorded in the log in the columns Test 1-Test 3. The ―Result‖ column will contain the result of the brief verification. It must end with ―YES‖ three times; otherwise the verification must be repeated. If any one of the test results is still passed with a ―NO‖, the maintenance service must be called in - after consultation with the management department.

4 Repeatability check The quarterly repeatability check is also performed using the stainless steel cylinder mentioned above. The check weight is placed on the weighing pan six consecutive times, after an internal calibration (function control) has been manually initiated and completed. The measurement results are recorded into a workbook; consequently an automatic evaluation thereof is carried out. The form is printed, signed by the person responsible and placed in the file ―Balance manual‖. If repeatability is not achieved the check must be repeated. If the balance fails the repeatability check it is blocked and an analysis of causes is carried out. The form is updated annually.

5 Balance handling and maintenance The analytical balance must be checked for damages and impurities before every use. One must also make sure that the balance is in a firm position on the vibration-minimising substructure and that its working plane is levelled correctly. After turning on the device the user must wait for the internal calibration to be completed before beginning with the weighing. In case of damages or improper operation the balance must be blocked and the superior and the rest of the users informed. A maintenance contract was signed with the company Sartorius AG. The works comprise an annual inspection and a linearity test with check weights, as well as specific works according to the requirements of the German Calibration Service (DKD). The maintenance certificate consequently issued is filed in the balance manual. Performing a cause analysis for troubleshooting involves restoring the functional capability of the balance as soon as possible, after consultation with the rest of the users. If this is not achieved the balance must be blocked visibly for any other activity. In consultation with the management department the repair service will be called in. All exceptional works on the balance, such as repairs with a consequent new start of operation must be documented carefully and must be kept in the balance manual for at least three years. All users must be informed thereof.

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6 Annexes Form: Brief verification (monthly)

Form: Repeatability (quarterly)

Form: Balance maintenance (annually)

Monthly brief verification of the analytical balance - MC 210 P - (Test device)

Balance ID: MC 210 P Co. Sartorius, Göttingen (Semi-micro balance)

Test device number: INV. No.: NLÖ 000178

Check weight: 200 g ID: ZM 971

Calibration set point: 199.99991 g From 15.01.04

Tolerated deviation: 0.2 g (0.1‰ of the mass)

Month

Date

Check weight mass (g) Result Hand sign

2004 Test 1 Test 2 Test 3 Brief verification

successful

January 15.02.04 200.19870 200.10560 199.89960 YES YES YES

February NO NO NO

March NO NO NO

April NO NO NO

May NO NO NO

June NO NO NO

July NO NO NO

August NO NO NO

September NO NO NO

October NO NO NO

November NO NO NO

December NO NO NO

Alternate date NO NO NO

Alternate date NO NO NO

Alternate date NO NO NO

Repeatability of the analytical balance - MC 210 P - (Test device)

Balance ID: MC 210 P Co. Sartorius, Göttingen (Semi-micro balance)

Test device number: INV. No.: NLÖ 000178

Check weight: 200 g ID: ZM 971

Calibration set point: 199.99991 g from: 15.01.04

Tolerated deviation: 0.2 g (0.1‰ of the mass)

Check weight mass (g)

Repeated

measurement

1st quarter 2

nd quarter 3

rd quarter 4

th quarter Additional

date

Additional

date

Additional

date

Date: 15.01.04

1 200.19991

181

2 200.15863

3 200.00254

4 200.04763

5 199.99933

6 199.95873

Average value: 200.06113 #DIV/0! #DIV/0! #DIV/0! #DIV/0! #DIV/0! #DIV/0!

Standard

deviation:

0.09663 #DIV/0! #DIV/0! #DIV/0! #DIV/0! #DIV/0! #DIV/0!

Result

Repeatability: YES #DIV/0! #DIV/0! #DIV/0! #DIV/0! #DIV/0! #DIV/0!

Notes:

182

Annual maintenance of the analytical balance - MC 210 P - (Test

device) according to DKD

Balance ID: MC 210 P Co. Sartorius, Göttingen (Semi-micro balance)

Test device number: INV. No.: NLÖ 000178

Date: Activity description Agent Person in charge

15.07.03 Maintenance, linearity check (according to DKD) A. Kunze H. Glauche

Notes:

Pipette Manual

Verification of the Piston-Driven Air Displacement Pipette

by an Analytic Balance

Content

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1 Scope 184

2 Basis of the Procedure 184

3. Equipment, Test Agents, Chemicals 184

4 Execution of the Verification 185

5 Findings and Measures 185

6 Annexes 186

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1 Scope These procedure instructions apply to the calibration lab. They describe the measures for quality assurance in the operation of piston-driven air displacement pipettes. The pipettes are located in room xx. The piston-driven air displacement pipettes are checked yearly for their accuracy and precision. The right technique of using the piston-driven air displacement pipettes is explained in detail in the instruction manual. Each user has the obligation to be familiar with the operation of pipettes in order to avoid errors due to inappropriate operation.

2 Basis of the Procedure During the pipetting errors can occur due to inappropriate operation and also due to unrecognised flaws of the pipette. The functional efficiency of the pipettes is therefore to be ensured before each usage. Therefore a few test pipettings shall be carried out, while the complete evacuation of the pipette head is trained practically every working day. In case of uncertainties with regard to the functional efficiency or the correct volume, a verification with an analytic balance shall be carried out. This verification of all piston-driven air displacement pipettes that is usually to be carried out once every year is the object of the present procedure instructions.

3. Equipment, Test Agents, Chemicals Various piston-driven air displacement pipettes (with fixed or variable volume ranges) with adequate pipette tips. Use only original pipette tips or adequate tips that are certified for conformity. Slim beaker, diameter - height ration = 1:3, nominal volume starting with 20 ml (moisture trap, respectively watchglass). Beaker for test pipetting (150 ml). For all the pipettes with a nominal volume of 10 µl or more, a semi-micro balance from Sartorius with a weighing range of 210 g shall be used for the verification of the volume (room 127). The quality assurance measures for the balance are in the procedure instructions: The test agents supervision and the verification of the electronic analytic balance MC 210 P are regulated. The functional capability shall be tested accordingly before use. Further test agents to be provided in the weighing chamber are a thermometer - measuring range 0 - 100°C, resolution 0,1 °C and a barometer, resolution 1hPa. For operation use completely desalinated water (pure water), produced with an ion exchanger and a subsequent cleaning with the NANOpure II (Barnstead) with at least 16 MegOhm/cm in the pulping lab in room 137. Before the preparation in the weighing lab, where the water is brought to the room temperature within at least 48 hours, the water is to be degased in an open container for about 15 minutes in ultra sonic bath.

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The ready-made forms are to be used for a complete record of the necessary parameters.

4 Execution of the Verification Upon the yearly test the pipettes together with their tips, as well as the previously named devices and aids shall be brought into the weighing room for the preparation of the comparative weightings about two days before the due date. All the parts that influence the establishment of the volume must achieve in this way the same operation temperature. Before the beginning of all the works the functional efficiency of the test and verification devices must be ensured. Maintenance works and if the case may be, cleaning works are also to be finished beforehand. The first test line of the ten repeated weightings is started with an internal balance calibration. In the weighing protocol the parameters for the identification of the test item shall be documented in the meantime. Afterwards, the beaker is placed in the middle of the measuring pan. After the display of the (closed) balance is stable, the zero point is tared with the TARA-Taste. With the newly inserted pipette tips a series of five test pipettings are carried out in a separate beaker. This procedure is used for the creation of a humidity balance of the air in the cavities, and for the observation of the secure evacuation of the pipette tip during the adequate operation. The pipette tip shall be at an angle of 30 – 45 ° above the liquid level on the containers wall during the dosage. During the "blow out" the orifice of the tip is wiped off gently on the interior wall of the container in order to dispose of the last drop of liquid. Should everything go well, the first test pipetting is done with a new head in the separate beaker, before making the real test in the beaker on the measuring pan. The mass result and the temperature shall be recorded into the weighing protocol. A weighing shall take 60 seconds at the most, the procedure is to be respected very precisely. After further 60 seconds the actual result shall be recorded in the column "Mass loss ‗. The second measurement result serves the ulterior correction of the humidity loss due to the open weighing container. There at least nine subsequent repeated weighing according to the following scheme: ‚Change tip‗ – ‚moisten once the new tip‗ – ‚establish the TARA-weight (key)‗ – ‚dosage of test volume‗ – ‚establish the BRUTTO-weight‗ – ‚wait 60 seconds and establish the „correction - weight― – ‚change tip‗ etc. ... The ten repeated weightings are to be carried out with new tips. In the case of obvious erroneous measurements, the pipetting shall be continued until ten usable results are achieved. The results of the weightings are to be recorded into the weighing protocol(s) of the above mentioned work files after the finalisation of the manual works. The average temperature as well as the air pressure during the series of weightings is to be recorded with due precision (0,5 °C; 1 hPa). The (separate!) recording of the year of the test is important. Only afterwards is the corresponding result range identified and the findings are recorded in the "Form ‗.

5 Findings and Measures The calculations are made automatically on the basis of the provisions of DIN EN ISO 8655-6 on the worksheet and are compared to the margin of error given by the producer. Accuracy and precision are indicated independently under Test Result with „OK― or „defective―. Both results "OK" lead to the finding: "pass", in this case the

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pipette is released for further use. Should accuracy or precision be "defective" under a certain point, the result of the test is "failed". In this case an analysis of the causes has to be carried out. This comprises maintenance and cleaning according to the operation instructions. If even through this measure no correct testing is achieved, the pipette must be sent to reparation with the agreement of the administration. The further users shall be informed thereof. Each new acquired piston-driven air displacement pipette, as well as each pipette received back from reparation shall be subject to a complete test with an electronic analytic balance. The documentation on the basis of the forms is to be continued yearly and stored in the folder Pipette Manual in room xx. At the place of the pipettes copies of the forms are to be provided for quick reference for the users. The responsible testing marks the validity of the document through a signature in the year column.

6 Annexes

Form: Weighing Protocol

Form: Verification of Accuracy and Precision

Lists: Pipette Inventory

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189

Calibration of the Reference Standard

Organisation and Deadlines

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Content

1 Scope 191

2 Brief verification 191

3 Annual Testing 191

4 External DKD-Calibrations 192

5 Organisation 192

6 Documentation 193

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191

1 Scope These procedure instructions apply to the calibration lab. They describe the recurrent calibrations of the reference standard as a basis for the traceability of the air quality measurements results to the national and international standard. The necessary work steps are provided in the following and are binding: One must make a distinction between the reference standards that as test agents need an external calibration according to the requirements of the German Calibration Service (DKD). Or so called functional tests of work devices that along the factory-made calibration must undergo regular brief verification. By means of a computer-based reminder system, the organisation of the annual transmission of the reference standard for the calibration is ensured in due time.

2 Brief verification The semi micro balance MC 210 P in room 127 as well as the piston-driven air displacement pipettes in the analytical labs must undergo a monthly (or if the case may be every working day) brief verification. This measure is for finding the errors that can appear due to inappropriate operation or not recognised flaws. Through the test the unlimited operational readiness of the devices is confirmed. Every quarter the repeatability must be proven. The result shall be documented in an EXCEL file for one year and stored under xx with the name of the activity and the year. For a failed test, a cause analysis must be carried out. The balance is to be blocked visibly from further use. With the piston-driven air displacement pipettes a few test pipettings shall be carried out prior to each daily use. From the last calibration protocol that has to be within reach and visible from the storage location it is necessary to be able to get a clear idea on the unrestricted operational readiness of the device.

3 Annual Testing It is bindingly provided that the works to be carried out annually are the calibration of the semi-micro balance through an external expert and the calibration of the piston-driven air displacement pipettes, according to an international norm, through the own employees. There is a contract on the DKD conform calibration of the semi-micro balance with the Sartorius AG company. The balance is provided with an adequate sticker, while the certificate is deposited in the balance manual. The piston-driven air displacement pipettes are calibrated according to the agreement, with the semi-micro balance, activated through a memory protocol of the in-house deadlines schedule for all users. The results of the calibration are to be deposited in the pipette manual (room xx) and within reaching range from the storage location of the pipettes. Each pipette found at the storage location in a special pipette holder is calibrated and usable without restrictions. Each faulty pipette is provided with an adhesive sticker and is removed from the holder. Besides of the error protocol a reparation is to be commissioned and the other users are to be informed thereof.

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The reference standard kept for the traceability requires a DKD calibration that has to be repeated a one year intervals. Details are addressed in the next chapter.

4 External DKD-Calibrations The reference standard for: pressure, temperature, mass and volume must be sent to external calibration sites every year for the DKD conform calibration. Six weeks prior to the expiry date of the validity of the calibrations, a reminder is displayed to all users by the electronic deadline schedule. The reference standards are to be handled very carefully, especially it is to be taken into account the fact that a postal shipping must survive without damage from our responsibility. After the return of the reference standard the certificates are deposited into the manual "Reference Standard" (room xx). An adequate copy must be provided within reaching range from the devices. The resubmission is to be parameterised again in the deadline schedule with six weeks lead time.

5 Organisation The timely execution of the tests and calibrations is for a high quality work safety with a view to avoiding measurement errors. All the persons involved who depend in the daily work and results from the traceability to the reference standard, respectively from an appropriate calibration, are obliged reciprocally to maintenance, adequate operation and information in case of problems. The responsibilities on the frameworks of the recurrent tests and calibrations can only be transferred to other persons in the case of important obstacles.

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6 Documentation The in-house calibrations are usually analysed in EXCEL worksheets and are stored on a common drive. For the semi micro balance there are three worksheets: brief verification, traceability and maintenance. The monthly brief verification is adjusted for a year, this is why the year is included into the file name. The repeatability is adjusted every quarter for a year so that the file name is only extended with the year, The maintenance list is extended at least once a year with the record of the executed DKD calibration. In this list all the supplementary works for removal of faults, cleaning and so on must be recorded. The actual printout after each recurrent work according to the schedule shall be deposited in the balance manual (room xx) under "Device Manual ‗. For the piston-driven air displacement pipettes we distinguish two EXCEL worksheets according to the functioning mode - fixed or variable. The results of the calibration are saved through the pipette number with the year attached as an EXCEL file on the common drive. Besides the electronic data protection, also for the pipettes calibrations a paper printout must be deposited in the pipette manual under "Documentation ‗.

Jahresplaner 2005 K = Kurzprüfung R = Waagen - Reproduzierbarkeit

Jan 05 Feb 05 Mrz 05 Apr 05 Mai 05 Jun 05 Jul 05 Aug 05 Sep 051 Sa 1 Di 1 Di 1 Fr 1 So 1 Mi 1 Fr 1 Mo 1 Do

2 So 2 Mi 2 Mi 2 Sa 2 Mo 2 Do 2 Sa 2 Di 2 Fr

3 Mo 3 Do 3 Do 3 So 3 Di 3 Fr 3 So 3 Mi 3 Sa

4 Di 4 Fr 4 Fr 4 Mo 4 Mi 4 Sa 4 Mo 4 Do 4 So

5 Mi 5 Sa 5 Sa 5 Di 5 Do 5 So 5 Di 5 Fr 5 Mo

6 Do 6 So 6 So 6 Mi 6 Fr 6 Mo 6 Mi 6 Sa 6 Di

7 Fr 7 Mo 7 Mo 7 Do 7 Sa 7 Di 7 Do 7 So 7 Mi

8 Sa 8 Di 8 Di 8 Fr 8 So 8 Mi 8 Fr 8 Mo 8 Do

9 So 9 Mi 9 Mi 9 Sa 9 Mo 9 Do 9 Sa 9 Di 9 Fr

10 Mo K 10 Do K 10 Do K R 10 So 10 Di K 10 Fr K R 10 So 10 Mi K 10 Sa

11 Di 11 Fr 11 Fr 11 Mo K 11 Mi 11 Sa 11 Mo K 11 Do 11 So

12 Mi 12 Sa 12 Sa 12 Di 12 Do 12 So 12 Di 12 Fr 12 Mo K R13 Do 13 So 13 So 13 Mi 13 Fr 13 Mo 13 Mi 13 Sa 13 Di

14 Fr 14 Mo 14 Mo 14 Do 14 Sa 14 Di 14 Do 14 So 14 Mi

15 Sa 15 Di 15 Di 15 Fr 15 So 15 Mi 15 Fr 15 Mo 15 Do

16 So 16 Mi 16 Mi 16 Sa 16 Mo 16 Do 16 Sa 16 Di 16 Fr

17 Mo 17 Do 17 Do 17 So 17 Di 17 Fr 17 So 17 Mi 17 Sa

Fig. 1 Annual Planner Extract K = brief verification; R = repeatability

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Determination of measurement uncertainty for

nitrogen dioxide by means of an NO/NOx-

chemiluminescence-monitor

Content

1 Scope 194

2 Specification of measurement 195

3. Methods for the determination of measurement uncertainty 195

4. Cause and effect diagram 196

5. Quantification of uncertainty budgets 197

6. Calculation of the combined measurement uncertainty 210

7. Expanded measurement uncertainty 210

8. Documentation 210

9. Responsibility 212

10. Literature 212

11 Annex 213

1 Scope This standard operation procedure (SOP) describes the determination of the measurement

uncertainty for the measure nitrogen dioxide (NO2) in the air quality monitoring network. The

procedure is only valid for the use on site of properly maintained NO/NOx

chemiluminescence measurement devices, which are calibrated with the transfer standard gas.

The following contributions with regard to measurement uncertainty are a result of the

specific way of work in the monitoring network. By means of the co-action of technical and

analytical steps, the measure NO2 can be reduced to a nitrite-standard. The used nitrite

standard solution is traceable to the NIST-standard according to the information of the

producer.

The obligation to determine measurement uncertainty is based upon the requirements of DIN

EN ISO 17025. According to this, all uncertainty components of a measure, which are

relevant for a particular case, are to be subjected to an appropriate assessment process.

Different assessment approaches and model calculations are used in the process. The purpose

of these examinations is the description of data quality of nitrate dioxide air quality

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measurement values according to the requirements of the EU Directive 1999/30/EC. After

taking into consideration all possible error sources, the measurement uncertainty for nitrate

dioxide should be estimated by means of these considerations.

2 Specification of measurement The measurement uncertainty in continuous air quality measurements is to be regarded in

relation with the limit value to be assessed. Therefore, in the individual measurement, the

highest accuracy is to be reached near the limit value, according to the definition. With regard

to the estimation of the measurement uncertainty, at the specification of the measure, first it

must be verified to what extent the steps of the procedure or the method itself can influence

the result.

There are dependencies corresponding to the different procedures in the determination of

nitrate dioxide (NO2) in the process described here. These have to be checked separately and

have to be included in the uncertainty budget.

The configuration in image 1 shows the course of action schematically for the determination

of the measure nitrate dioxide at the calibration of the standard transfer gas/titration calibrator

CSI 1700. The titration calibrator CSI 1700 is a test device installed in the monitoring

network for the calibration of NO/NOx measurement devices and for the verification of

converter efficiency. In the following text, all individual steps of this method are reviewed

from the point of view of measurement uncertainty and are discussed in the end as extended

measurement uncertainty of the measure NO2.

Fig 1: Determination of the measure nitrate dioxide NO2 at calibration with the titration

calibrator CSI 1700 in the lab

3. Methods for the determination of measurement uncertainty Because of the very segmented procedure steps, the so called indirect approach was chosen.

In the first step, all available data from device manuals, external testing procedures and from

own measurements have been brought together.

Then, the interaction structure of the various uncertainty sources has been sketched. As it is to

be seen in picture 1, a NO/NOX measurement device has to be integrated in the determination

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procedure for methodical reasons. Therefore, the evaluation of the uncertainty contribution of

this device was also the object of these examinations. Thus, it was possible to demarcate the

measurement uncertainty of the transfer standard and to estimate the measurement uncertainty

of the measure NO2 for the result of the continuous air quality measurement at the same time.

The starting values are the following:

- Producer data, certificates or confidence ranges, results of receiving inspections.

- Representative test series: repeat determinations, repeated tests, calibration series

- Estimated values from examinations of third parties, plausibility tests.

4. Cause and effect diagram

For the identification of uncertainty sources a list of relevant influence measures of the whole

procedure has been compiled. Thus, four independent uncertainty sources arise:

1. Substance reference standard nitrate (NO2)

2. Reference measurement procedure

3. Transfer gas standard CSI - 1700

4. NO/NOX-chemiluminescence measurement device

The uncertainty sources can bear in themselves various uncertainty budgets, which result from

the manual work steps of a procedure.

In complex examination methods often many details are to be taken into consideration so as to

be able to safely estimate uncertainty budgets as part of the whole procedure. While

uncertainty budgets of a source are combined in the end, their specific effect can be verified

individually during quantification.

Uncertainty budgets of certain measures can amplify when combined with other uncertainty

sources or can even annihilate themselves. The following image shows which uncertainty

contributions may have an influence upon the NO2 measure to be determined.

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Fig. 2: Cause and effect diagram (fish-bone-diagram)

All arrows in the cause and effect diagram are possible uncertainty contributions at the

beginning of the uncertainty observation. The strongest arrows show the prevailing

uncertainty sources. The small arrows represent the uncertainty budgets, which in the end are

compiled to the combined measurement uncertainty of the source. During the examinations it

was ascertained by means of the uncertainty budget evaluation, that the contribution of the

photometer is approximately equal to that of the calibration curve. Therefore, in the

comprehensive survey only one uncertainty budget can be used. Because we as users have

chosen the contribution of the calibration curve, the uncertainty budget [photometer] has been

set in square brackets.

5. Quantification of uncertainty budgets The measure nitrogen dioxide (NO2) from the air quality monitoring network is traceable to

the nitrite standard solution of the company MERK that is traceable to the internationally

acknowledged NIST-standard, according to the certificate. Building upon this NO2-standard, a

defined NO2 test gas source is prepared for the monitoring network by means of the reference

measurement procedure (Saltzman) and with the transfer standard CSI 1700 (gas mixing

device combined with an NO gas mixture) and a measurement device commonly used in the

monitoring network. The air quality measure NO2 is therefore based on the substance

reference standard nitrite during calibration of the NO/NOX measurement devices with the

transfer gas standard.

In the following, all procedure steps are analysed for their uncertainty contribution as

illustrated in the cause and effect diagram. For simplification, mathematic formulas are not

included. However, during the evaluation reference will be made to the used model

calculations.

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Measurement uncertainty source 1

Substance reference standard nitrite; positioning of the calibration curve for the reference

measurement procedure

The following components were to be taken into consideration for the production of so called

comparison solutions:

- Pureness of the standard solution /parent solution ( R )

- Insert volume of the parent solution ( P )

- Solution volume of the comparison solution ( V1; V2 )

The data regarding the purity of the nitrite of the standard solution are, according to the

producer, the following:

NO2- 1002 mg/l

+/- 5 mg/l

and are therefore: 99,5 +/- 0,5 %

As there is no additional information about the uncertainty, but a higher fluctuation margin

can be expected, a rectangular distribution (1/√3) is adopted.

The standard measurement uncertainty of the purity specification for nitrite is:

u(R) = 0,29 %

For the comparison solution 1, 500 µl of the parent solution are dissolved in 500 ml of water.

The following components shall be regarded as uncertainty budgets:

- Purity of the parent solution ( R )

- Pipette ( P) (variable up to 1000 µl)

- Volumetric flask ( M )

After the measurement uncertainty of the standard, respectively parent solution is known, the

volume units pipette and volumetric flask are evaluated. For the pipette, the variation

coefficient of the pipette test according to DIN EN ISO 8655-6 is used. For the volumetric

flask, the printed producer specifications are used. Under the condition of precision in

preparation and regular verifications, extreme values related to the nominal values are hardly

to be expected. The estimation of the standard uncertainty is therefore performed by adopting

a rectangular distribution (1/√6).

The standard measurement uncertainty is:

- for the pipette ( P500 ) u(P) = 0,02 %

- for the volumetric flask ( M500 ) u(M) = 0,03 %

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The combined standard measurement uncertainty for the comparison solution 1 is estimated to

be:

u(V1) = √(R2+P

2+M

2)

u(V1) = 0,29 %

For the comparison solution 2 , 1000 µl of the parent solution are dissolved in 200 ml of

water. The uncertainty budgets shall be calculated as described before.

The standard measurement uncertainty is:

- for the pipette ( P1000 ) u(P) = 0,03 %

- for the volumetric flask ( M200 ) u(M) = 0,07 %

The combined standard measurement uncertainty for the comparison solution 2 is estimated to

be:

u(V2) = √(R2+P

2+M

2)

u(V2) = 0,30 %

From the comparison solutions 1 and 2, the calibration solutions (L) for the calibration curves

are set in 25 ml volumetric flasks. Here, only the volumes of the pipette and the volumetric

flask are decisive. Without taking into consideration the repeated pipettings, a roughly

estimated measurement uncertainty of

ca. u(L) = 0,12 %

has to be presupposed for the calibration solutions.

In the following step, the measurement uncertainty of the calibration curve is estimated by

means of the linearity evaluation. According to a VDI guideline, the calibration curve is not

linear, the use is to be tested explicitly for every use. For the examinations the extinctions

were read off the photometer four times for five concentration stages. The results were

assessed according to ISO 5725-1 by means of the linear model equation. In the linear model

equation, the measurement uncertainty = u(E) is calculated by means of the offset (bias) and

the standard deviation.

The standard measurement uncertainty for the ―large‖ calibration curve is estimated to be:

u(E) = 1,68 %

This value corresponds to 0,177 µg NO2 absolute and is valid for a medium extinction of

0,400 (ca. 10,5 µg NO2). As our measured values are obviously under these testing values

(max. 0,290 extinction), the measurement uncertainty mentioned above should be a maximal

estimation in relation to our work focus. The so-called ―small‖ calibration curve is generally

used for very low NO2 concentrations for the calculation of results. Because of the additional

error possibilities in the range of the lower detection limit, the measurement uncertainty

mentioned above shall be set the same when the small calibration curve is used.

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The observation of the photometer also belonged to the description of the measurement

uncertainty source 1. Here, the producer specifications could be used to the greatest possible

extent for the determination of the measurement uncertainty. Additionally, repeated tests of

linearity were performed by means of a workplace limit value calibration filter set at 433nm.

According to manufacturer information the measurement uncertainty (total) to be envisaged

for the used LKB photometer is approx. u(PH) = 1,0 %. However, tests with the calibration

filter set have shown that the measurement uncertainty of linearity alone must be estimated to

1,25%. If we add components such as: stray light, read off accuracy by murmur,

reproducibility and wave length influence, the measurement uncertainty in laboratory

conditions aggregates to

u(PH) = 1,46 %

In the following, the combined standard measurement uncertainty of the 1st measurement

uncertainty source is calculated and discussed.

u(Q1)Total = √(u(V2)2+u(L)

2+u(E)

2)

u(Q1)Total = 1,71 %

During the assessment of the uncertainty budgets it was observed, that the linearity of the

calibration curve (u(E)=1,68%) delivered the highest individual contribution of the standard

measurement uncertainty. Based on own examinations, the measurement uncertainty of the

photometer shall be estimated to be in the same range. The measurement uncertainty of the

linear calibration function is probably due to error sources of the photometer. Therefore, only

one of the budgets may be taken into consideration during the evaluation.

The frequent use of the Saltzman method leads to the fact that, for the regression calculation

of the calibration curve, we reach a correlation coefficient which is close to 1 and repeatable

(r=0,999). Therefore, we find the linear approach practical and sufficiently secured with the

relatively high measurement uncertainty. The following table 1 offers an overview of the

measurement uncertainties of the individual budgets. The uncertainty of the photometer in

brackets has not been considered in the combined standard measurement uncertainty of the

uncertainty source 1.

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Table 1 Measurement uncertainty budgets of the analytical work stages (calibration curve)

Measurement uncertainty source 2

Reference measurement procedure Saltzman; execution of manual sampling

For the wet-chemical sampling, the following components were to be taken into

consideration:

- Procedure characteristics of the wash bottle operation ( W )

- Volume determination by means of an orifice plate working point ( VS )

For the assessment of the wash bottles (W) in view of the measurement uncertainty budgets:

receiver reaction solution, low pressure in the wash bottles, absorption degree of the nitrite

and repeat determinations, own examinations were available. As reference, the reference

standards used in the framework of the accreditation with corresponding DKD-calibration,

were used for comparison.

After the analyses of comparison measurements, the following standard uncertainties can be

estimated:

- receiver in the wash bottle( WV ) u(WV) = 0,12 %

- low pressure in the wash bottle ( WU ) u(WU) = 0,21 %

- Absorption degree of the wash bottle (WA) u(WA) = 0,80 %

- Averaging at repeat determinations (WD) u(WD) = 0,05 %

The receiver in the wash bottle must correspond to the volumes of the calibration solutions.

The filling takes place with a dispensed, which has been set to the appropriate volume by

means of a balance. Therefore, the measurement takes place at a mass reference standard.

The low pressure measurements are to be determined by several repeats and are to be

connected to the standard air pressure (101.3 kPa). As no extreme values were expected, a

rectangular distribution (1/√3) was adopted.

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We work with only one wash bottle, after each of them has been tested for its absorption

degree. This routinely always happens when there are repairs or new acquisitions. All wash

bottles are labelled so as confusion is impossible. The tests showed that in the second wash

bottle only a calculation value was detected below the lower detection limit. For the

evaluation of the measurement uncertainty, the measured values of the second wash bottle

were quantified as lower detection limit (3 µg/m3). The absorption degree in the first wash

bottle is on average 99,2%.

The measurement of nitrogen dioxide is determined exclusively by repeat determinations.

The results are indicated as average values, which results too in a smaller contribution to

measurement uncertainty.

The combined standard measurement uncertainty for the procedure characteristics of the wash

bottles is estimated to:

u(W) = √(u(WV)2+u(WU)

2+u(WA)

2+u(WD)

2)

u(W) = 0,84 %

As a relative measure, the nitrogen dioxide measurement result comprises not only mass

determination but also volume determination. The last plays an important part in the accuracy

of the results. By changing over from the so-called sampling suitcases customary to the trade

to orifice plate working points, our results improved dramatically. Interlaboratory tests have

confirmed this and have lead to the fact that today only orifice plate working points are used

for volume determination.

For the determination of volume flow (V), the following components are to be taken into

consideration:

- Volume flow of the orifice plates 1 und 2 ( VB )

- Temperature measurement on the orifice plates 1 und 2 ( T )

- Air pressure measurements ( LD )

- Time measurements ( Z )

The measurement of volume flow was performed with a reference volume in relation to time

measurement. The error of the reference volume was indicated at 0,2%. Between the

manufacturer information and own examinations results a measurement uncertainty related to

the measure of u(VB) = 0,03 to 0,08 %.

The temperature at the orifice plates was compared to the temperature reference standard. A

measurement uncertainty of u(T) = 0,56 % resulted in relation with an average working

temperature of 23°C.

The deviation of the air pressure measurement is, according to the manufacturer

101.3 +/- 0.11 kPa, which corresponds to a relative standard measurement uncertainty of u(LD)

= 0,06 %.

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A measurement uncertainty of time measurement was not possible, as a measurement error

would always fall to the manual time comparison on automates interval timing. For this

reason, the measurement uncertainty is estimated to ca. u(Z) = 0,02 %.

The combined standard measurement uncertainty for the volume flow determination is

estimated to:

u(VS) = √(u(VB)2+u(T)

2+u(LD)

2+u(z)

2)

u(VS) = 0,57 %

In the following, the combined standard measurement uncertainty of the second measurement

uncertainty source is calculated and discussed.

u(Q2)Total = √(u(W)2+u(VS)

2)

u(Q2)Total = 1,01 %

The uncertainty budgets of mass determination and of volume determination constitute

approximately equal parts of the relative measured value of nitrogen dioxide. In the sampling

part mass, the absorption degree of the wash bottle mathematically makes out the highest

uncertainty budget of the total result. Because always less then the lower detection limit is

found in the second bottle, the sampling can continue with only one bottle is the estimated

uncertainty is taken into consideration. The rest of the uncertainty budgets play a secondary

role.

In volume measurement, the temperature influence brings with it the highest measurement

uncertainty. This is important in so far as we can observe a great dynamic of temperature in

every day of work, especially in the weather conditions in summer. The volume flow of the

orifice plates only shows low measurement uncertainty. As volume flows grow in time, the

orifice plates are calibrated before each sampling. Measurement uncertainties of air pressure

measurements and time measurement are almost unnoticeable in the total result.

In table 2 an overview of the measurement uncertainties of the individual uncertainty budget

is presented.

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Table 2 Measurement uncertainty budgets of manual sampling

Measurement uncertainty source 3

Transfer gas standard CSI 1700; Preparation of test gas source for the measure nitrogen

dioxide.

The transfer gas standard CSI 1700 (T) is built out of a volume thinner unit and a certified test

gas mixture in a pressure gas bottle. The NO gas mixtures (40 ppm NO in nitrogen) are

bought. The relative measurement uncertainty on the analysis certificate of class 1 test gases

(DIN51895) is indicated to be +/- 2%. For the preparation of transfer gas standards, the

volume flows of the thinning unit are checked and the NO gas mixture is certified in-house by

means of gas phase titration and the reference measurement procedure. The course of action is

shown in picture 1.

For the determination of the measurement uncertainty of the transfer gas standard, the

following steps have to be taken into consideration:

- Volume flows of the thinning unit ( TB, TG )

- Repeatability of thinning settings ( TVR )

- Linearity of thinning steps ( TL )

- Repeatability of the gas phase titration ( TGR )

At the determination of volume flows for the admixture of the NO gas mixture as well as for

the basic gas, a soap bubble flow meter and a volume meter (see volume flow determination

for orifice plates) are used. The measurement uncertainty of the admixture thinning is

estimated as follows:

uTB(10 ml) = 0,22 %

uTB(25 ml) = 0,25 %

The test volumes are used in a ratio of 2/3, so that a weighted measurement uncertainty of the

admixture of

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u(TB) = 0,24 % results.

The basic gas volume flows are used in the same amounts as follows:

uTG(4000ml) = 0,10 %

uTG(5000ml) = 0,12 %

The standard measurement uncertainty of the basic gas volume flow amounts to:

u(TG) = 0,15 %

It is not the absolute value of the volume flows which are of the highest priority in the use of

transfer gas standards, but the repeatability of the exact mechanical settings. Therefore, the

measurement uncertainty of the thinning stages takes into consideration the mobile use; it is:

u(TVR) = 0,28 %

Because of the variable setting possibilities of the thinning stages, the linearity evaluation

had to be performed. To this purpose, up to five repeated series of the thinning stages were

acquired. The measurement uncertainty of linearity was generated by the ratio between the

measurement uncertainties of the thinning stages. In the comparison of the models according

to ISO 5725-1 and Nordtest, coinciding results were obtained for the determination of the

measurement uncertainty of linear equations. Our test obtained a measurement uncertainty of:

u(L) = 0,51 %

The NO/NOX-chemiluminescence measurement device is calibrated with NO test gases. As

with the reference measurement procedure only the nitrogen dioxide can be determined, the

NO test gases have to be oxidized quantitatively to NO2 test gas. This is done by means of gas

phase titration, a step of the procedure which is a permanent feature of the transfer gas

standard. The measurement uncertainty of the repeated setting of a defined ozone lamp

current was to be determined.

By a comparison measurement performed 15 times, a measurement uncertainty at the

repeating of the titration of:

u(TGR) = 1,40 % resulted.

In the following the combined standard measurement uncertainty of the mechanical part of the

transfer gas standard CSI 1700 is calculated and discussed:

u(Q3)Total = √(u(TVR)2+u(TL)

2+u(TGR)

2)

u(Q3)Total = 1,52 %

The evaluation of the measurement uncertainty of the transfer gas standard had to take place

with the aid of volume reference standards as well as of a NO/NOX measurement device. As

the individual steps partially cannot be performed independently of each other, the results

were used without corrections for the calculation of the measurement uncertainties. For

instance, in the test result of the measurement device during gas phase titration, the

measurement error of the converter incurs. The repeat test of the mechanical setting of the

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ozone lamp could therefore contain a contribution of the measurement device at the

measurement uncertainty estimation. Here, the measurement uncertainties of the measure NO2

are probably overestimated. The following table offers an overview of the individual budgets

at the examination of the transfer gas standard.

Table 3 measurement uncertainty budgets of mechanical setting possibilities of the transfer

gas standard CSI 1700

Measurement uncertainty source 4

NO/NOX-chemiluminescence measurement device in the continuous monitoring network

service.

During the operation of the nitrogen dioxide testing measurements (M), according to the

guideline DIN EN 14211:2005, the following tests are to be arranged, besides the specific

procedure parameters confirmed during the type approval test for suitability evaluation:

- 25-hour function controls ( MF )

- Quarterly control calibrations with test gas ( MK )

- Converter efficiency coefficient verifications ( MKW)

- Data validations ( MD )

For the estimation of the measurement uncertainty, manufacturer‘s information, suitability

test results and own examinations from the monitoring network service were used. Validated

comparative results from other monitoring networks could not be used due to the different

handling of the technical accessories, as well as due to the handling of raw data.

The device-specific data of the producer and those of suitability tests are only covered

separately when there is relevant influence upon the measure NO2. Otherwise, they are used as

a composite result for the calculation of the total measurement uncertainty. The components

that are important are those which can be influenced by the monitoring network operation and

can change under certain circumstances.

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For the calculation of the measurement uncertainty for the function test the results of the 25-

hour test gas overplug for a month were brought up. For the corresponding concentration

values zero and NO2 measured value, the bias was determined. As extreme values can be

expected, a rectangular distribution (1/√3) was adopted, and the part with the relation to the

yearly average value (1/√12) was used for the calculation. In the daily work control deviations

under the threshold of 7% are tolerated. Higher deviations lead to an immediate verification of

the whole measurement site.

The standard measurement uncertainty of the function test is of:

u(MF) = 0,93 %

For the control calibration of the measurement devices, the transfer gas standard is used with

that measurement uncertainty which has been determined as uncertainty budgets of the

uncertainty sources Q1 - Q3. The standard measurement uncertainty must be fully estimated,

as the calibration procedure is timely independent and always constitutes the base for a

completely new calibration function. The transfer of the test gas standard for the calibration

with the transfer gas standard therefore determines the highest measurement uncertainty for

the measure NO2 in the area of the continuous monitoring network service.

The standard measurement uncertainty of the test gas concentration is of:

u(MK) = 2,50 %

At an efficiency coefficient of ≤ 97 % the converter is renewed without exception and the

measurement device is then tested. The measurement uncertainty of the converter is

performed with 97 of one hundred as a maximal estimation. A converter efficiency

coefficient between 97,1 and 100% will not be taken into consideration for the result of the

measure NO2. The calculation of the measurement uncertainty is performed by means of the

bias, as described for the function control. There is just a different reference time interval in

view of the proportional consideration of the yearly average value (1/√92). The measurement

uncertainty calculated with own means, which aligns with the data from the suitability test,

amounts to:

u(MKW) = 0,31 %

The measurement uncertainty on data validation was calculated on the basis of the EN ISO

20988:2004. The results on the measurement device were defined as reference values and the

results in the network centre were defined as test values. A standard measurement uncertainty

of u(MD) = 0,06 % resulted, which has no importance for the total result.

In the following, the measurement uncertainties from information of the device manufacturer

and of the suitability evaluation report are listed and presented taken together:

Linearity u = 0,58 %

Point zero murmur u = 0,69 %

Sensitivity murmur u = 0,29 %

Cross sensitivities u = 0,29 %

Temperature dependency (Con.) u = 0,17 %

Drift u = 0,74 %

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Reproducibility u = 0,43 %

Accuracy u = 0,29 %

u(specifications) = √(0,582+0,69

2+0,29

2+0,29

2+0,17

2+0,74

2+0,43

2+0,29

2)

u(specifications) = 1,35 %

In the following, the combined standard measurement uncertainty of the measurement device

is calculated and discussed:

u(Q4)Total = √(u(MF)2+u(MKW)

2+u(MD)

2+u(Angaben)

2)

u(Q4)Total = 1,67 %

In table 4 the measurement uncertainty budgets are presented as an overview.

Table 4 measurement uncertainty budgets of the NO/NOX-Chemiluminescence measurement

device

For the estimation of the measurement uncertainty of the measurement device, the calibration

with the transfer gas standard plays a decisive part. Therefore, for the practical operations it is

of utmost importance that the measure NO2 is transferred as well as possible from the transfer

gas standard to the measurement device during calibration. In the past, it could be shown for

many comparison measurements that especially systematic errors during calibration lead to

the highest uncertainties.

The estimation of the measurement device parameters is difficult in so far as it cannot be

estimated to which extent measurement uncertainties overlap or are taken into consideration

too low. Therefore it is important to realise which components are dependent of each other

and when corrections should be made. In the case of a possible overestimation, for instance

for the repeatability of the gas phase titration, direct corrections have a larger effect upon the

total result.

The second largest contribution to the combined standard measurement uncertainty is given

by the 25-hour function control. Because of the way we proceed, it can also be the case that

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for instance temperature or pressure dependencies as well as other components are taken into

consideration twice in this contribution.

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6. Calculation of the combined measurement uncertainty After the estimation of the individual budget of the uncertainty sources, the combined

standard measurement uncertainty is calculated. As for the uncertainty sources Q1-Q4 the

group-specific budgets have already been summarised, in the last step the combined standard

measurement uncertainty for the measure NO2 is subsequently calculated:

uNO2 = √(uQ12+uQ2

2+uQ3

2+uQ4

2)

uNO2 = √(1,712+1,01

2+1,52

2+1,67

2)

uNO2 = 3,01 %

After completion of the examinations, the combined standard measurement uncertainty for the

measure NO2is estimated to uNO2 = 3,01 %. Thanks to the specific procedure, the uncertainty

can be directly transferred to the air quality values in the network.

This is because in the framework of the operations in the test gas lab, the same measurement

devices as the ones operated in the monitoring network have been included in the tests

respectively.

7. Expanded measurement uncertainty With the expanded measurement uncertainty an interval is presented, in which the estimated

proportion percentage of the measured values, which can be rationally ascribed to the measure

NO2, find themselves. First, the expansion factor has to be determined, while observing

certain criteria. For most uses, the expansion factor of k=2 corresponding to a confidence

level of approx. 95% is recommended.

At the determination of the uncertainty budgets for the measure NO2, the statistical

observations could usually be secured by a high number of measured values. For the linearity

evaluation, for instance the calibration curve or the calibration function of the measurement

device, as well as for the reproducibility of variable adjustments of the transfer gas standard,

substantial series of measurement were available. These results, with the proportionally

highest individual contributions to the measurement uncertainty are to be ascribed to rather

accidental effects. However, due to the large number of inquiries they are viewed as

sufficiently accurate. The expansion factor k=2 is also accepted by us, only as it is

presupposed that the test values of the repeated measurement are distributed normally.

u(95%) = uNO2 * k (k=2)

u(95%) = 3,01 * 2

u(95%) = 6,02 %

The expanded measurement uncertainty of the measure NO2 is estimated to ca. 6 %

In annex 1 the uncertainty budgets corresponding to the cause and effect diagram are rendered

with the underlying connections.

8. Documentation In this SOP only a summary of the calculated uncertainty budgets is presented. Because of the

different dimensions of the components, the measurement uncertainty is consistently updated

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in percentages. The method of the course of action is partly rendered in the text, or reference

is made to the literature. The calculations have been performed in Excel worksheets with the

purpose to, on the one hand perform new evaluations and on the other hand to be able to

evaluate further components in view of comparable measurement uncertainty sources by

means of the schemes.

The three underlying Excel worksheets are:

o Measurement uncertainty-CSI-1.xls

o Measurement uncertainty-CSI-2.xls

o Measurement uncertainty-budget overview.xls

The worksheets are appropriately secured and are additionally stored on carriers.

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9. Responsibility Chief of calibration lab

10. Literature

GUM – Guide to the expression of uncertainty in measurement

DIN – Deutsches Institut für Normung e.V. - Translation 1995

ISO 5725-1 – Accuracy (trueness and precision) of measurement methods and measurement

results

DIN V EN V 13005 Edition 1999-06 – Guide to the specification of uncertainty in

measurement

EURACHEM-/-CITAC – Guide: Determination of measurement uncertainty in analytical

measurements

NORDTEST Report TR 537 – Handbook for calculation of measurement uncertainty in

environmental laboratories 2003-05

DIN EN ISO 20988:2004 Air Quality - Guide to estimating measurement uncertainty

DIN EN ISO 14956:2003 Air Quality — Evaluation of the Suitability of a Measurement

Procedure by Comparison with a Required Measurement Uncertainty

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11 Annex

Annex 1 Measurement uncertainty - budget overview

Illustration of uncertainty sources with numerically evaluated uncertainty budgets. The

proportion of the expanded measurement uncertainty (k=2) of the measure NO2 for the

transfer gas standard CSI 1700 is ca. 5 %. The expanded measurement uncertainty of the

measure NO2 at continuously generated measurement data in the air quality monitoring

network is estimated to about 6%.

Components to be used

Nitrite standard solution

Traceable to SRM of NIST 500 ml

NaNO2 in H2O - 1000 mg/l NO2- ß(NO2) = 1002 +/- 5 mg/l

MERCK Nr. 1.19899.0500

Pipettes

Producer: Eppendorf

- No.: 246465 – 1000 µl (variable) tested according to DIN EN ISO 8655-6 12/2002

- No.: 114350 – 1000 µl (fix) tested according to DIN EN ISO 8655-6 12/2002

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Volumetric flask

Producer: Brand

- 500 +/- 0,25 ml – In 20 °C

- 200 +/- 0,15 ml – In 20 °C

- 25 +/- 0,04 ml – In 20 °C

Photometer

Producer: LKB Biochrom Ltd. England

Model: Ultrospec II; product no: 05647

Gas sampling equipment with orifice plates

Self-made

- Double sampling

- Orifice plates out of platinum/iridium Ø 300 µm

- Built-in elements for temperature measurement

Temperature reference standard

Producer: testo AG; Type: 0560 7206; product no: 00923572; DKD calibrated 01/04

Time reference standard

Producer: Hanhart GmbH & Co.KG; Model: Profil 1; Serial-No.: 2394; calibrated 01/04

Air pressure measurement device

Aneroid barometer in casket

Producer: Lambrecht, Göttingen

BROOKS Vol-U-Meter

Distributor: Brooks Instrument B.V. – The Netherlands

Test volume 3500 ml

Transfer gas standard

Producer: Columbia Scientific Industries Corporation – USA

―GAS PHASE TITRATION CALIBRATOR‖ – Model 1700

NO-gas mixture in pressure gas bottle of 2 litres

Supplier: Linde AG – Spezialgase Produktion – Carl von Linde Straße 25,

85716 Unterschleißheim

Nitrogen monoxide in nitrogen 40 ppm +/- 2 % relative measurement uncertainty

Analysis certificate for test gases class 1 – according to DIN 51895

Content 300 l; Stability 12 month

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NO/NOX-Chemiluminescence measurement device

Model: MLU 200A

Producer: Advanced Pollution Instrumentation Inc.

8815 Production Avenue, San Diego, CA 92121, USA

Measurement range: 1000 ppb – 1913 µg/m3

Guidelines

Tasks of the Data Centre of an

Air Quality Monitoring Network

Recommendations, Regulations and Examples for:

The Validation of Measurement Data

The Calculation of Parameter

The Reporting and the Data Transfer

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I. Recommendations on Data Validation in Air Quality Monitoring Networks

II. Recommendations on the Calculation of aggregated Data and statistical

Parameters

III. Annexes – Examples for procedure instructions for data centres in Austrian

and German Air Quality Monitoring Networks

III.A1 Automatic validation of air quality data

III.A2 Control and release of air quality data

III.A3 Information of the public on air quality

III.A4 Reports, statements, publications

III.A5 Handling of external requests on air quality data

The main part of a quality management in an air quality monitoring network is the

regulated and documented processing of the measured data. This includes:

- the data generation on site with continuous and discontinuous measurements,

- the data capture and processing on site,

- the data transfer to the data centre of the monitoring network,

- the validation and possible correction of the data,

- the prompt information of the public,

- the reporting,

- the data transfer to externals.

In the here presented guidelines, recommendations and regulations basing on the

CAFE Directive 2008/50/EC and which are in this form applied in most of the

European monitoring networks, are documented. In the five appendices work

instructions of the AQ-monitoring networks of Austria and Germany are given. These

describe the necessary works of the data centre according to the procedure

instructions. These instructions are specific for the relevant monitoring network and

shall therefore only be understood as examples for regulation possibilities. The

examples originate from accredited monitoring networks and represent an important

part of the technical regulation in the field of the quality management system.

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Contents

I. Recommendations on Data Validation in Air Quality Monitoring Networks 221

1. Rules and recommendations concerning data validation ......................... 221 1.1. Introduction .............................................................................................. 222 1.2. Definitions ................................................................................................ 222

1.2.1. Measuring device ...................................................................................................... 222 1.2.2. Calibration ................................................................................................................. 222 1.2.3. Baseline or zero line .................................................................................................. 222 1.2.4. Qualified person - Authorised .................................................................................... 222 1.2.5. Quality code ............................................................................................................... 222 1.2.6. Raw data ................................................................................................................... 223 1.2.7. Validated data ............................................................................................................ 223 1.2.8. Aggregated data ........................................................................................................ 223 1.2.9. Prevalidation .............................................................................................................. 223 1.2.10. Data action ................................................................................................................ 223 1.2.11. Invalidation threshold................................................................................................. 223 1.2.12. Maxi threshold / detection limit .................................................................................. 223 1.2.13. Data validity ............................................................................................................... 224

1.3. Validation of AQ data ............................................................................... 224 1.3.1. Prerequisites for validation ........................................................................................ 224 1.3.1.1. The qualified person‘s general knowledge ................................................................ 224 1.3.1.2. General and technical analysis instruments .............................................................. 224 1.3.1.3. Additional parameters................................................................................................ 225 1.3.2. Validation stages ....................................................................................................... 225 1.3.2.1. Automatic prevalidation: the system process ............................................................ 225 1.3.2.2. Validation by the qualified person: the expert process .............................................. 226 1.3.3. Organisation of the validation .................................................................................... 226 1.3.3.1. The fast/temporary mode .......................................................................................... 226 1.3.3.2. The normal/definitive mode ....................................................................................... 227 1.3.3.3. The validation periodicity (daily, monthly, yearly) ...................................................... 227 1.3.4. Validation rules .......................................................................................................... 227 1.3.4.1. A few validation rules common to all pollutants ........................................................ 227 1.3.4.2. Sulphur dioxide (SO2) ................................................................................................ 228 1.3.4.3. Ozone (O3) ................................................................................................................. 228 1.3.4.4. Nitrogen oxides (NO and NO2) .................................................................................. 229 1.3.4.5. Particulates (PM10, PM2.5) .......................................................................................... 230 1.3.4.6. Carbon monoxide (CO) ............................................................................................. 230 1.3.4.7. BTX (automatic device) ............................................................................................. 230 1.3.4.8. Wind direction ............................................................................................................ 231 1.3.4.9. Wind speed ................................................................................................................ 231 1.3.4.10. Temperature .......................................................................................................... 231 1.3.4.11. Relative humidity ................................................................................................... 231 1.3.4.12. Sunshine ............................................................................................................... 231 1.3.4.13. Pressure ................................................................................................................ 231 1.3.5. Traceability of the validation ...................................................................................... 231

1.4. Further handling of the validated data ...................................................... 232 1.4.1. Data processing ......................................................................................................... 232 1.4.2. Data interpretation ..................................................................................................... 233

Annex 1: Examples for detection limits (depending on the operated measuring devices and the test results of these analysers) .....................................................................................234

Annex 2: Table of minimum validation criteria common to all pollutants .............................234

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II. Recommendations on the Calculations of aggregated Data and statistical Parameters ............................................................................................................ 236

1. Objective and purpose .................................................................................. 236

2. Scope .............................................................................................................. 236

3. Definitions and Abbreviations ...................................................................... 236

4. Definition of the procedures ......................................................................... 237 4.1. Calculation of parameters ........................................................................ 237 4.2. Conversion factors ................................................................................... 239 4.3. Availability (Data Capture) ........................................................................ 240 4.4. Realisation ............................................................................................... 240 4.5. Data correction ......................................................................................... 241 4.6. Rounding / Evaluation .............................................................................. 243

4.6.1. Rounding ................................................................................................................... 243 4.6.2. Examination of the limit value exceedance ............................................................... 243

III. Annexes – Examples for procedure instructions for data centres in .... 245

Austrian and German Air Quality Monitoring Networks .................................... 245 III.A1: Automatic Validation of Air Quality Data ................................................... 245

1. Purpose .......................................................................................................... 245

2. Scope .............................................................................................................. 245

3. Terms/Abbreviations ..................................................................................... 245

4. Procedure Description .................................................................................. 245 4.1. Basic description ...................................................................................... 245 4.2. Parameterisation of the automatic network centre validation ................... 247 4.3. Control of the automatic network centre validation ................................... 247

5. Responsibilities ............................................................................................. 248

6. Further Applicable Documents .................................................................... 248 III.A2: Control and release of Air Quality Data .................................................... 249

1. Purpose .......................................................................................................... 249

2. Scope .............................................................................................................. 249

3. Concepts / Abbreviations ............................................................................. 249

4. Description ..................................................................................................... 250 4.1. Data control – Online acquisition .............................................................. 250

4.1.1. Daily data control – manual plausibility check ........................................................... 250 4.1.2. Monthly data control .................................................................................................. 253 4.1.3. Data control after calibration ..................................................................................... 255

4.2. Data control – Gravimetric determination of the concentration of the PM fraction ................................................................................................................ 256

4.2.1. First plausibility check ................................................................................................ 256 4.2.2. Monthly data control .................................................................................................. 257 4.2.3. Data control after calibration ..................................................................................... 257

5. Data control before the annual report ......................................................... 257

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6. Documentation and storage ......................................................................... 258 6.1. Daily data control ...................................................................................... 258 6.2. Monthly data control ................................................................................. 258 6.3. Control after calibration ............................................................................ 258

7. Data provision ............................................................................................... 259 7.1. Publication of data .................................................................................... 259 7.2. Data provision on request ........................................................................ 259

8. Further applicable documents ..................................................................... 259 III.A3: Information of the Public on Air Quality Data ............................................ 260

1. Purpose .......................................................................................................... 260

2. Scope .............................................................................................................. 260

3. Responsibilities / Definitions ....................................................................... 260

4. Description of basic procedures .................................................................. 260

5. Information regarding measured air quality data ....................................... 261 5.1. Data flow in the monitoring network centre .............................................. 261 5.2. Content and timelines of information ........................................................ 261 5.3. Measured data and information to be made available within a short period of time 263

5.3.1. Hourly data ................................................................................................................ 263 5.3.2. Daily report ................................................................................................................ 264 5.3.3. Exceedance of limit values and of information/alert thresholds ................................ 264 5.3.4. Timely public information regarding the air pollutant ozone ...................................... 264

5.4. Information to be provided periodically or when required ......................... 268 5.4.1. Monthly report ............................................................................................................ 269 5.4.2. Annual report ............................................................................................................. 269 5.4.3. Special reports ........................................................................................................... 269

6. Other information for the public................................................................... 269 6.1. Air quality monitoring concept .................................................................. 270

6.1.1. Monitoring network structure ..................................................................................... 270 6.1.2. Monitoring station documentation ............................................................................. 270 6.1.3. Measurement methodology and procedures ............................................................. 270

6.2. Evaluation standards ................................................................................ 271 6.3. Formation and effects of air pollutants ..................................................... 271 6.4. Plans and Programmes ............................................................................ 271

7. References ..................................................................................................... 271 III.A4: Reports, Statements, Publications ............................................................ 273

1. Purpose .......................................................................................................... 273

2. Scope .............................................................................................................. 273

3. Description ..................................................................................................... 273 3.1. Preparation of reports, statements, and data publication ......................... 273 3.2. Reports, statements and data publication ................................................ 274

3.2.1. Reports on air quality ................................................................................................. 274 3.2.2. Expert opinions and statements ................................................................................ 274 3.2.2.1. The standard structure of expert opinions and advisory opinions ............................. 274 3.2.2.2. Verification and release ............................................................................................. 275 3.2.2.3. Signature regulations................................................................................................. 275 3.2.3. Internal reports .......................................................................................................... 275

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3.2.4. Data publication ......................................................................................................... 276 3.2.5. Data provision on demand ........................................................................................ 276

III.A5: Handling of External Requests on Air Quality Data .................................. 278

1. Purpose .......................................................................................................... 278

2. Scope .............................................................................................................. 278

3. Procedure description .................................................................................. 278 3.1. General provisions ................................................................................... 278 3.2. Verification of requirements for accepting the request ............................. 278 3.3. Application processing (data provision) .................................................... 279

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I. Recommendations on Data Validation in Air Quality Monitoring Networks

1. Rules and recommendations concerning data validation

Data validation is at the heart of the activities carried out by the data centre of each

Air Quality Monitoring Network. As experience was acquired by the different

European networks, more or less formalised validation methods have been worked

out and used. It is necessary to harmonise these methods.

The goal is to work out general recommendations and validation rules in order to

constitute a reference. This document mainly deals with the validation of raw data

and the calculation of statistical parameters.

The basic premise serving as the guiding principle in writing this chapter was: ―the

validation of air quality data is composed of a set of actions carried out by

experienced persons in the field of air quality monitoring and who have the possibility

of refining their expertise during certain of these actions by using instruments helpful

in decision-making.‖

The recommendations chapter distinguishes the automatic prevalidation systems

from the expert process of data validation.

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1.1. Introduction

The first goal of data validation is to guarantee a certain quality level for the

information distributed to the public.

AQ data validation makes it possible to give useable validated data for all

subsequent use (e.g. processing, interpretation) while improving the technical follow-

up of the measuring device (e.g. maintenance, data action, equipment management).

The daily, monthly and yearly validations make it possible to give processed, even

interpreted, data for subsequent distribution (general public, the media, the

authorities, etc.).

1.2. Definitions

1.2.1. Measuring device

This term includes automatic gas or particulate analysers as well as meteorological

sensors.

1.2.2. Calibration

Comparison of the measuring device response to a known gas concentration with a

known uncertainty.

1.2.3. Baseline or zero line

Response of the measuring device in the absence of pollutants (i. e. zero gas)

1.2.4. Qualified person - Authorised

Qualified person is an experienced person possessing specific know-how and

general knowledge required for carrying out validation operations. The qualified

person may be authorised to carry out validation operations in one or both of the

following fields:

• Technical authorisation: usually but not exclusively this means the staff

responsible for the technical operation of the network.

• Environmental survey authorisation: usually but not exclusively this means the

staff responsible for data analysis and assessment.

1.2.5. Quality code

This code depends on the used processing system and should be described and

added later.

Remarks:

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Information distributed in near-real time (via Internet, teletext) - except those data that

lead to triggering off information thresholds or warnings –are recommended to be

defined as preliminary.

1.2.6. Raw data

Raw data are the aggregated values of instantaneous measurements (generally the

mean)

1.2.7. Validated data

Validated data are checked and possibly modified by qualified persons during the

expert process of validation. After that they are considered as distributable.

1.2.8. Aggregated data

Aggregated data are data obtained after processing of validated data.

1.2.9. Prevalidation

Data checking according to predefined criteria (data capture, negative values,

constant values, anomaly). These acts can be carried out at the different levels of the

measurement chain (measuring device, acquisition system and/or central station)

and lead to a data action on the data‘s value and/or the quality code.

1.2.10. Data action

An act that consists in invalidating or correcting data.

• Invalidation: it consists in deducing that a status or a data are erroneous and

in assigning it (them) the corresponding quality code.

• Correction: it consists in modifying the value of data or their quality code

(given present-day knowledge, it is wise to be careful in modifying the value of

a status).

1.2.11. Invalidation threshold

The invalidation threshold is the calibration deviation (zero and span point) beyond

which the data and the status must be invalidated.

1.2.12. Maxi threshold / detection limit

These terms indicate the upper and lower limit of data validity.

• Detection limit: The smallest concentration of a measurand that can be reliably

detected by a specific measurement process, calculated e.g. according to

prEN 14212:2010 (E) as 3,3x(sz/B), where sz is the standard deviation of

instrument response at zero concentration and B is the slope of calibration

function (see examples in annex 1).

• Maxi threshold: the maximum value above that the measuring device cannot

detect (it is attached to the measuring range).

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1.2.13. Data validity

A status is considered valid if at least 75 per cent of its constituent elements are

valid.

Example:

Presently the standard time period is an hour (mean of the measurements over 60

minutes), the data system considers that the hourly status is valid if 75% of the

measurements are valid, for example 45 minute values must be available.

1.3. Validation of AQ data

1.3.1. Prerequisites for validation

Raw data can only be validated by a qualified person. To facilitate this validation, it is

advisable on the one hand to implement instruments beforehand and on the other to

have certain complementary parameters during the different stages of the validation.

1.3.1.1. The qualified person’s general knowledge

• Knowledge of air quality metrology (e.g., the validation of NO2 after NO).

• Knowledge of site typology and station classification.

• Climatology: certain climatic phenomena specific to a region might influence

the development of pollutants (e.g., thermal breezes, predominant winds, the

foehn effect, the acceleration of wind by the venturi effect, temperature

inversions,…).

• Geographical conditions: physical relief, the proximity of the sea, altitude and

geographic configuration in a general way can explain certain developments in

concentration profiles.

• Knowledge of atmospheric chemistry (kinetics, reactions, emissions, …).

• Knowledge of potential emitters.

• Data background: background knowledge (especially past records) makes it

possible to provide additional information for assessing situations.

1.3.1.2. General and technical analysis instruments

• Programming significant statistical values: data capture, daily means, standard

deviations, hourly maxima, hourly minima, etc.

• Threshold parameterisation: threshold configuration makes it possible to draw

the validation operator‘s attention to certain data. The thresholds that can

especially be configured are:

the guide and limit values, warning levels of national, local and

European regulations for each type of pollutant; the detection limit and

maxi thresholds defined per pollutant (a list of detection limits and maxi

thresholds should be elaborated);

the invalidation thresholds(to be stipulated according to the European

Standards EN)

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the minimal and maximal values tabulated as a function of the site and

the pollutant (possibly linked with historical values).

• Programming an automatic prevalidation: it can be done on the measuring

device, the station computer or the data centre (an automatic data filtering

software).

• Graphic validation software: this instrument makes it possible to assess the

development of concentration curves in more detail in relation to table

analysis. This in particular makes it possible to:

compare the pollutants of different monitoring stations on the same

graph;

compare the evolution of the pollutants at the same station;

compare pollutants with meteorological parameters (wind speed, wind

direction, temperature, etc.).

• This software can also ensure:

the highlighting of the values exceeding the calibrating deviations;

the highlighting of values exceeding the regulatory thresholds.

• Computer Assisted Maintenance Management or technical recordings, life-

expectancy cards for the measuring devices: makes it possible to know the

nature of the maintenance operations and to determine if an operation might

have an incidence on the data.

• special validation aid software

1.3.1.3. Additional parameters

• Meteorological parameters (data from the network and/or bulletins of the

National Meteo Service): wind speed and direction, pressure, sunshine-time,

temperature, rainfall, hygrometry, cloud cover, ..., information used to explain

pollutant evolution profiles.

• Time and event parameters: are also to be considered in the validation

process: day of the week, the weekend, holidays, seasons, the different

events likely to influence the evolution of pollutant concentrations.

• Previous validation reports: with a view to checking the measurements that

have previously posed problems.

1.3.2. Validation stages

1.3.2.1. Automatic prevalidation: the system process

After obtaining data, the automatic prevalidation of data can intervene at the different

levels of the measurement chain: the measuring device, the station computer or the

data centre.

• On the measuring device level: the value transmitted to the station computer is

accompanied by a characterisation of its condition (valid, faulty). This

characterisation is a prevalidation of the value that will be considered by the

station computer for aggregating the data.

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• On the station computer level: the construction of the data goes with marking

the value by a quality code that is characteristic of its condition. The

assignment of a quality code to the measured value ensures this

prevalidation‘s traceability.

1.3.2.2. Validation by the qualified person: the expert process

The validation process by a qualified person has two mandatory stages:

• technical validation

• environmental-survey validation

The technical validation mainly consists of examining the conformity of the answer of

the measurement system process, acquisition and the constitution of data into a

database: the background of the intervening events (mal functions, threshold

exceedance, …), calibration information and information on the physical maintenance

operations and so on.

Environmental-survey validation consists of cross-sectional analyses on the data

obtained, i.e. the examination of the relevance and consistency of the data (time,

spatial, physical-chemical, the suitability to the meteorological conditions and so on).

1.3.3. Organisation of the validation

In the expert process of validation it is recommended to distinguish between two

validation modes:

• fast-temporary mode

• the normal mode

The main actions are:

• the invalidation of data below the negative detection limit and above maxi

thresholds;

• the invalidation of data whose deviations of function check and calibration are

greater than the respective invalidation thresholds stipulated in the European

Standards EN;

1.3.3.1. The fast/temporary mode

For the fast/temporary mode the validation process requires prompt execution. In this

case a process of limited examination of the data is undertaken according to the two

previously defined stages:

• a technical examination

• an environmental-survey examination

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At the end of this limited examination the data are distributable. Comments can

accompany the data, specifying that they are being published on a temporary basis

and are thus apt to be modified later.

The fast/temporary mode covers situations where the timeframe or the availability of

qualified persons requires a more limited consideration of the validation criteria.

Note that the fast/temporary mode is transitory. As such, the same data later and

mandatory undergo a full validation process.

1.3.3.2. The normal/definitive mode

For the normal/definitive mode, the full data validation process is carried out in

accordance with the two stages defined above:

• the technical validation

• the environmental-survey validation

The normal/definitive mode corresponds to situations where the time-frames and the

qualified persons allow for a full consideration of the validation criteria.

The validation criteria table for all pollutants (annex 2) points up the minimum criteria

to be adhered to for this full validation.

1.3.3.3. The validation periodicity (daily, monthly, yearly)

To ensure a regular follow-up of the air quality data, it is recommended to carry out

the fast/temporary data validation every day morning and in case of special pollution

situations. The normal validation should be done every working day.

For regular, daily follow-up it is necessary to do a monthly check so as to have a

broader view of the data and to take possible periodical phenomena into account.

The final data validation is done after the end of the calendar year and the basis for

the annual reporting.

1.3.4. Validation rules

The following rules give the main criteria to be considered for validating AQ data.

They are given here as a list without hierarchical criteria, and they are used like a

‗tool box‘ that can be used during validation (the list of validation criteria for all

pollutants is not exhaustive and is likely to be added to). A summary table of the

minimum criteria is given in annex 2.

1.3.4.1. A few validation rules common to all pollutants

• Accounting for the present state of the network:

- check data acquisition;

- visualisation of the alarms of the measuring devices.

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• Examination of the assessment of the foregoing maintenance operations:

- accounting for the maintenance planning;

- accounting for the dysfunctions;

- accounting for the specific technical criteria for each measuring device.

• Examination of the responses of the measuring devices to automatic checking

operations of calibration:

the study of exceedances of fixed tolerances.

• Examination of exceedances of programmed values:

- detection limits and maxi thresholds;

- guide values, limits and warning thresholds.

• Examination of previous validation reports.

• Study of the relevance of the data:

- the detection of outliers;

- standard profiles research.

• Study of the data‘s spatial consistency:

the comparison of evolution profiles between geographically close stations and

of the same type.

• Study of the data‘s temporal consistency:

- the examination of typical profiles (e.g. day, week, weekend, season,

etc.);

- accounting for event-like parameters (e.g. demonstrations).

• Physical-chemical consistency of the data:

- checking the correlation or the anti-correlation between pollutants;

- assessment of the recorded concentration levels.

• Suitability of the meteorological conditions: wind, temperature, sunshine,

temperature inversions, rainfall.

• Use of knowledge and accumulated experience: habitual behaviour, local

phenomena when faced with difficulties of judgement for one-off events.

To refine the validation rules that are common to all pollutants, the following specific

rules, established pollutant by pollutant, can be used.

1.3.4.2. Sulphur dioxide (SO2)

• Comparison of industrial stations located in a same geographic area.

• Comparison in certain cases (industrial smoke plumes) with NO and PM.

• Taking into account special house heating situations.

• Survey of the wind speed and direction for identifying the source of a plume

originating from a known fixed source or the possible transport of polluted air

masses into the region.

1.3.4.3. Ozone (O3)

• Several station groups can be defined mainly as a function of the station type

(rural or residential stations). Statistical survey (minimum, maximum and mean

standard deviation) by geographically near groups of background stations.

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If a station gives an hourly maximum noticeably higher than other stations in

the sector (e.g. factor 2), check against the previous day or beyond. If the

deviation is persistent and there is a doubt about the device‘s proper

operation, invalidation of the data (at least as long as it takes to do further

checking).

• Nearly systematic comparison of hourly values of O3 with NO and NO2 for the

stations that measure them. Checking of the NO/NO2 - O3 anti-correlation.

• Analysis of meteorological conditions, basically maximum temperature and

hours of sunshine. Refinement on the wind speed that might ‗dilute‘ a

photochemical phenomenon by high temperature.

• In residential areas, a survey of the drop of the O3 concentration at night for

high simultaneous quantities of NO.

• For rural stations, case by case survey by geographical area as a function of

the wind conditions (a risk of an urban plume effect downwind from an urban

area), possibly the taking into account of the entry into the region by an air

mass already polluted (O3precursers) upstream.

1.3.4.4. Nitrogen oxides (NO and NO2)

• Systematic rule for chemiluminescence measuring devices: hourly data

invalidated for NO is also for NO2 whatever the reason (the metrological

principle). NO can remain valid even if NO2is invalid because of a NOX path or

a converter oven problem.

• A check of the NO/NO2 - O3 anti-correlation.

• Surveys of meteorological conditions, the large influence of two meteorological

factors: wind speed and temperature inversions.

• Compared evolution of NO/NO2.

• Awareness of the values of vehicle counting loops if they exist.

Nitrogen monoxide (NO)

• Statistical survey (minimum, maximum and mean standard deviation) by

geographically close background stations.

• If a station gives an hourly maximum noticeably higher than other stations in

the sector (e.g. factor 2), check against the previous day or beyond. If the

deviation is persistent and there is doubt about the device‘s proper operation,

invalidation of the data (at least as long as it takes to do further checking).

• Survey of the dynamics, check on the simultaneous rise in levels.

• Criterion of return to the minimum threshold when the dispersion conditions

are satisfactory and the emissions are low (night-time levels).

• With NO being highly dynamic (a primary pollutant very sensitive to the

dispersion state of the atmosphere), maximum value comparisons are not

easy. For each station, judgement of the exceptional values as a function of

the usual maxima and historical values.

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• In traffic proximity situations, correlation with CO. Take the specificity of the

site into account (vehicle speed affecting the NOx emission rate), the daily flux

and the daily distribution of vehicles.

• The NO levels must remain higher in proximity than in background, even if the

deviations are noticeably reduced in case of pollution peaks.

Nitrogen dioxide (NO2)

• -The dynamics are much weaker than for NO, given the nature of NO2 (a

secondary pollutant) and its greater spatial homogeneity.

• -Statistical survey (minimum, maximum and mean standard deviation) by

geographically close background station groups.

• If a station gives an hourly maximum noticeably higher than other stations in

the sector (e.g. factor 2), check against the previous day or beyond. If the

deviation is persistent and there is doubt about the device‘s proper operation,

invalidation of the data (at least as long as it takes to do further checking).

• -Knowledge of the site and its usual behaviour, knowledge of particular local

phenomena, NOx/O3 consistency.

• -In large urban areas, the NO2 mean of proximity traffic is, in periods of good

dispersion, generally higher than the NO2 background mean. In polluted

periods, the levels of background NO2 draw nearer to those of proximity NO2,

the maximum hourly values even possibly exceeding those of proximity.

1.3.4.5. Particulates (PM10, PM2.5)

• Check for good spatial homogeneity in background situations.

• Check for fairly smooth profile, more than for the NO which presents stronger

dynamics.

• Check that the concentration of PM10 is higher than the concentration of PM2.5

on a same site measuring these two parameters.

1.3.4.6. Carbon monoxide (CO)

• Comparison with other CO analysers on sites with the same characteristics.

• Correlation with the NO and BTX of the same site (mainly in automobile

proximity).

• Awareness of the values of vehicle counting loops if they exist.

1.3.4.7. BTX (automatic device)

• Dynamics survey, check of the simultaneous rise in the levels of benzene and

toluene.

• Comparison between benzene, toluene and xylene (at near traffic station, the

ratio usually encountered is 1-3-1 between benzene, toluene and xylene, yet

given this ratio‘s considerable fluctuation, it is given here as an illustration

only).

• Correlation with the dynamics of CO and NO.

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1.3.4.8. Wind direction

• Survey of the dynamics (no excessive change of direction by established

wind).

• For the synoptic stations, check for the simultaneousness of directions by

comparison with other stations.

• Take the wind speed (no wind) into account. If wind speed is below 0.5 m/s

invalidate the wind direction.

1.3.4.9. Wind speed

• Survey of the dynamics, check for speed homogeneity by comparing with

other synoptic sites.

• Comparison of data with other sources (e.g. Meteo Service).

• For wind speeds automatically invalidated when they are less than a

predefined threshold (e.g. 0.5 m/s), it is necessary to revalidate all speeds

under this threshold so as to avoid greatly over-estimating the annual mean.

1.3.4.10. Temperature

• Survey of the dynamics, check for the simultaneousness of the rise in levels.

• Comparison of data with other sources (e.g. Meteo Service).

• Possible survey of temperature gradients.

1.3.4.11. Relative humidity

• Survey of the dynamics, check for the homogeneity of the relative humidities in

comparison to analogous sites (e.g. inter-urban, inter-rural).

• Check for the relative anti-correlation humidity and temperature (excluding the

probe‘s saturation areas).

• Comparison of data with other sources (e.g. Meteo Service).

• Check in a rainy period (over 30 minutes) that the relative humidity reaches

1.3.4.12. Sunshine

• On a clear day, check the ―bell‖ shape of the overall sunshine curves.

• Mind on shadow influence from buildings and trees

• Comparison of data with other sources (e.g. Meteo Service).

1.3.4.13. Pressure

• Fairly smooth profile.

• Comparison of data with other sources (e.g. Meteo Service).

• Take into account deviations / corrections due to the altitude.

1.3.5. Traceability of the validation

The traceability of data validation allows the network operators to have a full follow-

up of the different stages followed by data until validated data are obtained. The

following are the main points to implement:

Authorisation

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A list of the persons authorised to validate AQ data should be kept and updated.

Validation report

The validation operator should keep a record of all actions carried out in the

validation stages.

The validation report should contain at least:

• the name of the validation operator;

• the date and time of the validation;

• the station and the sensor in question;

• the nature and reason for the action on the data;

• the date and time of the start and finish of the action on the data;

• the proof in case of a problem that the problem has been taken into account

by the proper services.

The validation report can either be in hard-copy or computerised.

Computer applications

For the computer applications used for automatic prevalidations and assisted

validation, it is necessary to have the following information:

• identification of the application with a follow-up of the different versions (and

modifications);

• operating tests (initial and periodical).

1.4. Further handling of the validated data

After validation, validated data are stored in the networks database.

These validated data will be processed, even interpreted, afterwards. The validation

of processed data (processed and/or interpreted) should make it possible to ensure a

certain level of quality for this information distributed by the network.

1.4.1. Data processing

For validated data and for a given period, data processing consists in:

• establishing useful quantities for the interpretation or other processing, i.e.

mean, median, percentile, maximum value, minimum value, air quality index

and so on;

• associating the quantities obtained by successive sequences (temporal

evolutions of values), by class of values (distributions, threshold exceedances,

pollution roses, etc.) or by site (spatial aggregation, data mapping, etc.);

• processing statistics on data sets (regression, analysis, etc.);

• carrying out modelling.

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1.4.2. Data interpretation

In a well argued, detailed way, the interpretation consists in describing, explaining,

commenting on and/or forecasting the air quality from the data obtained after

processing:

• by taking the defined objective into account (e.g. information of the population,

emission reductions, impact studies);

• regarding air quality standards, impact references, levels measured at other

sites and other comparative or indicative data;

• as a function of the emission sources, geographical locations, meteorological

conditions or any other influencing factor;

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Annex 1: Examples for detection limits (depending on the operated measuring

devices and the test results of these analysers)

Component Detection Limit

[µg/m3]

½ - Detection Limit

[µg/m3]

SO2

AF21M 4.8 2.4

APSA370 2.4 1.2

TE43C 4 2

NO

AC31M 2.6 1.3

APNA370 1.4 0.7

TE 42 C 1 0.5

NO2

AC31M 3.8 1.9

APNA370 4.0 2.0

TE 42 C 1.2 0.6

O3

O341M 3.2 1.6

APOA370 2.6 1.3

CO

CO11M 230 115

TE48 230 115

APMA370 70 35

H2S (APSA350) 2.6 1.3

BTEX

CP7001 0.2 0.1

Synspec GC955 0.2 0.1

Particulate Matter PM10

Sharp 5030 5 2.5

TEOM1400ab 3 1.5

FH62IR 5 2.5

FH62IN 10 5

Particulate Matter PM2.5

Sharp 5030 5 2.5

TEOM1400ab 3 1.5

FH62IR 5 2.5

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Annex 2: Table of minimum validation criteria common to all pollutants

Technical and environmental surveys do not specifically refer to persons or

departments. They characterise the nature of the validation operations to be carried

out.

• The present state of the network taken into account:

- checking the data acquisition

- visualisation of the alarms of the measuring devices

• Examination of the assessment of the preceding maintenance operations:

- maintenance planning taken into account

- dysfunctions taken into account

- technical criteria specific to each measuring device taken into account

• Examination of the measuring device responses to the automatic calibration

checking operations:

- survey of fixed tolerance exceedances (invalidation, may be systematic,

of the data concerned by such an event)

- survey of fixed tolerance exceedances (e.g. search for cause - device

drift or calibration system dysfunction)

• Examination of programmed value exceedances:

- detection limits and maxi thresholds

- guide values, limits, warning thresholds

• Examination of the previous validation reports

• Survey of the data relevance:

- detection of outliers

- search for typical profiles, relevance of site type

• Survey of the spatial consistency of data:

comparison of evolution profiles between geographically close stations and

with the same site type

• Survey of the temporal consistency of the data:

- examination of typical profiles (e.g. day, week, weekend, season)

- event parameters taken into account

• Survey of the physical-chemical consistency of the data:

- verification of the correlation or the anti-correlation between pollutants

- assessment of the recorded concentration levels

• Suitability of the meteorological conditions (e.g. wind, temperature, sunshine,

temperature, inversions, rainfall)

• Use of knowledge and acquired experience (usual behaviour, local

phenomena with difficult judgements due to a specific event)

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II. Recommendations on the

Calculations of aggregated Data and statistical Parameters

1. Objective and purpose

The measured data are kept as hourly averages in the database of the monitoring centre. The processing and condensation of the data into statistical parameters is necessary to compare with the assessment criteria for emission measurement data, to assess emission and to fulfil the reporting obligations to the EU.

This instruction defines how to calculate corresponding parameters and statistical parameters like 8 hourly, daily, monthly and yearly average values and other parameters like limit exceeding values, percentiles etc. from the generated measured values of the air monitoring network. As a basis therefore, the legal guidelines in accordance with the EU Directive 2008/50/EC ―Air Quality and Clean Air for Europe‖ shall be consulted.

2. Scope

This instruction is valid for the calculation of parameters and statistical parameters of

data determined by automatic measuring devices of the air monitoring network in the

measurement centre.

Therefore it is not applied to particulate matter PM10 und PM2.5 if measured

gravimetrically and consequently also not for PAH and heavy metals in PM10 und

PM2.5.

3. Definitions and Abbreviations

Parameters and statistical parameters

Are processed from quantities calculated by the automatically

measuring devices according to the determinations pursuant to the EU

Directive 2008/50/EC Annex VII. The time basis is generally CET UTC

+2 without taking the summertime into account.

DL Detection limit: The smallest concentration of a measurand that can be

reliably detected by a specific measurement process, calculated e.g.

according to prEN 14212:2010 (E) as 3,3x(sz/B), where sz is the

standard deviation of instrument response at zero concentration and B

is the slope of calibration function (see examples in annex 1).

AOT40 (expressed in [μg/m3] * h) is the sum of the difference between the

concentration over 80 μg/m3 (= 40 ppb) as 1 hour mean and 80 μg/m3

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237

during one defined time period under sole usage of the 1 hour mean

between 8 h in the morning and 20 h in the evening (UTC +2) every day.

Average All parameters here defined as average are calculated as arithmetical

average.

n

i

ixN

x1

1

4. Definition of the procedures

4.1. Calculation of parameters

For all pollutants measured in the monitoring network with automatic registered

procedures, 1 hourly averages are the basis for all evaluation. These 1 hourly

averages were beforehand calculated by the station computers depending on 1

minutely averages. These result from actual measurements of each 5-second

measured value determined by the analysers. Here a minimum availability (=

minimum data capture) is in force. For the 1 minute average to be valid, the

percentage hereof is 75%. The availability of the data for the calculation of a valid 1

hour average must be 75%. This means that to determine a 1 hour average, 45 valid

1 minute averages per hour are necessary, otherwise the measurement value shall

be assessed as invalid.

The 1 hour averages are requested by the monitoring network centre in predefined

intervals and are saved in the database. So, 1 hour averages are saved in the

database for the components benzene, carbon monoxide, PM10, PM2.5, sulphur-

dioxide, nitrogen dioxide, nitrogen oxide, and ozone.

For the components carbon monoxide and ozone hourly gliding 8 hourly averages

are calculated basing on the 1 hourly averages. This can only be done if 75% of the 1

hourly averages are valid. This means that at least 6 of 8 1 hourly averages must be

available. The first 8 hourly average of a day is marked by the time 01.00 and covers

the averaging period from 17h of the day before until 1h of the next day. The last

eight hour average of a day begins at 16h.

Daily averages for PM10 and SO2 are calculated basing on 1 hourly averages. For

the calculation of a valid daily average at least 18 1 hourly averages of a day must be

available.

The yearly average of the pollution for benzene, PM10, PM2.5, sulphur dioxide,

sulphur oxide, and ozone are calculated basing on the 1 hourly averages of a year.

To fulfil the data quality targets of the EU Directive at least 90% of the 1 hourly

averages of a year (except: 75% for ozone) must be available. If the availability of the

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data is not within the named minimum requirements, the calculated yearly averages

shall be indicated with ―not conform with the data quality targets of the EU Directive‖.

The requirements concerning the availability of data do not cover the loss of data

because of regular function controls and calibration and the ordinary maintenance of

the measuring devices and the station.

Additional requirements concerning the calculation of parameters can be found in the

following Tables 1 and 2.

To calculate the parameters and statistical parameters in order to examine the

validity according to the EU Directive 2008/50/EC Annex VII the following criteria

shall be applied for ozone (Table 1):

Table 1: Criteria for the calculation of parameters for ozone

Parameter Necessary share of valid data

1hour mean 75% (means 45 minutes)

8 hours mean 75% of the value (means 6 hours)

Maximum daily 8 hours mean out of hourly gliding 8 hours mean

75% of the hourly gliding 8 hours mean (means 18 daily 8 hours mean)

AOT402 90% of the 1 hour mean during the calculation of the AOT40 value determined period3

Yearly average

75% of the 1 hour mean respectively separated during summer (April-September) and winter (January-March, October-December)

Number of exceedances and maximum values per month

90% of the maximum 8 hours mean of the days (27 available daily values per month) 90% of the 1 hour mean between 8:00 and 20:00 h UTC+2

Number of exceedances and maximum values per year

5 of 6 months during summer (April to September)

For the remaining pollutants the following criteria basing on the EU Directive

2008/50/EC Annex VII are valid (Table 2).

2In cases where all possible measured data are not available the following factor shall be used to

calculate AOT40 values:

with ―possible total hours‖ being the number of hours within the time period of AOT40 definition (i.e. 08:00 to 20:00 CET from 1 May to 31 July each year for vegetation protection and from 1 April to 30 September each year for forest protection)

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Table 2: Criteria for the calculation of parameters

Parameter Necessary share of valid data

1 hour mean 75 % (means 45 minutes)

8 hours mean 75 % of the values (means 6 hours)

Maximum daily 8 hours mean 75 % of the hourly gliding 8 hours mean (means 18 daily 8 hours mean)

24 hour average 75 % of the hourly averages (means minimum 18 daily 1 hour mean)

Yearly average 90 % of the 1 hour values or (or not available) the 24 hours value of the year

Furthermore the following calculation rules according to

- EU Council Decision2001/752/EC as well as

- Guidance on the Annexes to Decision 97/101/EC on the Exchange of

Information as revised by Decision 2001/752/EC

shall be taken into account.

98/99.9-Percentile, Median and Maximum Value

98/99.9-Percentile and maximum value shall only be calculated if minimum 75% of

the data is available. The median shall only be calculated if minimum 50% of the data

is available.

In this context the allocation of the data losses shall be given importance. This means

having 75% of data available, the loss shall not be crucial in winter or summer. The

ratio of the available data of the most occupied half-year to the number of available

data of the less occupied half-year shall not exceed 2.

4.2. Conversion factors

A conversion of volume ratios into the mass concentration is necessary. Therefore

the following factors shall be applied:

For gaseous pollutants the standard conditions are 20°C and 1013 hPa.

For SO2, O3, NO, and NO2:

1 μg/m3≙ F ppb 1 ppb ≙ 1/F μg/m3

For CO:

1 mg/m3≙ F ppm 1 ppm ≙ 1/F mg/m3

Table 2: Molecular Mass and Conversion Factors

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Molecular mass

g/mol Conversion Factor [F]

SO2 64.1 2.6647

NO 30.0 1.2471

NO2 46.0 1.9123

CO 28.0 1.1640

O3 48.0 1.9954

C6H6 78.1 3.2468

F = Conversion factor of mg/m3 in ppm and/or ppb in μg/m3, given for the reference

temperature of 20°C (293,15 K) at corresponding 1013,25 hPa (for a molecular

volume = 24,055 l/mol).

1 ppb ≙ 1 nmol/mol = 10-9 mol/mol

1 ppm ≙ 1 μmol/mol = 10-6 mol/mol

4.3. Availability (Data Capture)

The availability given in percentage is defined as the relation of the number of the

real identified basic data, to the data possible in the reference period. The time spent

for the calibration, conditioning, function control and maintenance is subtracted from

the number of possible ambient air measurements in the reference period.

According to the data quality objective „minimum data capture― defined in the Annex I

of the EU Directive 2008/50/EC, an availability of minimum 90% per month,

measuring station and pollutants is foreseen (exception: ozone during winter with

75%).

Example calculation:

1 month with 30 days, 24 x 30 one hour mean values = 720 one hour mean

values

Number of possible one hour mean values for the ambient air measurement:

= 720 one hour mean values

Pump breakdown, failure: 27 one hour mean values

Availability (%) = 100×(720-27)/720 = 96%

4.4. Realisation

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The calculation criteria defined in 4.1 are mapped in the calculation instructions. If at

least 50% of the measurement data is available, the calculation of the yearly average

is done differently from the availability defined in 4.3. This is necessary, as

sometimes the requirement of the availability of data of 90% is not met by some of

the components (e.g. BTX). So an average can be calculated even if the data quality

targets are not reached. In order to examine whether the used data record meets the

required rule of availability of data, the availability percentage out of the valid

measurement data is determined.

If the availability criteria are not met, the calculated parameters are marked by

corresponding explanations when publishing or reporting.

4.5. Data correction

Parameter < Detection Limit

In some of the measurement network captured components, the calculated

parameters as the annual average values could be smaller than the detection limits

of the used measuring device basing on a general low pollution level (e.g. in case of

sulphur-dioxide) or depending on the location of the measuring station (strong traffic

influence or far from traffic). In such cases, the half of the detection limit of the

measuring device shall be given as a value instead of the calculated value, when

publishing the parameter in reports or in the internet. Furthermore the value shall be

marked with a corresponding remark.

The detection limit is depending on the component and the used measuring device

type. Table 3 summarizes the detection limits of measuring device used in the

monitoring network (examples).

Due to the diversity of measuring device types and the corresponding detection

limits, for technical procedures for some components uniform detection limits can be

used.

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Table 3: Device Specific Detection Limits

Component Detection Limit

[µg/m3]

½ - Detection Limit

[µg/m3]

SO2

AF21M 4.8 2.4

APSA370 2.4 1.2

TE43C 4 2

NO

AC31M 2.6 1.3

APNA370 1.4 0.7

TE 42 C 1 0.5

NO2

AC31M 3.8 1.9

APNA370 4.0 2.0

TE 42 C 1.2 0.6

O3

O341M 3.2 1.6

APOA370 2.6 1.3

CO

CO11M 230 115

TE48 230 115

APMA370 70 35

H2S

(APSA350) 2.6 1.3

BTEX

CP7001 0.2 0.1

Synspec GC955 0.2 0.1

Particulate Matter PM10

Sharp 5030 5 2.5

TEOM1400ab 3 1.5

FH62IR 5 2.5

FH62IN 10 5

Particulate Matter PM2.5

Sharp 5030 5 2.5

TEOM1400ab 3 1.5

FH62IR 5 2.5

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4.6. Rounding / Evaluation

4.6.1. Rounding

The rounding of the aggregated data is always the last step of an evaluation before

the examination of compliance and/or exceedance of the limit, target values. Multiple

rounding shall absolutely be avoided.

The so-called commercial rounding shall be used:

If the digit on the first decimal place after the rounding is 0, 1,2,3 or 4 then it is

rounded down.

If the digit on the first decimal place after the rounding is 5,6,7,8 or 9 then it is

rounded up.

Advice: While processing single values with more than one decimal place, no

difference between the commercial and ISO rounding shall be expected.

4.6.2. Examination of the limit value exceedance

The examination of exceedances is done with regard to

the limit value

target value

long term targets

information thresholds

alert thresholds

critical levels

following the three steps mentioned below:

Aggregation of the data on the average period of the limit, target value inter

alia with all decimal places of the single values (at least one decimal place

more than the limit, target value inter alia).

Rounding of the aggregation results to the same number of decimal places, as

the limit, target value inter alia has. The target value for benzo[a]pyrene shall

be interpreted as 1.0 ng/m³.

Examination of the exceedance of the limit, target value inter alia.

Examples:

Examination of the exceedance of the annual limit for NO2 of 40 µg/m³

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Calculation result: 40,3 μg/m³

=>Rounding: 40 μg/m³ => limit not exceeded

Calculation result: 40,6 μg/m³

=>Rounding: 41 μg/m³ => limit is exceeded

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III. Annexes – Examples for

procedure instructions for data centres in

Austrian and German Air Quality Monitoring Networks

III.A1: Automatic Validation

of Air Quality Data

1. Purpose

This procedure instruction describes the procedure, the parameterisation and control

of the process of automatic validation of measurement data for the monitoring of air

quality. The automatic validation in the monitoring network centre especially serves

the pre-verification of measurement data for real time publications with selected

methods. Additionally, with the help of automatic validation, out of the ordinary

pollution situations can be recognized, if the parameterisation is appropriate.

2. Scope

The regulations are valid for the automatic pre-verification of online acquired

measurement data.

3. Terms/Abbreviations

Automatic Network Centre Validation: Measurement data control by means of a

software

Validation rule: Algorithm for the automatic verification of

measurement data

4. Procedure Description

4.1. Basic description

The data control of measurement data in the monitoring network takes place in

several steps. The first step is the automatic pre-verification, which comprises the

automatic validation in the station and the automatic validation in the monitoring

network centre. At the automatic pre-verification in the station data controls are

performed by a data acquisition software by means of the 1-minute average values

(e.g. minimum values, maximum values, data capture rates). During the automatic

validation in the network centre, several pre-verifications of the 1-hour average

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values are performed by means of a software system (minimum values, maximum

values, concentration rises, constant values etc.).

The following (manual) data control comprises the steps:

Daily data control

Monthly data control

Data control after calibration and

Control before the yearly report

A more detailed description is to be found in the section III.A2 ―Control and Release

of Air Quality Data‖.

The automatic network centre validation is the verification by means of a software of

air quality and meteorological measurement data, or of other data acquired in the

network by means of a software tool. This software uses up to eight different

validation rules with parameterisations, which can be set freely. The validation rules

and parameterisations used are documented in this paper.

The following validation rules are available:

ConstantValue: Verification of equal values

NegativeValuesInvalid: negative values below the negative detection limit are

set invalid.

VerificationMRL: Verification of the measurement range

VerificationThresholdValue: Threshold value, at which the step height test is

initiated.

StepHeightRegress: Step height test

StatusAdjustment: Status adjustment for corresponding components.

Pre-treatment

ValueRise

The rules are described in the manual to the software „automatic monitoring network

centre validation―, which is part of this PI.

For each station-component combination is must be established which rules are to be

used and how the rules are adapted to the concrete station-component combination.

This takes place by means of parameterisations.

In many cases it is sufficient if the parameterisation of validation rules is related to the

component, i.e. is independent of the station. In the case of specific pollution

characteristics on individual measurement stations, for instance in the case of

industry-related monitoring, parameterisations are used which have been adapted to

the typical pollution developments.

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4.2. Parameterisation of the automatic network centre validation

For each station and each air-pollutant component the rule allocation and the para-

meterisation can be performed by means of the software tool that is available. For

more help, refer to the manual of the software ―automatic monitoring network centre

validation‖

4.3. Control of the automatic network centre validation

The software for the automatic validation in the network centre records when an

automatic validation has been performed. The corresponding file is to be verified

daily by the employee of the network centre. Should there be any error message, the

chief of the monitoring network centre is to be notified. The notification shall take

place by means of emails.

A further protocol function of the software automatic network centre validation refers

to the status modification of measured values, which the programme has performed.

Measured values, which are recognized by the validation rules as ―invalid‖ receive

the status ―invalid‖ and are then recorded in the end database with this status. This

means that these measured values appear as invalid at all subsequent data

processing, which uses the data from the database. Therefore a very detailed control

and correction of the results of the automatic validation network centre is necessary.

For the enumeration of the validation protocols an appropriate module is available.

In the validation protocol the station, the component, the rule and the time of the

measured values, which have been marked invalid, are listed. The validation

protocols are to be verified daily by the employee of the network centre. All

modifications of the automatic validation network centre (label ―invalid‖) are to be

verified by means of comparison with the raw and final data. By means of an

appropriate module it is possible to visualise the evolution of the raw and final data

and to compare them directly in order to decide upon the plausibility of the status

modification.

Additionally, the plausibility of the modifications of the automatic pre-verification in the

centre is to be estimated. For the evaluation of plausibility, reference is also made to

the section III.A2 ―Control and Release of Air Quality Data‖, which describes the

procedure for manual data control.

The quality of the automatic pre-verification in the centre is to be evaluated

periodically. If need be, modifications of the parameterisation must be performed by

the chief of the monitoring network centre. The following principles must be observed

in the process:

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- Episodes with a short term rise of pollution concentrations may not be deleted

automatically (parameterisation of the upper and lower measurement range limits,

of the step height test)

- The automatic validation at the network centre should possibly only detect real

device errors and mark only those values as invalid.

5. Responsibilities

The person responsible for the parameterisation of the automatic validation is the

chief of the network centre.

Any changes in the parameterisation of the automatic validation may only be

performed by the chief of the network centre. He will fully document the changes

performed.

The employee of the network centre is the one responsible for the daily control of the

automatic validation. He will also check if the automatic network centre validation has

been performed and check the status modifications (invalid), which have been made

by the automatic validation. He decides - if need be, together with the chief of the

network service and/or the chief of the network centre - if the labelling of the

measured values as invalid was justified or not. The employee of the network centre

shall make the necessary changes of the status signals valid/invalid after assessing

the evolution of the measured values.

After the end of the month, a data control shall take place by the 20th of the following

month (cf. section III.A2 ―Control and Release of Air Quality Data‖). During this

monthly plausibility check, the status modifications of the automatic validation are to

be taken into consideration and to be controlled.

6. Further Applicable Documents

Section III.A2 ―Control and Release of Air Quality Data‖

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III.A2: Control and release of

Air Quality Data

1. Purpose

This procedure instruction regulates the course of action for data control and release,

as well as for any modifications of measured data that may be necessary.

2. Scope

The provisions apply to online-acquired measured data and to the results of the

gravimetric determination of the concentration of the PM fraction in the monitoring

network centre of the air quality monitoring network.

3. Concepts / Abbreviations

AV1 One-hour average values

Control

level Description

Frequency of online-

acquired results

Frequency of gravimetric

determination of PM

concentration

0 not sifted

1 sifted daily ("Daily data control") after every series of

measurements

2 verified monthly ("Monthly data control")

monthly

3 fully verified after station calibration ("Data control after calibration")

after station calibration ("Data control after calibration")

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4. Description

4.1. Data control – Online acquisition

4.1.1. Daily data control – manual plausibility check

Carried out by the responsible staff member of the monitoring network centre

Schedule daily (working days) 7:00 - 9:00

Information used AV1 automatic daily4 zero/span function control status bits information from the head of the Monitoring network service

Communication in

case of problems

Head of the Monitoring network service (or the staff member responsible for supervising the monitoring site) For specific problems: IT assistant; electricity supplier; telecom operator

Results are used for daily reports requests from third parties

During the daily data control and the plausibility check

the zero and span values of the daily automatic function control and the

ascertained AV1 are sifted and checked for plausibility;

the measured data highlighted by automatic validation are verified manually;

erroneous or evidently implausible AV1 are invalidated;

the control level is set to 1 in the course of the daily data control;

the head of the Monitoring network service is informed about the technical

problems that occurred at the monitoring sites.

The verification is carried out by the staff member of the monitoring network centre

that is responsible for this task, every working day (Mo-Fr) until 9 o‘clock. After non-

working days, the period since the last data control is to be taken into consideration.

Criteria for the first manual plausibility check – the invalidation of implausible values The results of the automatic plausibility check are sifted. Automatically invalidated

values are validated, if they are considered plausible. In addition the values

considered implausible are invalidated manually. In this process, the experience that

the staff member of the monitoring network centre performing the check has in regard

to concentration levels to be expected at each monitoring site plays an essential role.

4every 23 or 25 hours

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The plausibility check is carried out on the basis of:

AV1

the person performing the check can also draw upon minute average values

as decision guidance

zero and span values

information from the Monitoring network service regarding problems at the

monitoring site

status bits (identification of technical problems)

information from the automatic plausibility check

the internal space temperature and the humidity inside the monitoring

container

airflow velocity in the intake pipe

If the zero and span values of the daily automatic function control exceed the

established criteria, the heads of the Monitoring network service is to be informed.

Indices for the identification of implausible values:

identification of technical problems on the basis of the status bits;

measured values that clearly diverge from the ―usual‖ pollution course and that

are in all likelihood influenced by air other than ambient air (zero or span gas,

internal space air;

experience regarding the regular pollution patterns at the monitoring site (level

of concentration, daily course, dependency on wind direction, sources that

influence the monitoring site…);

airflow velocity in the intake pipe falls below a critical value (defective

ventilator/pump);

the temperature and humidity values in the monitoring container lie outside the

value range required for the operation of the measurement instruments;

moreover, in the case of conspicuously high values one must also investigate

whether these could have been caused by exceptionally high emissions in the

vicinity of the monitoring site. The comparison with other monitoring stations

nearby can help to identify potential long distance transports.

Procedure and information in case of technical problems In case of data transfer failure from individual stations the first thing to be done is the

manual initiation of data transfer in the network centre. If the connection cannot be

re-established the person in charge must clarify whether this could be the

consequence of failure in the telephone network.

The provided information about the daily data control documents problems related to

data transfer

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the individual measurement instruments (e.g. temporary failure, implausible

values, zero and span values of the daily automatic function control exceed

the established criteria)

the climatisation of the monitoring container and the ventilator/pump of the

centre intake pipe

The e-mail (Subject ―Daily data control, current date‖) should inform about the

existing problems as precisely as possible – on the basis of the messages in the

monitoring network and the status bits in the data control.

The following persons are to be informed:

Failure of the entire monitoring network IT-Assistant5

Failure of one station Head of Monitoring network service,

telecom operator; electricity supplier;

Problems with the individual measurement

instruments

Head of Monitoring network services

Zero and span values of the daily

automatic function control exceed the

established criteria

Head of Monitoring network services

Problems regarding the climatisation of the

station and the ventilator/pump of the

centre intake pipe

Head of Monitoring network services

The head of the Monitoring network service is responsible for taking the necessary

measures.

5the persons responsible for the EDP-technical support for the operation of the monitoring network centre,

incl. modems

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4.1.2. Monthly data control

Carried out by The responsible staff member of the monitoring network centre

Schedule Until the 20th of the following month

Information used

AV1 Zero and span values of the daily automatic function control Zero and span values of the biweekly station check Information from the Monitoring network service (especially from the biweekly station check) Status bits Recorder strip charts

Communication in case of

problems Head of the Monitoring network services

Corrections in consultation with Head of the Monitoring network services

Results are used for Monthly report Requests from third parties

The monthly data control and plausibility check for the preceding month is carried out

by the staff member of the monitoring network centre responsible for this and

comprises:

a general check of the measured data of the preceding month on the basis of

the results of the biweekly zero/span check (monitoring site check), the zero

and span values of the daily automatic function control and the recorder strip

charts, as well as the entries in the station logbook;

a check of the amount of valid data (documentation of the cause(s) of longer

malfunction periods);

depending on the case, setting negative values below negative detection limit

invalid.

This data control is carried out monthly until the 20th of the following month at the

latest, in any case before the preparation of the monthly report.

It is performed as soon as the recorder strip charts and the zero and span values of

the first station check are available. Data corrections may be performed only after

consultation with the head of the Monitoring network service.

As part of the monthly data control the control level is set to 2.

The forms with the zero and span values of the biweekly station check (or copies

thereof) shall be picked up from the monitoring network centre on the occasion of the

first check of the month.

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The recorder strip charts are also to be picked up from the monitoring network centre

on the occasion of the first check of the month, as well as a carbon copy of the

station logbook.

Criteria for the monthly data control – invalidation of implausible values The monthly data control comprises the invalidation of the values for which it was not

possible to make a plausibility assessment during the daily data control.

If necessary, AV1 that were invalidated in the course of the daily data control are

validated, if the information available at this point indicates that they are actually

correct.

The assessment of the values shall be made on the basis of the information from the

daily data control and also on the basis of information from the Monitoring network

service regarding the biweekly station check and the recorder strip charts.

Assessment criteria:

in case of potential device malfunction one must judge, on the basis of

observations from the biweekly station check (zero and span values, technical

problems regarding piping, filters, cabling, pumps or valves, problems with

switch-on after a power blackout), whether some values must be invalidated;

measured values that are considered to have been influenced by device

problems or by switch-on problems are invalidated;

measured values that clearly diverge from the ―usual‖ pollution course and that

are in all likelihood influenced by air other than ambient air (zero or span gas,

internal space air);

in the case of value drifts and trends regarding zero and span values further

verifications are necessary (values are not invalidated);

if the zero or span values of the daily function control exceed the established

criteria one must appraise whether these values should be corrected or

invalidated;

in the case of unusual high values one must also investigate whether these

could have been caused by exceptionally high emissions in the vicinity of the

monitoring site or by long distance transports.

AV1 that are assessed to be evidently implausible are invalidated.

Treatment of negative values In case negative values are registered over a longer period of time whereas the

instrument zero is marginally negative (daily or biweekly function control) one shall

investigate whether there are reasons for a systematic deviation that is to be

corrected. Random deviation arround zero can be accepted if the values are above

the negative detection limit. Negative AV1 to be published in the monthly report is set

to ´ detection limit (never publish negative values!)

The following criteria are to be taken into consideration:

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zero and span values of the biweekly station check;

zero and span values of the daily automatic function control;

assessment of problems with the analog output of the biweekly station

check;

changes in the measurement instrument made in the course of calibration;

value pattern.

4.1.3. Data control after calibration

Carried out by the responsible staff member of the monitoring

network centre

Schedule after the quarterly station calibration, in any case

before the preparation of the annual report and the

data transmission to the national data centre

Information used quarterly station calibration

AV1

Zero and span values of the daily automatic function control Zero and span values of the biweekly station check Information from the Monitoring network service (from the biweekly station check and the station calibration) Status bits Recorder strip charts

Communication in case of

problems

Head of the Monitoring network service

The Monitoring network service staff member who performed the calibration Head of the calibration lab

Corrections in consultation with Head of the Monitoring network service The Monitoring network service staff member who performed the calibration

Results are used for annual report data transmission to the national centre requests from third parties

The data control is carried out after the results of the quarterly station calibration are

available, in any case before the publication of the annual report and the

transmission of the data to the national data centre.

The control comprises

possible corrections, according to the results of the station calibration,

after consultation with the head of the monitoring network service and the

monitoring network service staff member who performed the calibration;

a second plausibility check for the entire period of time passed after the

last calibration.

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The assessment is based upon the same criteria as in the case of the monthly data

control, plus calibration results.

The control level is set to 3.

Corrections Corrections are carried out using a transfer standard, on the basis of the results of

the station calibration.

The calibration results are assessed by the staff member who performed the

calibration together with the head of the Monitoring network service and, if necessary,

the head of the calibration lab is also consulted. On the basis of this assessment the

decision is taken whether corrections are necessary for the time period concerned.

Criteria for performing a correction of a zero or span deviation and for delimiting the

period of time over which the correction must be carried out:

zero and span values ascertained during station calibration

zero and span values of the biweekly station check

zero and span values of the daily automatic function control

maintenance of the measurement instrument carried out since the last station

calibration

information from the monitoring network service with regard to problems that

occurred after the last station calibration.

Corrections are made on the basis of the function y=kx+d.

Ccorr (t) = Corig (t) * k (t) + d (t)

C concentration

t time

k factor for the correction of the span deviation

d offset correction of the zero deviation

corr corrected

orig original

k and d shall be ascertained from the calibration results.

4.2. Data control – Gravimetric determination of the concentration of the PM

fraction

4.2.1. First plausibility check

The determined measurement values (weighing results from one series) are checked

for plausibility by the employee of the calibration lab responsible for this.

Criteria for the plausibility check:

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experience regarding the filter masses to be expected at the monitoring;

comparison with the neighbouring monitoring sites

optical analysis of the relationship between the filter mass and their degree of

blackening.

Negative values of the determined dust mass are in any case to be questioned.

4.2.2. Monthly data control

The monthly data control is carried out by the monitoring network centre and

comprises:

a check of the integrity and plausibility of data

a check of the quantity of valid data (valid: at least 75% of the suction time of

- normally - 24 hours)

a comparison between gravimetric and continuous measurements: parallel

variation in time, correlation/regression

a comparison between the different PM fractions (e.g. proportion PM2.5/PM10)

a comparison with the PM concentrations from other monitoring sites

the documentation of problems at the monitoring site (sampling device).

In the course of the monthly data control the results of gravimetric measurements are

compared with the corresponding data from continuous measurements of PM

concentrations (daily average values). The comparison is made in terms of the

variation in time and the correlation of the PM10 concentrations. Moreover, if more

PM fractions are measured, the ratio of the individual concentration is verified.

Corrections are carried out after consultation between the monitoring network centre,

the responsible employee of the Monitoring network service (documentation of

problems at the monitoring site), the responsible employee of the calibration lab and

the head of the calibration lab.

This data control takes place monthly, until the 20th of the following month.

4.2.3. Data control after calibration

The data control is performed following the flow calibration of the sampling device. In

case of deviation of the volume flow the head of the calibration lab must be informed.

He will decide what action needs to be taken next.

The following steps regarding control and release are analogous to the procedures

described in the section about online data acquisition.

5. Data control before the annual report

Before the annual report is published, the data from the whole year are once again

controlled. This control is carried out, on the one hand, on the basis of technical

criteria, in particular the results of the annual national and - if applicable -

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international balance, and on the other hand, taking into consideration meteorological

aspects and other aspects. The technical control is carried out by the head of the

Monitoring network service and the head of the calibration lab, whereas the rest of

the matters are controlled by the head of the monitoring network centre.

6. Documentation and storage

6.1. Daily data control

Prints of the daily zero-span checks (function control), the form for the documentation

of the daily data control and the e-mail containing information for the responsible

persons about current problems shall be placed in the corresponding files.

The form for the documentation of the daily data control must comprise at least:

the date

the employee carrying out the control

technical problems in the monitoring network

zero and span values of the daily automatic function control in the case of

which an intervention is necessary

the persons informed.

6.2. Monthly data control

All control steps shall be documented in the corresponding Excel files. All necessary

information is to be recorded in the table sheets of each monitoring site. The records

of the monthly data control as well as all further information necessary (e.g.

comparison of PM concentrations) are stored in station folders.

6.3. Control after calibration

The staff member who carried out the calibration shall record the information

regarding the calibration (station, date, components).

All control steps shall be documented in the corresponding files (stored/archived in

the folder for the appropriate calendar year).

In the course of the annual control at least the following information must be

documented (in part directly in the database):

station and components

time of calibration (and of correction)

reasons for corrections (for every correction step)

beginning and end date for the corrected values

k for beginning and end of the time period to be corrected (k=1, if no

correction was performed)

d for beginning and end of the time period to be corrected (d=0, if no

correction was performed)

when the correction was performed

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who performed the correction.

7. Data provision

7.1. Publication of data

Control level Use of data

Not sifted Up-to-date information of the public (apart from reports on air quality informing about

exceedances of the limit values or exceedances of the

information or alert thresholds)

Sifted Up-to-date reports on air quality (in case of exceedances of limit values or of

information or alert thresholds)

Verified Monthly report

Fully verified Annual report, national network centre (international reporting)

7.2. Data provision on request

Information regarding measurement results can be provided over the telephone,

specifying the appropriate control level.

The authorisation/permission for the written/electronic provision of data rests with the

head of the monitoring network centre.

Only data that have undergone final verification should be provided for scientific

application.

8. Further applicable documents

Section III.A1 ―Automatic Validation of Air Quality Data‖

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III.A3: Information of the

Public on Air Quality Data

1. Purpose

This procedure instruction describes the procedures used for informing the public

about air quality. It provides a closer description of the procedures sketched in the

chapters

- 3.1 Preparation of reports, statements, and data publication

- 3.2.4 Data publication

of the section III.A4 ―Reports, Statements, Publications‖.

2. Scope

These provisions apply to the publication of monitoring data on air quality provided by

the monitoring network as well as to the additional related information, which is

assessed and explicated.

3. Responsibilities / Definitions

The staff members who carry out activities within the scope of this procedure

instruction are also responsible, empowered and authorized to carry out the activities

described in these procedure instructions and in the related procedures.

4. Description of basic procedures

The implementation of the CAFE Directive and the current national legislation in the

field of air pollution control involves the continuous monitoring of air quality.

Obligations regarding the information of the public on air quality follow from this

monitoring obligation. These obligations are described in detail in the relevant EU

directives (cf. chapter 7. References).

These directives regulate the increased public access to environmental information.

The dissemination of this information contributes to a greater awareness of

environmental matters, facilitates the free exchange of opinions and a more active

public participation in environmental decision-making and is ultimately conducive to

improving environmental protection.

- The recipients of this information are the public, public authorities and relevant

organisations such as environmental organisations, consumer organisations,

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organisations representing the interests of sensitive populations and other

relevant healthcare bodies.

- Quality of information:

The information provided must be accurate, comprehensible and accessible

and must be disseminated actively and systematically.

- Content of information:

The information should include the air quality data and their assessment, as

well as further information concerning the measurement procedures

employed, the monitoring stations and the monitoring concept, plans and

programmes regarding the measures to be taken in order to improve air

quality, conduct recommendations to the population in the case of high

concentration of air pollutants and the causes of the pollution.

- Timeliness of information:

Depending on the respective air pollutant and the relevant limit and threshold

values the information regarding concentration shall be updated on an hourly,

daily, monthly or yearly basis.

In case an exceedance of the information or the alert threshold is ascertained

or forecast, the public must be informed immediately. This information should

also include a short assessment regarding effects on health.

- Dissemination of information:

Information concerning the air quality should be routinely made available by

means of radio, press, information screens/billboards, Internet, telephone,

fax/email, teletext or any other appropriate means, such as reports.

5. Information regarding measured air quality data

5.1. Data flow in the monitoring network centre

The data flow diagram in Picture 1 below provides an overview of the processes ta-

king place in the monitoring network centre with regard to the provision of different

types of information to the public.

The information is basically divided into two categories:

- information to be made available within a short period of time – this involves

the routine updating of information and the immediate provision of information

in case of ascertained or forecast exceedance of the information or the alert

threshold and

- information to be supplied periodically or when required.

5.2. Content and timelines of information

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The table below contains, for each air pollutant, the relevant parameters to be made

public and the required update cycles.

No. Information Pollutant Update

1 daily average value PM10 daily

2 hourly average value SO2, NO2 daily, if possible hourly

3 exceedance of limit/ alert

threshold SO2, NO2 in case of exceedance

4 annual average value lead every 3 months

5 annual average value benzene every 3 months, if possible

monthly

6 highest average 8-hour floating

value CO daily, if possible hourly

7 hourly average value ozone daily, if possible hourly

8 average 8-hour floating value ozone daily

9 exceedance of information/ alert

threshold ozone hourly

10 annual average value Cd, Ni, As, Hg,

PAH annually

Table 1:Overview of the content and timelines of measured data publication for

individual air pollutants

The calculation of all parameters, such as hourly, daily, monthly and annual average

values as well as further statistical parameters to be made available to the public,

including the comprehensive boundary conditions to be observed, is regulated by

section II. ―Recommendations on the Calculations of Aggregated Data and Statistical

Parameters‖.

These calculations are the basis for any publication of data. They are passed on

automatically in the case of hourly data; otherwise – if the averaging period for the

data is of at least one day – the data have at least passed through the first validation

stage.

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5.3. Measured data and information to be made available within a short

period of time

Requirements:

Particularly the timely publication of measured data on air quality requires functional,

automated process flows in the monitoring network centre to ensure that data

transfer from the station, automatic validation, calculation of necessary parameters,

threshold check, internal notification and automated forwarding/transmission of

measured data run smoothly. The head of the monitoring network centre must ensure

the permanent functioning of the appropriate programmes and instruments.

5.3.1. Hourly data

Data are routinely made available daily, automatically, on an hourly basis, between

the hours 6.00 and 21.00. The media used to disseminate the information are:

- internet

- teletext

- telephone announcement service

- information screens/billboards

- fax/ email

In parallel the set of measured data is automatically sent to the national data centre.

Before publication, the hourly updated air quality data undergo automatic pre-

validation only. Manual validation does not take place at this point.

As a matter of principle, the subject of data publication should be measurement

results that are appropriately checked, i.e. manually validated. This ensures that

incorrect data do not reach the public. If the data have not been manually validated

up to the moment of publication, this must be indicated in an adequate manner. This

concerns particularly the routine hourly and daily publication of data.

The publication of these data therefore includes the following notice to the recipient: “The measured data have been checked automatically but they have not gone through the whole validation process. They are subject to change. Further information is available on request.” In parallel to the hourly updated public information, the automatically pre-validated, complete and up-to-date data set on air quality is automatically transmitted to the national data centre, which ensures an up-to-date national overview on air quality throughout Serbia by means of the Internet.

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5.3.2. Daily report

The daily report is also made public within a short period of time, following manual validation, every working day at 9 o‘clock. This is the task of the staff member at the monitoring network centre. 5.3.3. Exceedance of limit values and of information/alert thresholds

In these cases the public is informed immediately regarding the individual averaging periods of the aforementioned parameters. The head of the monitoring network centre is responsible for this.

In the cases when alert thresholds are exceeded, the measured data are

manually validated before the information is made available to the public. This

is the task of the staff of the monitoring network centre. Outside of office hours

an on-call service ensures the manual validation and the dissemination of

information. When an exceedance of the alert threshold occurs, the staff of the

on-call service is informed automatically per SMS and the service is

immediately active.

In case of exceedance of limit values (SO2, NO2) or information thresholds

(ozone) the measured data are manually validated before the information is

made available to the public if the exceedance occurs during office hours.

Outside of office hours public information is carried out automatically, without

manual validation.

This information includes a short assessment of the scale of the exceedance of the

limit value and/or the alert threshold as well as a briefing regarding effects on health.

The minimum requirements for information, as they are stated in the EU directives,

are presented in chapter 5.3.4. using the example of the air pollutant ozone.

5.3.4. Timely public information regarding the air pollutant ozone

The procedure for the timely provision of information regarding the air pollutant ozone

– for which the EU established the most far-reaching obligations concerning public

information – is described in the following as an example.

Please note: The procedures for provision of information in the case of the other air

pollutants are in principle analogous. However, depending on the specific provisions

regarding the individual air pollutants, e.g. provisions referring to averaging periods or

type of limit value (alert threshold, limit value etc.), there are differences in procedure.

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Hourly information

- Requirement: hourly updated, automatically validated measured data (one-

hour averages) are available in the database.

- Publication of measured data is carried out automatically, on an hourly

basis, between the hours 6:00 and 20:00 without prior triage (manual

validation).

- Transmission of measured data to

o Internet (website)

o teletext regional TV stations

o information screens/billboards

o telephone announcement service

o national data centre.

- Presentation of the following items for all ozone monitoring stations:

o Internet

tables containing measured values – one-hour average

values (available for download)

tables containing measured values – floating eight-hour

average values

line graph on the basis of one-hour average values

area maps on the basis of one-hour average values.

o teletext

current one-hour average values

o information screens/billboards

current one-hour average values

o telephone announcement service

current one-hour average values.

- The staff of the monitoring network centre checks the correct presentation

in the media of the information provided – the accuracy of measured data

and the time of day when it is made available to the public.

- In case of error the staff of the monitoring network centre submits a

notification to the head of the centre and initiates error correction.

Daily report

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- Requirement: the automatically validated one-hour average values for the

past day, with a minimum data capture of 75%, are in the database.

- Immediately after day‘s end the calculation of the parameters for the daily

report is carried out automatically, without previous triage (manual

validation) of the one-hour average values used.

o highest one-hour average value of the day

o hourly average 8-hour floating value of the day

o highest average 8-hour floating value of the day

- The daily report is published on the Internet only. The publication is carried

out automatically in connection with the first publication of hourly measured

data the following day (at 6 am), without previous triage (and at 9 am

respectively, after the first manual validation).

- After the first manual data check on the following day (which can lead to

changes in the data set of the previous day), the staff member at the

monitoring network centre checks whether the parameters in the daily

report were calculated correctly - on the basis of the (now manually

validated) measured data of the previous day and whether the presentation

of the information on the Internet is being carried out properly.

- If the staff member at the monitoring network centre finds any errors, they

submit a notification to the head of the central and initiate error correction.

This may require the manual restart of parameter calculation for the daily

report as well as the subsequent updating of the information provided on

the Internet.

- Subsequently, the staff member at the monitoring network centre checks

whether the information provided is presented correctly on the Internet.

- If the staff member at the monitoring network centre finds any errors, they

submit a notification to the head of the central and initiate error correction.

Information provision to the press and to public authorities (every working day)

- Requirement: updated, automatically validated one-hour average values

for 3 pm are available in the database.

- The information contains the 3 pm ozone values from all monitoring

stations as well as a forecast of the highest one-hour average values

expected for the following day, generated by means of an automated

ozone forecasting model.

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- Before sending out the information, the staff member at the monitoring

network centre carries out a plausibility check for

o the 3 pm measured data to be made available

o the content of the forecast

and only then gives the green light for publication.

- The information is provided at 3:30 pm per email (or by fax, where

applicable as fax on demand) and also made available on the Internet.

- The content of the information is documented and the transmission

recorded, both by automated means.

- Recipients of the information are the press, the broadcasting media and

public authorities as well as further healthcare bodies, universities,

interested citizens, depending on the case. The distribution list is

documented.

- The information provided also includes contact possibilities for requesting

further information, such as website, telephone number and email address.

Exceedance of information/alert thresholds

If an exceedance of the ozone information threshold (180 µg/m³) or of the alert

threshold (240 µg/m³) is ascertained or forecast, the public must be informed

without delay.

- Requirement: hourly updated, automatically validated measured data (one-

hour averages) are available in the database.

- In case of exceedance of the aforementioned thresholds the information for

the public is generated automatically and prepared for transmission.

- The content of the announcement includes

o the current ozone measured data (one-hour averages) from all

stations of the monitoring network; monitoring stations affected by

the exceedance are flagged

o additional information in accordance with the minimum requirements

specified in /1/ CAFÉ Directive Annex XVI, such as

information on the population affected or on population

groups at risk, possible health effects and recommended

conduct

forecast for the following afternoon/day(s)

information on preventive action to reduce pollution and/or

exposure to it.

- At the same time the information is generated, an internal notification is

displayed on the screen of the staff member at the monitoring network

centre, indicating that

o an exceedance of the threshold for ozone has been ascertained in

at least one station and

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o after 15 minutes have passed the generated information regarding

the exceedance will be automatically sent out to the public.

- Within this timeframe, a manual validation of the measured data to be

made public can be performed. During office hours the staff member at the

monitoring network centre carries out the manual validation.

- The heads of the monitoring network centre and of the monitoring network

are then informed about the forthcoming automated transmission of the

information by the staff member at the monitoring network centre.

- In case the information has been generated erroneously because of

incorrect measured data, the employee at the monitoring network centre

terminates the process.

- Outside of office hours public information is carried out automatically,

without previous manual validation. If, in case of extraordinary exception,

incorrect information has been made public, the head of the monitoring

network must send the recipients of the erroneous information, at the

earliest possible time, a rectification including an explanation of the causes

for the occurrence.

- In principle, the information is made public only between the hours 11 am

and 8 pm.

- The information is provided per fax and/or email; it is also made available

on the Internet

- The content of the information is documented and the transmission

recorded, both automatically.

- Recipients of the information are the press, the broadcasting media and

public authorities as well as further healthcare bodies, universities,

interested citizens, depending on the case. The distribution list is

documented and can be extended by comparison with the distribution list

for daily information provision to the press and public authorities.

- The information provided also includes contact possibilities for requesting

further information, such as website, telephone number and email address.

5.4. Information to be provided periodically or when required

The periodical information of the public regarding measured data on air quality and

the provision of information on request are carried out by means of the Internet or in

print. It is made available to the public in the form of

- monthly reports

- annual reports

- special reports such as, for example

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evaluation of air quality data in accordance with applicable regulations

(EU directives)

contributions to air quality maintenance plans and action plans

evaluation of special pollution situations in the framework of special

monitoring projects

on the basis of data that have undergone verification (monthly reports) and final

verification respectively (annual reports, special reports).

5.4.1. Monthly report

The monthly report is prepared on the basis of the verified monthly data set on air

quality.

The necessary evaluations and parameter calculations are carried out according to

the specific requirements for individual air pollutants in the EU directives /1/. The

additional criteria for the calculation of parameters and statistical parameters

specified in the decision /4/ 2001/752/EC must also be observed.

5.4.2. Annual report

The annual report is prepared on the basis of the complete annual data set on air quality, after the data set has undergone final verification. The necessary evaluations and parameter calculations are carried out according to the specific requirements for individual air pollutants in the EU directives /1/, /2/. The additional criteria for the calculation of parameters and statistical parameters specified in the decision /4/ 2001/752/EC must also be observed. Furthermore, after undergoing final verification, the complete annual data set on air quality is transmitted to the national data centre until 31 March of the following year. Here the annual data sets from all regions in Serbia form the basis for EU reporting, which must be carried out annually until 30 September.

5.4.3. Special reports

Special reports are prepared on the basis of data that have undergone final

verification.

6. Other information for the public

This type of information refers to all additional information, explanations and

instructions that must be made available to the public in relation to the published

measured data, in order to enable the public to understand, assess and interpret the

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published air quality data as well as the measures taken by the competent

administration for improving air quality.

The head of the monitoring network is responsible for developing a concept for the

provision of this type of information to the public.

This information is prepared and completed gradually. In charge of this process are

the heads of the monitoring station, of the calibration laboratory and of the monitoring

network centre.

This type of information is in principle made available on the Internet. For increased

dissemination the basic/more important information is also made available in print, in

the form of brochures or leaflets that are provided free of charge. The purpose is to

reach wider population circles.

6.1. Air quality monitoring concept

The concept for the monitoring of air quality is developed and made available to the

public in accordance with the specific requirements of the relevant EU directives.

6.1.1. Monitoring network structure

The general structure of the monitoring network is presented on the website of the

monitoring network, accompanied by a cartographic description. Updates are

provided on request.

6.1.2. Monitoring station documentation

The comprehensive documentation of all stations of the monitoring network is carried

out in accordance with the requirements specified in the EU directives /1/ , /2/ and

comprises the classification and instrumentation of each station, their technical

description, as well as unit location plans in the scale 1:10.000 and photos of the

stations from different angles.

The documentation is made available to the public on the website of the monitoring

network. Updates are provided on request.

6.1.3. Measurement methodology and procedures

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The measurement methods and procedures used are presented and explicated on

the website of the monitoring network.

6.2. Evaluation standards

A complete overview of all applicable limit, target, information and alert thresholds

and of the long-term targets in accordance with the EU directives /1/ , /2/ is made

available on the website of the monitoring network.

6.3. Formation and effects of air pollutants

Detailed information for individual air pollutants with regard to

- characteristics

- causes of formation

- effects on health

- conduct recommendations in case of high concentrations

- possible reduction measures

is published on the website of the monitoring network.

6.4. Plans and Programmes

The plans and programmes that must be developed according to /5/ 2001/752/EC

are to be published in abstract and in full version on the Internet and, where required,

also in print.

7. References

/1/ Directive 2008/50/EC of 21 May 2008 on Ambient Air Quality and

Cleaner Air for Europe

/2/ Directive 2004/107/EC of 15 Dec 2004 Relating to Arsenic, Cadmium,

Mercury, Nickel and Polycyclic Aromatic Hydrocarbons in Ambient Air

/3/ Directive 2003/4/EC of 28 Jan 2003 on Public Access to Environmental

Information and Repealing Council Directive 90/313/EEC

/4/ Commission Decision 2001/752/EC of 17 October 2001 amending the

Annexes to Council Decision 97/101/EC establishing a reciprocal

exchange of information and data from networks and individual stations

measuring ambient air pollution within the Member States

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/5/ Commission Decision K (2004) 491 of 20 February 2004 establishing

the modalities for the dissemination of information concerning the plans

and programs related to the limit values for certain air pollutants

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III.A4: Reports, Statements,

Publications

1. Purpose

This procedure instruction regulates the course of action for the preparation of

reports, the issuing of expert opinions and statements, as well as for data publication,

on the basis of the results of measurements in the monitoring network.

2. Scope

These provisions apply to the reporting on online-acquired measured data and on the

results of the gravimetric determination of the concentration of the PM fraction in the

monitoring network centre of the air quality monitoring network.

3. Description

This chapter comprises a description of the regulations and procedures for the preparation of reports, the issuing of expert opinions and statements, as well as for data publication, on the basis of the results of measurements in the monitoring network.

Appropriate regulations and procedures ensure that

reports and statements are prepared and written in the adequate form,

well-established control mechanisms are in place before the transmission or

publication of measured data,

data publication is carried out in such a way as to be accessible to a wide

audience.

3.1. Preparation of reports, statements, and data publication

For the purpose of this document, preparation primarily refers to the reporting on the

monitoring of air quality. In addition to the continuous (daily) reporting on the

measured data collected in the monitoring network, separate monitoring reports are

prepared on fixed dates, on the basis of digital questionnaires. The monitoring

network centre is responsible for the preparation of these reports.

Provided that monitoring reports contain results from measurements that were performed by third parties, these results must be clearly flagged. If a monitoring report contains opinions and interpretations then the basis for these opinions and interpretations must also be included in the report. Opinions and interpretations must be clearly indicated as such in monitoring reports.

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3.2. Reports, statements and data publication

Reports are prepared on various matters in the field of pollution control. The most important requirements regarding the preparation of reports and statements and the publication of monitoring data are presented below. 3.2.1. Reports on air quality

Reports on air quality are generally addressed to the authorities, to the EU and to the

interested public. The subject areas covered by these reports are:

- analysis of air quality data according to the regulations in force (EU directives)

- annual reports

- monthly reports

- contributions to air quality maintenance plans and action plans

- evaluation of special pollution situations in the framework of special monitoring

projects.

As a general rule, these technical reports are drawn up by several authors and are

not signed. Before the preparation of the reports commences there is a consultation

regarding their content and form. Depending on the importance of each report, their

verification and release are the responsibility of the head of the monitoring network

centre or that of the head of the monitoring network.

The reporting can be carried out both in classical form (in print) and by means of data

storage media (e.g. CD-ROM) or in purely electronic form, on the Internet.

Section III.A3 ―Information of the Public on Air Quality Data‖ regulates more detailed

the preparation and issuing of the aforementioned reports.

3.2.2. Expert opinions and statements

Expert opinions and statements from the monitoring network span all the important

report forms:

- expert opinions on the pollution situation and its assessment,

- expert opinions in the framework of authorisation procedures,

- expert opinions in the framework of regional/spatial planning procedures,

- expert opinions on research and development projects and reports

- statements on requests from citizens in connection with ambient air pollution.

3.2.2.1. The standard structure of expert opinions and advisory opinions

Expert opinions and statements from the monitoring network comprise as minimum

content the following elements:

- task, cause and orderer

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- introduction

- research methodology

- research results

- assessment of results (optional)

- summary.

3.2.2.2. Verification and release

For the verification of expert opinions and statements, the ―4 eyes principle‖ is

applied. This means that every expert opinion / statement must be checked by at

least one other competent person before it is passed on.

This verification is normally carried out by transmission through official channels.

Depending on the importance of the expert opinion / statement it is passed on with

the addition ―to the head of the monitoring network before/after dispatch, as

notification/for co-signing‖

The addressees of such expert opinion / statement are usually the ministry, local

authorities, further regional or national authorities or other organisational units,

research institutions, courts of justice or private persons (citizens‘ requests).

3.2.2.3. Signature regulations

Expert opinions and statement are, as a rule, signed by the head of the monitoring

network or the head of the monitoring network centre, provided there are no superior

regulations stating otherwise.

In such cases the author of the expert opinion / statement is to be named as

rapporteur.

3.2.3. Internal reports

For the purposes of this document internal reports are reports that serve exclusively for the circulation of information within the monitoring network. The preparation of internal reports is a consequence of the necessity to circulate specific information, which is available in only location site initially, but which is needed in other points of the monitoring network as well. The information should generally be circulated in a timely manner. In the cases where the transmission of information or the failure thereof can have a direct effect on data publication (or other effects) information must be forwarded without delay. As a general rule, internal reports shall be prepared in writing, for reasons related to documentation and verification. Appropriate forms shall be drawn up for the routine transmission of information, indicating, among other things, the order of recipients in the information chain. This can vary depending on the type of information

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disseminated. The receipt of the information is to be documented by means of a signature and date on the form. Subsequently, the information is passed on without delay, according to the list of recipients. 3.2.4. Data publication

Data publications, on the basis of results from measurements in the monitoring network, takes place both in classical from, as an essential part of reports (see reports) and in purely electronic format, on the Internet. The subjects of data publication are in principle only appropriately checked, validated measurements results (cf. section III.A2). This guarantees that no erroneous data reach the public. If at the time of publication final validation has not yet been carried out, this must be indicated in an appropriate manner (see the next step). This applies in particular to the routine hourly/daily public information. According to the legal requirements regarding the timely information of the public, only unchecked or preliminarily checked data can be made available on the Internet in a timely manner. The publication of such data is consequently accompanied by the following notice to the recipient: ―The measured data have been checked automatically but they have not gone through the whole validation process. They are subject to change. Further information is available on request.”

If data publication comprises results of tests that were carried out by third parties,

these results must be clearly indicated as such.

Section III.A3 ―Information of the Public on Air Quality Data‖ regulates this subject

more detailed.

3.2.5. Data provision on demand

The monitoring network prepares, upon request, special data compilations and analyses for authorities, scientific institutions, associations, companies and, in particular cases, also for private persons. The requests shall be checked according to the criteria specified in Section III.A5 ―Handling of External Requests on Air Quality Data‖ before being processed. The responsibility of checking the requirements for accepting the request and of documenting this verification procedure, including potential changes that may result from clarification discussions, rests with the head of the monitoring network.

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After this check has been completed and a positive decision taken, the application is forwarded form the head of the monitoring network to the head of the monitoring network centre.

Section III.A5 ―Handling of External Requests on Air Quality Data‖ regulates this

subject in more detail.

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III.A5: Handling of External

Requests on Air Quality Data

1. Purpose

In implementation of the EU directive regarding information on environmental matters

and the national law regarding information on environmental matters, the monitoring

network provides, in addition to the continuous information for the public, special data

compilations and analyses, upon request. Such requests usually come from

authorities, scientific institutions, associations, companies and also from citizens.

This procedure instruction describes the basic procedures for answering external

data requests and defines the related responsibilities.

2. Scope

These provisions apply to the provision of online-acquired measured data and of

results from gravimetric determination of the concentration of the PM fractions in the

monitoring network centre of the air quality monitoring network.

3. Procedure description

3.1. General provisions

In order to ensure that applications are processed in due time, it is essential that the uninterrupted

information flow within the monitoring network be guaranteed.

In accordance with the responsibilities, data requests that are not received by the head of the monitoring

network shall be promptly transmitted to him/her for information and verification.

3.2. Verification of requirements for accepting the request

The responsibility of checking the requirements for accepting the application (external

data request) and of documenting this verification procedure, including potential

changes that may result from clarification discussions, rests with the head of the

monitoring network.

Before accepting and processing external data requests a check is required in order

to ascertain whether:

the desired data are available,

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these data meet the quality requirements for the intended purpose,

special assessments and interpretations requested are possible,

technical and staff resources for the processing of the application are

available.

After this check has been completed and a positive decision taken, the application is forwarded from the head of the monitoring network to the head of the monitoring network centre.

3.3. Application processing (data provision)

After receiving the application, the head of the monitoring network centre decides on

the further course of action and on the involvement of further staff members in the

processing of the application.

If the request regards the mere provision of measurement data – this includes the

regularly requested routine data provision to authorities and institutions – then it can

be dealt with by the responsible staff member.

After completion of the assignment and before the data are sent out to the orderer,

the head of the monitoring network centre must be informed about the result of the

processing of the application. He is responsible for the verification and release.

After the release if approved, the employee responsible can send the data to the

orderer. The provision of data must be documented (outgoing mail).

If the release cannot take place, the responsible employee must be informed

immediately as to why the data cannot be released. The head of the monitoring

network centre shall ask for corrections to be made in case this is necessary. The

corrected result shall be once again submitted to the head of the monitoring network

centre for verification and subsequent release.

If the request entails more than the provision of measurement data (e.g.

assessments of pollution situations) the application is processed by the head of the

monitoring network centre, with the participation of further employees if necessary.

After completion of the assignment the head of the monitoring network must be

informed about the result of the processing of the application. The responsibility of

verification and release of the assignment rests with the head of the specialised

department. Once the release has been approved the data can be provided to the

orderer by the head of the monitoring network centre. The provision of data must be

documented (outgoing mail).

Documentation of Corrections after the Calibration – Year / n

Date of calibration year/n Date of data control

Station 1

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Station 2

Station 3

…

….

…

…

…

Indication of d in each unit that the component has in the database.

Period of time of the correction

Station/Compone

nt

Start End kA kE dA dE executed

STAT1/Comp1 yyy.mm.dd yyy.mm.dd c1 c2 d1 d2 yyy.mm.dd

….

….

…..

VARIAN ICP-MS „820“: Mass-Spectrometer with Inductive Coupled Plasma

Content

6.1 Gas supply .............................................................................................................. 283

6.2 Exhausted air supply .............................................................................................. 283

6.3 Daily starting up the operations ............................................................................. 283 6.3.1 Starting the steering software ................................................................................................. 284

6.3.2 Control of the instrument status .............................................................................................. 284

6.3.3 Production of vacuum ............................................................................................................. 285

6.3.4 Ignitiation of plasma and open the „Gate Valve― ................................................................... 285

6.3.5 Plasma Align .......................................................................................................................... 286

6.3.6 Mass calibration of the quadruple........................................................................................... 287

6.3.7 Detector Setup ........................................................................................................................ 287

6.3.8 Detector-calibration ................................................................................................................ 288

6.4 Structure of the measurement sequent (Worksheet)............................................... 288 6.4.1 Select the analyze method ...................................................................................................... 288

6.4.2 Development and processing of the method ........................................................................... 289

6.4.3 Introduction of sample list and calibration standards ............................................................. 289

6.5 Carrying out the calibration .................................................................................... 290

6.6 Sample analyze ....................................................................................................... 291 6.6.1 Assembly of moving needle ................................................................................................... 291

6.6.2 Start the analyse with the moving needle ............................................................................... 292

6.6.3 Checking the measurements during the analyze ..................................................................... 292

6.7 Switching off the devices ....................................................................................... 292

6.8 Data protection and turn off PC ............................................................................. 293

7.1 Overview over routine service and maintenance ................................................... 294

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7.2 Sample introduction system ................................................................................... 294

7.3 Interface .................................................................................................................. 296

7.4 Change the Ar-Gas supply ..................................................................................... 296

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1 Identification

ICP-mass spectrometer „VARIAN ICP-MS 820“ (Fa. VARIAN) with automatic moving

needle (SPS 3) and cooling device (Typ 142-R102 Son. wa-wa)

2 Appliance area

This SOP is applied for VARIAN ICP-MS 820 device, which is produced by Firma

VARIAN, and the elements are in water solutions (digested samples of solid substances like

water samples) analyzed with.

3 Scope

This SOP regulates the command, function controll and service of the ICP-MS-device.

Further on are indications on security and labour protection.

4 Terms/Abbreviations

ICP-MS Mass spectometer with inductiv connected plasma

Auto sampler device for automatic sample injections

DL Bureau head

AL Head of department

GV Responsible for devices

MA integrated staff

Verantw. Gas Responsible for gas provide

IT-Admin IT-Administrator

RSD relative standard deviation

IDL instrumental detection limit (instrumentel detection limit)

5 Responsabilities

Activity Responsible Co-action Information

System configuration IT- Admin GV, DL MA

Configuration of network cards IT-Admin GV DL

Swich on and off the systems MA

Device unblocking resp. blocking GV DL

Routine service GV DL

Another service and maintanace

operations agreed with the technical

service

GV DL AL

Establishing the measurement and

evaluation methods GV MA DL

Establishing and finalizing the sequent MA

Control the Ar-, H- and He-gas

providing GV MA

Change of the Ar-battery or bottles respons. Gas GV

device responsible for this device were set: …..

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6 Description

System VARIAN ICP-MS 820 is operated under normal operations in Peak hopping-Modus

(Quadruple analysis only the matter of the resp. isotopes) and consists of more parts:

- One sample entry unit, one ion source, one interface, one matter analyzer incl. ion

optic, one detector, one high vacuum pump unit with more vacuum pumps and water

cooler.

- Controll computer with printer,

- One auto sampler SPS 3 for automatic completion of the sample sequent.

All components are standard related; solid connected with eachother and are controlled as an

unit.

6.1 Gas supply

Argon is necessary for operating the devices (Quality mind. 4.6). Three argon streams are

flowing through the concentric hoses of the torch unit, plasma gas with ca. 18 l/min, auxiliary

gas with 1,6 l/min and spray gas with 1 l/min. The initial pressure of Ar must be between 6

and 8,3 bar.

For minimizing the disturbing interferences through matrix elements, it can be supplied H or

He as so called CRI-Gas in the field of CRI („Collision Reaction Interface―). The purity rate

conducts also a min. 4.6. It is necessary a 2,75 to 4,8 bar. The gas stream is flowing during

feeding in from 50 to 100ml/min.

6.2 Exhausted air supply

For cooling and discharging the hot plasma gas steam are necessary two closed exhausted gas

channels.

Channel 1:

This air stream (hose diameter 150 mm) will be conducted through an instrument and it is

used as heat discharger. The minimal aspiration performance is 8,5m3/min. A value below the

minimal value is leading to an immediately switch off the pumps and plasmas, if necessary.

Channel 2:

This air stream draws the pollutants from the plasma chamber (plasma cabinet). Here is

necessary a minimal draw performance of 3-4 m3/min. A value reached below the minimal

value leads to an immediately switch off the plasmas.

6.3 Daily starting up the operations

- Open the gas and the cooling water supply (primal water supply) at the wall fittings.

- Afterwards control of the initial pressure:

o Ar-gas initial pressure at the wall fitting must be between 6 and 8,3 bar.

o Initial pressure of H and He at the wall fitting must be between 2,7 and 4,8 bar.

o Initial pressure of the cooling water at the wall fitting must be at least 3 bar.

- Ventilator switcher 3 must be put on „on― at the entry door.

- Control oft the fill level of the stock bottles:

o If necessary filling the storage bottle for the washing processes of the auto

samplers

(if quantity < 1/3)

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o If needed 0,5-Liter bottle (daily new) for dilutions with a calibration-blank-

solution (KBL, acidified de-ionized water; Lf < 0,055 µS/cm).

o If necessary, (if a quantity < 1/3) filling up the storage bottles for an internal

standard.

- Start the cooling device and control the temperatures (target: 20 °C; actual: after a short

run-in period 20±2 °C).

- Switch on the auto sampler (waiting for the initializing period)

- If necessary switch on the VARIAN ICP-MS 820 on the green push button at the front

field. (Usually the device is already in a stand by modus with running pumps). It is no

need to be switched on. Pumps will be switched off only during the measurements breaks

that last more than 3 days.)

6.3.1 Starting the steering software

- Switch on the PCs.

- In the identification window with user name and pass word entry.

- Steering software „ICP-MS Expert―when double clicking on the open symbol.

- User name and password in the dialog field to establish the access to ICP-MS-Expert-

Software

The opened window constists of three round basis acces surfaces:

1. <Worksheet>

2. <Instrument>

3. <Exit>

The symbols are on the top frame.

6.3.2 Control of the instrument status

The window „Instrument Status‖ opens by pushing the shift button and by simultaneous

clicking of the button <Instrument>. Under the label <Status> all the important instruments

parameter and instruments status can get controlled.

There are status indicators and current values. Both are gathered on the right side of the

group.

Status-Indicators:

The status indicators „light‖ green, red or grey.

Indicators, that are red „lighter―, indicate a failure that has to be removed before work can be

continued.

Green indicators signal no failure.

Grey indicators show that the respective equipment/component partial is out of work. It is no

failure.

The importance of the respective indicators will be found by searching the word ―status page‖

in the manual of the ICP software.

Current values:

Current values offer information about pressure, temperature, HF-performance or pump rate.

They are not allowed not to meet specific target values resp. to go below or above stipulated

thresholds.

In the followings there are given important thresholds and targeted values:

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Equipment/Medium Target

value

Threshold Admitted deviations of the targeted value

RF-Generator 1,4 kW - (set value)

Temperatur of the spray chamber (automatic start only after measurement start)

3 °C - +/- 0,5 grd

Peristaltic-Pump rate 7 rpm - (set value)

Cooling water

temperature

20 °C - +/- 2 grd

Rotary Chamber Temp. 20 °C <30 -

Instrument-Temp: 20 °C <34 -

Pre-vacuum - p < 10-3

Torr -

High-vacuum before Plasma-Start

- p < 5*10-6

Torr -

High-vacuum after Open Gate Valve

- p < 2*10-4

Torr -

High vacuum during the

measuring

- p < 1*10-2

Torr -

Note: Compliance to the given thresholds and target values must obvious be fulfilled only

after the proper equipment/medium is activated. That means that the status indicator on the

left side has a green „light―(grey means not active). This could mean that, for example, when

vacuum has not started to run (grey) the pressure value will be not displayed.

Indication: The instrument status must be also controlled after finalization of 6.3.3

und 6.3.4. This should be controlled many times also during the daily routine

activity.

6.3.3 Production of vacuum

The vacuum pumps should remain in use if ICP-MS is operated having only short breaks up

to three days operating time.

If the vacuum pumps don‘t work (no noise, no vacuum pressure), than to put them to work

have to be proceed as follows:

- At the steering -PC click on the symbol where <Vacuum> is written, on the top of the

status bar.

- The vacuum pressure is displayed on the window <Instrument Status> down, on the right

side. The lower value (High - vacuum) must display a pressure p< 5*10-6

Torr. Only after

that can plasma (6.3.4) be ignitiated.

-

6.3.4 Ignitiation of plasma and open the „Gate Valve“

- Click on symbol, where below <Plasma> is written, on top of the status bar.

- Untight pump hoses will be placed at the Peristaltik Pumps and tensioned. Afterwards

flaps will be pushed and tensioned.

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Indication: Check that no back liquid (puddle) will be formed in the spray chamber.

- Checking the running around Peristaltik pumps:

a) counter not is not allowed to be loose,

b) pay attention to the isolation of the hoses and

c) to the even liquid transport.

d) no air blister in the hoses is allowed.

- If a failure notification is appearing and plasma hasn‘t started yet, it will be „o.k.―

confirmed and the start will be repeated.

- If the plasma start is unsuccessful after several attempts than the device responsible should

be informed.

- In order to get a steady conditions of plasma stream and vacuum, the „Gate Valve―will be

opened. This will happen under <Actions>, <Gate Valve open>. The process takes about

3 Minutes.

Important: For stabilizing the plasma and vacuum it has to be waited at least 45 min to

analyze start.

6.3.5 Plasma Align

During the stabilisation phase of the devices, the „Plasma Align― can be carried out. Herewith

the VARIAN-test solution TS5 will be necessary (5 µg/l of the elements with the Isotop Be9,

In115, Pb208, Ce140, Ba138, Th232)

If necessary, open again <instrument status>: <Shift> + <Instrument>. Select label.

The sample draw hose will be separated of the auto sampler and dipped in the VARIAN-test

solution. After that, the Peristaltik pump will spin rapidly about 10 sec (with <Peristaltic

Pump On Fast>; after 10 sec <Peristaltic Pump On>). Hier are two routines possible: (“Time

Scan” and “Automatic Alignment―)

a) Time Scan

Time Scan is for handling the representative signal course.

For this select „Scan Type― <Time> (below, left) and click on <Start>. In the next

window select <Manual Sample Introduction> and start with <Read>.

Now the signal processes for the representative isotop (Be9, In115, Pb208), oxidation

rate (Ce140 O16) and multiple charges (Ba138++) can be followed.

After a run-in period of 1 minute, next target values will be reached:

Be9: c/s > 1*104

In115: c/s > 3*105

Pb208: c/s > 1*105

Ce140 O16: ratio < 4*10-2

Ba138++: c/s < 3*10-2

At strong deviations of the target values (+/- 10er-Potenz) and variations of the signal

course, the device responsible will be informed while the „Plasma Align―is still going.

Routine analysis is not allowed.

„Plasma Align―should be watched for about 5 minutes. (steady signal courses without

heavy variations, having a constant average value)

It will be finalized with <Stop>.

b) Automatic Alignment

„Automatic Alignment― is for the optimal positioning of the plasma related to the

opening of the Sample Cone. Only if necessary, this will be carried out in justified

cases (for ex. after changing the torch, after working at the Cones etc.).

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Select Scan Type― <Automatic Alignment> and click on <Start>. In the next windows,

select <Manual Sample Introduction> and start with <Read>. Positioning process runs

automatically and will be automatically finalized.

If 6.3.6 - 6.3.8 will be not carried out, than the sampler draw hose will be again connected at

the auto sampler.

6.3.6 Mass calibration of the quadruple

The quadruple has to be weekly calibrated. This is also carried out with a VARIAN (TS5)

testing solution.

For this click on <Status> label <Mass Cal>.

For a fast aspiration of the testing solution, the Peristaltik Pump will be spinning quickly

approx. 20 sec. This is under <Pump>, <Peristaltic Pump On Fast>. After 20 sec, the pump

returns on <On>.

By clicking on the button <Start> it opens the window, where the manual solution

introduction will be selected (Manual Sample Introduction).

With <Read> starts the calibration process.

After finishing the procedure (approx. 2-3 min) the notification „Mass Calibration Passed― is

appearing.

If the calibration wasn‘t successful (error notification), „Resolution and Trim―must be next

carried out. For this click on the same named label. This goes at the same time with the

VARIAN-testing solution.

After a successful „Resolution and Trim― the <Mass Calibration> will be repeated. At this

time, this should be carried us with success.

If after sever repetitions, the mass calibration is not successful, than the device responsible

should be informed.

If no. 6.3.7 - 6.3.8 will not be carried out, than the sample suction hose will be connected

again at the auto sampler.

6.3.7 Detector Setup

Advice: only by the device responsible or test director to be carried out!

- the „Detector Setup― should be run every 3 months. On the right, below, in the window

<Detector Setup> the time of the last „Detector Setup― is to be seen.

- By fitting the curve, the best tension of the detectors will be found.

For this click on the window <Status> label <Detector Setup>.

The sample suction hose will be separated from the auto sampler and dipped in the VARIAN

(TS5) testing solution.

For a faster suction of the testing solution, the Peristaltik pump will quickly run for about 20

sec.

This is under <Pump>, <Peristaltic Pump On Fast>. After 20 sec the pump will be put again

on <On>.

Now should be entered the detector – tension field, that would be gone through it, (1500 V -

3000 V).

By clicking the button <Start> (left bellow) opens the window, where the manual solution

introduction (Manual Sample Introduction) will be selected.

With <Read> starts the Setup-process.

After ending the procedure (after few 2-3 min) appears the notification „Optimal Detector

Voltage has been found―. This notification is confirmed with OK.

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The new determined detector tension is specified in yellow in„Detector Voltage―. After the

evaluation of the curve course and comparison to the determined detector tension, the new

tension can be taken with <Apply>.

If the no. 6.3.8 is not carried out, the sample suction hose will be connected to the auto

sampler.

Note: if the detector works in „Medium-„ or „High-Modus―, the attenuation factors must

be determined again under <Detector Attenuation> after the detector tension was

modified. (no. 6.3.8).

6.3.8 Detector-calibration

For the detector 4 settings are possible that can be related to the attenuation:

„non― (no attenuation)

„Medium― (average attenuation)

„High― (high attenuation)

„Auto― (automatic attenuation)

These settings can be selected separately for every isotop to be measured. The settings „non―

and „Auto― can be selected without any further steps.

„Non― and „Auto―are sufficient for the measurement for water and dust to be carried out in

dec. 620. For the settings „Medium― and „High― the determinations of the attenuation factors

are necessary. This procedure is described in the manual on page 28.

6.4 Structure of the measurement sequent (Worksheet)

Further explanations are to be found in manual on page 30ff.

6.4.1 Select the analyze method

For the selection of the analyze method are two possibilities:

- a) Open one completed or already measured worksheet, save under new names and delete

the measurement values. Save again afterwards. Deleting the measurement values of the

selected „Worksheet― can be done under <Edit> and <Delete Worksheet Data>. In this

way the worksheet is without measurement values and without modifications of all the

parameters and settings.

-

- b) Select a template and save it under the new name as worksheet.

<File> and <New from Template>

It opens the window „Select Template― (standard list is C:\Programme\Varian\ICP-MS

Expert\Run\Template\). There can be achieved one adequate template. The confirmation

with <OK> leads to the window where the name of the worksheet to be established

must be entered. Also the location for saving can be selected. With <Save> follows the

saving of the new worksheet.

- The parameters settings in the worksheet have to be controlled before analyze begin

(calibration incl. measurement) and if necessary to correct them.

- It is important to underline that every worksheet consists both method settings and

measurement values.

Methods and measurement values will be saved in one file.

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6.4.2 Development and processing of the method

In one method (Worksheet) can be established several so called „ „Condition Sets―. These can

differ from one another in almost all method settings (isotop selection, type and quantity of

the sheatgases, optimization parameter, dwell time, attenuation, etc.). The settings resp. the

calibration standards apply for all „Condition Sets― of the worksheet.

Note: By carrying out the analyze with <RUN> these „Condition Sets― will be completed one

after another from top to the bottom for every measurement solution.

To process the method is possible under <Method> - <Edit Method>.

Labels will be done one after another:

For every „Condition Set― of a Worksheet the following settings are possible:

<Element>: The measured elements/isotop can be here introduced or removed.

Further on is the possibility to select the used Sheatgas.

<Optimization>: The method parameters can be set here.

<Standards>: Setting the calibration standards to be applied (it is identical for

every „Condition Set― of the worksheet)

Input of information related to the quality assurance:

- minimal quality of the correlation coefficient of

- maximal error in %

- calibration linear through the zero point?

<Scan Settings>: Setting the „Dwell time― (counting in µsec each Scan) and

„Attenuation― (isotop specific attenuation of the detector).

<QC Tests>: Setting the critical values that lead to automatically ―handling‖ of the

devices or generate flags behind the measurement values when

values are exceeded. The instrumental detection limits for example

will be introduced for every isotop.

Using Sheatgas, the eventual correction equations have to be eliminated in the

isotop settings.

At routine measurements with in SOPs procedures described methods are modifications of

settings to be done/ carried out.

6.4.3 Introduction of sample list and calibration standards

- The entries are under card <2. Sequence>

- Here are the 4 most important columns to be found.

- Rack#Hose: Position in Auto sampler

- Sample Label: Identification of the sample

- Type: which type of solution (sample, standard, ...)

- Dilution Factor: dilution factor of the measurement solution

- As help tool for selecting the Racks and the setting of the measurement sequent are used

both connect surfaces on the right limit of the image: <Sampling Setup ...> und

<Sequence Wizard ...>.

- Next will be the necessary steps described:

<Sampling Setup ...>

Here comes the selection of the type and number of racks. Further on can be set the

locations of the calibration standards and samples. The sites of the measurement

solutions in the auto sampler can be also seen in the image.

< Sequence Wizard ...>

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The Sequence Wizard leads through the setting of the measurement sequent.

a) Introduction of the sample number <Next>

b) <Analytical Calibration>: here settings related to the structure of the

measurement sequent are to be fulfilled. For ex. depending on how many

samples after, a recalibration is taken place, ... <Next>

c) <Calibration tests>: Here is to stipulate, which type of test during

calibration has to be done. <Next>

d) <Sample related Tests>: Here is to stipulate which type of test has to be

carried out during the sample measurement. <Next>

e) <QC Tests Order>: <Next>

f) <Summary>: Here will be again listed all stipulated conditions from a) to

e). <Finish>

A new established and proved worksheet can be saved as new template for future

measurements:

<File> <Add to Templates>

A window is opening where the name of the new template, saving location and important

notes can be inserted.

6.5 Carrying out the calibration

- Calibration is before analyzing of samples.

- Initial condition for calibration is the presence of an open worksheet. In the following

explanations will be considered that in this worksheet are inserted the standards according

to the procedure at no. 6.4.3.

- At the locations of the auto samplers settled in the worksheet (Rack#Hose), the calibration

solutions have to be inserted with the corresponding concentrations.

- Under <3. Worksheet> the solutions to be measured (locations in auto sampler) has to be

selected on the left limit (colored in yellow).

- With <RUN> opens the window that shows to the „unclear information‖ (for ex. several

marked samples). This would be confirmed if everything is o.k.

- Now the device is carrying out the calibration automatically.

- After analyzing the calibration standard solutions, the calibration linear and the calibration

coefficient must be checked for every measured Isotop. This is automatically made by the

software according to the given information in 6.4.2 <Standards> and have deviations in

the red step.

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Fig. 1

- If the notifications „Mass Scan―, „Calibration― and „Status Block― are not appearing on

the desktop, by double clicking the field of the measurement value or under <View> by

inserting the tick at by <Mass Scan>, <Calibration> and/or <Status Block> than open

these missing windows. If in the column of a isotope a single box is marked a single box,

afterwards on the right side, bellow, are appearing the calibration linear and the interesting

values of the calibration as for ex. correlation coefficient.

6.6 Sample analyze

6.6.1 Assembly of moving needle

- In Rack 1 on the first place 1 is KBL.

- Like the registration on the sample list and moving needle assembled as presented in

image 2; 6 samples in 50 ml PP tubes suit to Rack 1. 60 samples in 20 ml PP-tubes suit

each on Rack 2 to 4.

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Fig. 2: Example of an Auto sampler assembly

6.6.2 Start the analyse with the moving needle

- First the analyzed field will be marked under the card <3. Worksheet> (colored in yellow)

- With <RUN> opens the window, that indicates again towards „unclear information―(for

ex. multiple marked samples). This will be confirmed, wenn everything is o.k.

- When analyze is running through the Auto sampler, the sequent will be independent

worked out from the device after activating <RUN>.

6.6.3 Checking the measurements during the analyze

In case of sample results located above the measurement field, dilutions with KBL must be

carried out and analyzed afterwards. Herewith sample (places) (no. 6.4.3) can be attached

during the current analyze.

- After the analyze sequent is finished, a new sequent for the diluted samples can be

achieved (see no. 6.4.3).

6.7 Switching off the devices

- The measurement values will be automatically saved in a current worksheet. That‘s why it

is not necessary to save completely.

- After last sample, plasma will be left on for about 10 minutes, so that the torch and the

spray chamber will be cleaned by transporting the KBL.

- Afterwards plasma delete: click on <Plasma> in the upper row and und confirm „Shut

down Plasma?“ using <Yes>.

- All the gas and exhaust air settings will stay first unmodified.

- Loose hoses of the both Peristaltik pumps.

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- If the next measurement is first planned after more than 3 days, vacuum can also be turned

off. This is done under <Vacuum> with final response of the question „Shut down the

Vacuum System?― with <Yes>

- ICP-MS-device is running on continuously, if Vacuum wouldn‘t be turned off, (Stand-by-

Modus).

- Turn off the cooling device.

- In at least 10 Minutes after turning off plasma and/or vacuum, all open gas and water

fittings must turned off.

- Control the litter bin on the floor: if necessary, discharge in the sink (proceed through the

acid neutralization).

- Evacuate sample rests accordently and clean the sample tubes according to the test „620-

P-ICPMS_W― or „620-P-ICPMS_S―.

6.8 Data protection and turn off PC

Indication: data is automatically protected on the worksheet and can be seen, copied,

printed or exported anytime by opening the worksheet.

- Preparing the measurement data for copy in EXCEL:

Behind some measurement values the so called flags can be found. This it links to

certain data.

Frequent flags are:

r carrying out ulterior modifications

b bellow detection limit (IDL), pre-set: IDL=1

x outside the calibration field

! Carrying out multiple measurements

First of all the flags have to be removed for getting a simple copy of the data:

Under <Options> - <Preferences> in window „Solution Measurement Flags―the first

column will be deleted. (The column will be again inserted after copying data in

EXCEL.) Confirm process with <OK>. This „#―remains.

- Measurement values can be marked now with the mouse including table header and

sample definition. Click on right mouse button and <Copy> the marked field.

- Open an new empty EXCEL-folder and insert in both files „primal values― and „proceed

values ―.

- Save EXCEL-folder under the same name in the same list of the worksheet.

The processing of data take place on the sheet „processed values ― in EXCEL-folder. First

„#―will be eliminated. Pay attention that the decimal place does not slip!

Re-insert the flags in the ICP-MS-Software

Now, first column will be again inserted under <Options> - <Preferences> in the

window „Solution Measurement Flags―. The column with the flags will be extracted

out of the worksheet „Solution Measurement Flags― from the table EXCEL „Info for

dust and water measurements.xls―.

- Program „ICP-MS EXPERT― and „EXCEL― are completed and PC turns off.

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7 Periodic control and maintenance operations

7.1 Overview over routine service and maintenance

Next table offers an overview on the temporal range and type of necessary routine

service and maintenance.

Yearly:

Carrying out prevention maintenance by a qualified Varian

Service Engineer.

7.2 Sample introduction system

For a reproducible and correct measurement, the sample introduction system has a great

importance. Failure of this field must be kept as little as possible.

Sampler introduction system consists of following parts:

• pump hose

• three-channel pump

• micro-concentric sprayer

• Peltier-cooled spray chamber

• sheat gas adapter

• torch

Checking every part and failure causes

Daily

Control Argon stock

Control

Control litter bin and discharge if necessary Argon initial pressure 5 – 6.0 bar

Control pump hose and change if necessary Isolation and deformation

After torch exchange, setting the torch position with

Weekly

Control

Carrying out the mass calibration with Control torch and clean if necessary. On deposition on the exterior of the

tube and on the injection tube

Control cone and clean it if necessary Deposit on cone Control sprayer and clean if nec. Spray performance Spraying chamber, check and clean Deposit and precipitation

Pump control Oil level and eventual leakage

Monthly

Control induction coil

Water cooler

Keep clean device surface

Control

deformation Water level Dust

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Sprayer:

Function capacity of the sprayer can be checked at the run time, when the cover cap

of the spray chamber will be removed and the mist formation in the spray chamber

will be checked.

Torch:

When plasma goes out directly, ignition problems are coming up or RSD of the

multiple measurement are going worse, the cause of all this can be the crust

formation or the damaging of the torch.

Pump hose:

Pump hose must be changed when obstructions, leakage are showing up or when

the RSD of the multiple determination is getting worse.

Peltier-cooled spray chamber:

In an ideal case, the course of the drops can be watched as a thin layer. No thick

drops have to be seen on the chamber wall. The current temperature must be

correlated to the set target temperature (for ex. 3 °C).

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Operations, that are possible to be done on that part, are explained in manual beginning with

page 3. These have to be carried out only by the device responsible or testing adviser.

Part Working gang Page in manual

Torch

Remove the torch 3

Clean the torch 4

Use the torch 5

Sheat gas adapter &

Spray chamber

Mount and dismount and

clean the sheat gas

adapter

7

Spray chamber

Mount and dismount and

clean the spray

chamber

8

Sprayser

Mount and dismont the

sprayer 9

Clean the sprayer 10

Pump hose Use / change the pump hose 12

7.3 Interface

Ions are transferd by means of plasma in the mas spectometr. The interface consists of two

water cooled cones, one so called „Sampling―-cone and one „Skimmer―-cone where a vacuum

field (expansions chamber) between is between them. Cones have each a circle port with a

diameter of 0,3 to 1mm. From the central part of the plasma, one part of the gases that contain

ions is run through a „Sampling―-cone into an expansion chamber. The central part of this

stream will be led through the port of the „Skimmer―-cone in the vacuum of the lenses

system.

Therefore interface represents the transfer between the sampler introduction from outside and

vacuum field of the mass spectrometer.

Changes can occur during the routine operations and failure of the measurement procedure

can appear.

This is the reason why a periodic control and cleaning of the cone is necessarily.

The possible operations at the cones are presented with details in the manual on the pages 13

– 17. These are only by the device responsible or test adviser to be carried out.

Indication: For routine operations, a reserve torch and a reserve cone must be kept on

stock. When a part of it will be cleaned, this can be changed immediately with a new

reserve part.

7.4 Change the Ar-Gas supply

(External; can take place by running device)

see „service instructions for the gas bottle instalation “

Indication: Valve movements must be slowly carried out, so that the manometer won‘t

get damages.

- When gas pressure of the battery is going under 25 bar, a new battery has to be ordered. If

the rest pressure is going down to < 12 bar, automatically will be switched over connected

to an open reserve bottle.

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- Hand screw with a black arrow is manual rotated, so that the arrow towards reserve bottle

shows.

- After that, the Ar-battery will be closed and opened at the station.

- From now on, empty battery can be changed for a filled one by a gas provider.

- After the new battery has be placed at the location, the port cap will be removed an the

station will be connected.

- Rotate main connecter of the battery.

- Open the proper washing gas valve and ventilate three times

- Turn the reserve bottle again manual on the full Ar-Battery.

8 Belonging documentation

User manual of VARIAN ICP-MS „820―:

Determination of trace elements and dust deposit

Content

1 Definition of procedure .......................................................................................... 299

2 Appliance area of procedure ................................................................................... 299

3 Scope of procedure ................................................................................................ 299

4 Basics of the procedure .......................................................................................... 299 4.1 Measurement principle ........................................................................................... 299

4.2 Terms and abbreviation .......................................................................................... 299

5 Reference to valid standards .................................................................................. 300

6 Devices (and auxiliary agents)................................................................................. 300

7 Chemicals ............................................................................................................... 300

8 Processing .............................................................................................................. 301 8.1 Sample handling ..................................................................................................... 301

8.1.1 Dust filter (STLV) .................................................................................................................. 301

8.1.2 Dust deposit (STND) .............................................................................................................. 301

8.2 Calibration .............................................................................................................. 301 8.2.1 Basic calibration ..................................................................................................................... 301

8.2.2 Routine calibration ................................................................................................................. 301

8.2.3 Ten point-calibration .............................................................................................................. 302

8.3 Measurement and evaluation .................................................................................. 302 8.3.1 Measurement .......................................................................................................................... 302

8.3.2 Evaluation ............................................................................................................................... 302

8.4 Disposal .................................................................................................................. 303

8.5 Declaration and storage of results .......................................................................... 303

9 Quality assurance ................................................................................................... 303

10 Belonging documentation ...................................................................................... 304

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1 Definition of procedure

Determination of trace metal content (SM) in dust form ambient air after microwave

disintegration of filter and dust deposit sample using ICP-MS.

2 Appliance area of procedure

The procedure is applied for the determination of SM in very small concentration contained in

particulate matter and dust deposit, which are collected on filter or in Bergerhoff containers

from the ambient air during the air quality monitoring.

3 Scope of procedure

Determination of participation of dissolved trace metals in disintegrated dust samples,

a) disintegrated PM10-Fraction of the particulate matter (STLV),

b) disintegrated dust deposit (STND)

4 Basics of the procedure

4.1 Measurement principle

The sample solution will be pulverized, formed aerosol transported in a plasma and the

isotope atomized and ionized. After straining the interface, formed ions are getting to

the quadruple (mass filter) using electrical equal and changing fields over the ion

optic. A selection of the accelerated, counted isotope type is taken place. The

registration of each Quadrupol straining ions is carried out in the discrete- Dynod-

Electron- multiplier (detector).

4.2 Terms and abbreviation

Ultra pure water (RW)

Calibration blind values (KBL)

Initial solution (SL)

Prefabricated calibration initial solutions (KSL_...) 1)

Calibration standards (STD......) 1)

Standards for ten point calibration (ZPK......) 1)

Internal standard initial solution (ISS)

Internal standard capture solution (ISA)

Standard reference material (SRM)

Qulity control solution (QK)

Calibration standard (STD)

field-blank value (field-BW)

Laboratory-blank value (Laboratory-BW)

Procedure blank value (Procedure-BW)

.

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5 Reference to valid standards

- DIN EN 14902 (October 2005): ambient air characteristics – standard procedure for

determination of Pb/Cd/As/Ni as component of the PM10-Fraction of particulate matter;

EN 14902:2005

- VDI 2267, part 15 (November 2005): substance determination for particles in the

ambient air; measure of the mass concentration of Al, As, Ca, Cd, Co, Cr, Cu, K, Mn,

Ni, Pb, Sb, V and Zn as component of the dust deposition using mass spectrometry

(ICP-MS)

- DIN 38402 (Mai 1986): Calibration of analyze procedure, evaluation of analyze results

and linear calibration functions for the determination of the procedure factors (DEV A

51)

- DIN 32645 (Mai 1994): Chemical analytic – detection limit, collecting limit and

determination limit – determination under rerun conditions; terms, procedure,

evaluation

6 Devices (and auxiliary agents)

For quality relevant working steps for ex. using control and calibration standards, carrying out

the sample dilutions, tested (red point labeled) pipettes will be used.

ICP-MS-unit (with PC, cooling mobil and Auto sampler),

50 ml PP-tube for the auto sampler ICP-MS,

20 ml PP-tube for the Auto sampler of ICP-MS,

Sample racks [1 pieces a 6 PP-tubes (50ml), 3 pieces a 60 PP-tubes (20ml)],

Pipettes (tested): 10µl-100µl; 100µl-1000µl; 1000µl-5000µl for dilution of samples above the measurement field and for production of calibration succession,

PFA-bottle (1000ml) for ISA

PFA-bottle (500ml) for KBL as washing solution

PFA- bottle (500ml) for manual sample dilution using KBL

PFA- bottle (500ml) for RW

PFA-volume flask (100ml) for KSL_...

Sample bottles of Polypropylen NALGENE, 30 ml

7 Chemicals

Ultra pure water (RW) for cleaning the PP sample tubes, for dilutions, washing the devices and for production of KBL

HNO3 65% ultra pure identification: C - caustique, R 35,

prefabricated calibration intial solutions KSL_... for elements As, Al, Fe, Cr, Ni, Cu, Zn, Cd, Pb, Pt, Rh, Ti, V, Se and Sb:

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These will be compiled from individual and mix standards (SL) see belonging documentation

prefabricated ISS for elements Sc, Y, Tb and Ir (also produced from SL)

prefabricated ISA for elements Sc, Y, Tb and Ir (produced from ISS)

Quality control solution (QK), produced from standard reference material NIST-SRM 1633a - Trace Elements in Coal Fly Ash.

8 Processing

8.1 Sample handling

8.1.1 Dust filter (STLV)

Sampling and transport and transfer of filter in petri bowls is made using air measuring

network. After the gravimetric determination of dust, the filters will be taken in

department 500 and will be put to microwave disintegration.

After disintegration are appearing the analyzing trace metals in dissolved form (ions) in

sample bottles of polyproylen.

8.1.2 Dust deposit (STND)

Sampling and transport and the transferr of the dust deposits in the vaporisation bowls are

done by means of air measurement network. After a gravimetric determination of the dust

deposit, the vaporization bowls will be carried over and the microwave disintegration is

taken place.

After disintegration are produced the analyzed trace metals in dissolved form (ions) in

sample bottles of polypropylen.

8.2 Calibration

Before the measurement at the ICP-MS is taken place, a calibration must be carried out

(see SOP ICPMS―, no. 6.5).

The calibration linear is establishing the estimated measurement field using multi element

or individual element standards for every element

8.2.1 Basic calibration

Basic calibration is made basically with a KBL and min. 5 equidistant concentrations of

the calibration standards (STD......) in the working field. This is necessary only

- in the practicing phase

- after substantial modifications in the measurement conditions

- at least 1x year (documentation)

8.2.2 Routine calibration

For the daily routine a calibration will be carried out with 1 KBL plus 3 calibration

standard (STD......).

These 3 calibration standards have to form a partially quantity from the standards of the

basic calibration, if necessary.

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Each measurement point represents the average value of the three replicate

measurements.

Determination factor R2 must be > 0,9990. Otherwise, the calibration has to be repetead.

8.2.3 Ten point-calibration

Ten point-calibration is for the determination of the device parameters. It is need for the validation of the procedure. 10 calibration standards (ZPK......) with equidistant distances will be established, whose concentration is placed close to the presumed/previous detection limit of the device for the analyzed isotope. Calibration is carrying out. Accepted calibration curve will be evaluated according to DIN 32645 using program „DIN-Test―.

8.3 Measurement and evaluation

8.3.1 Measurement

Condition of the device and steering software are

a) in the device -SOP SOP „ICPMS― cap. 6 and

b) in „user manual of the VARIAN ICP-MS 820―

is described in detail.

Because this is often used, here will be given an overview of the general step

arrangement.

- Check the calibration using repeated measurements of a calibration standard (STD...3)

- Sample input;

First sample is always KBL, followed each by a QK and at least a control sample (as

possible STD...3), where all the 10 samples have to be cyclic measured.

- Sampler assembly.

- Analyze start.

- Samples whose measure results are above the calibration field (flag at measure value:

„x―), have to be diluted and again measured. At the repetitive measurements are only

the elements to be evaluated whose results are in undiluted state above the calibration

field.

- Data assurance.

8.3.2 Evaluation

Data will be saved in the list „..“ in the respective subdirectory according to the year and

the sample matrix (STLV or STND).

- Because for an element often more isotopes has been measured, a respective method for

an isotope will be selected or the average value of the isotope will be formed.

- If there is systematic displacement of the calibration, than it can be calculated a correction

factor of all 10 samples of co-measured STD... Factor will be formed from all the

concentrations of the investigated control standards (STD...3) and the target value. For

each control standard, a factor will be determined and decides, on which sample what

factor should be used.

Factor = Target value : Current value

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- Only formed averaged values will be further on evaluated and with the factor corrected.

8.4 Disposal

Analyze residues will be collected collecting containers additional to the ICP-MS. If this is

full, than it can be transferred to the waste water through the laboratory waste water

(neutralization of acids), as far as no higher contents of pollutants will be analyzed. These

high polluted samples are collected separate as hazardous waste and are professional

eliminated.

8.5 Declaration and storage of results

Results (Original-primal values, according to EXCEL exported primal values and evaluated

and transferred values) are saved in folders beginning with 2007 related to years.

9 Quality assurance

Quality assurance is assured by carrying along for each STD and at least a QK. For

each intern standard it will be supervised at least one isotope, so that the mass field

will be covered approx. even.

For the begin of a routine course it must be analyzed at least one time one QK, that

came up from the SRM and has been disintegrated together with the samples. Based

on the analyze results, the recovery rate will be calculated every half-a-year.

At least 10 samples will be measured for each calibration in a control sample

(STD...3).

Software verifies during the measurement of the STD...3 for these selected isotope, if

the device works without errors.

For deviations of more than 10% must result a recalibration (automatic).

At some elements will be more isotope for testing measured, from witch (by the user

after measurement) an average value (for ex. Zn) or (during the measurement of the

device software) a sum (for. ex. Pb) will be formed.

To analyze there will be done a three time determination for each solution. it will be

made automatic an average value of the values of the determination. This must be

checked on the RSD.

Periodically it will be made a procedure blank value (procedure BW) and co-

measured (disintegration of the used chemicals).

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The following check cards will be established (as multi-element control cards):

Control medium KK-Art controled Isotope Name

Labor-BW Blank value-KK

for STLV

Ni60, As75, Cd112,

∑Pb206/207/208 in STLV-

Samples

ICP-MS_Labor-BW_S

field-BW Blank value-KK

for STLV

Ni60, As75, Cd112,

∑Pb206/207/208

in STLV-Samples

ICP-MS_Field-BW_S

Verfahrens-BW Blank value-KK

for STLV

Ni60, As75, Cd112,

∑Pb206/207/208

in STLV-Samples

ICP-MS_Verfahrens-BW_S

Field-BW Blank value-KK

for STND

Ni60, As75, Cd112,

∑Pb206/207/208

in STND-Samples

ICP-MS_Field-BW_N

Zert. Referencemat.

(NIST 1633a)

Target value-KK

for STLV

Ni60, As75, Cd112,

∑Pb206/207/208

in STLV-Samples

ICP-MS_1633a_20-ZW

Zert. Referenzmat.

(NIST 1633a)

Target value-KK

for STND

Ni60, As75, Cd112,

∑Pb206/207/208

in STND-Samples

ICP-MS_1633a_50-ZW

Calibration -STD 3 Target value-KK

in STLV- und

STND-Samples

Ni60, As75, Cd112,

∑Pb206/207/208

in STLV-Samples

ICP-MS_STD3-ZW_S

10 Belonging documentation

User manual of VARIAN ICP-MS 820

HPLC-System Merck

Content

1 Definition ............................................................................................................... 306

2 Area of application ................................................................................................. 306

3 Scope ..................................................................................................................... 306

4 Terms / Abbreviations ............................................................................................ 306

5 Responsabilities ..................................................................................................... 306

6 Description ............................................................................................................. 306 6.1 Configuration of system ......................................................................................... 306

6.2 Software activation ................................................................................................. 307

6.3 System start ............................................................................................................ 307

6.4 Developing of a sequent for a chromatogram capture ........................................... 307

6.5 Sequenz – after processing ..................................................................................... 308

6.6 Sequenz - Start ....................................................................................................... 308

6.7 Shut down the system ............................................................................................. 308 6.7.1 Stopp analysing ...................................................................................................................... 308

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6.7.2 Shutting down the installation ................................................................................................ 309

6.8 System maintenance ............................................................................................... 309

7 Applied documentation .......................................................................................... 309

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9 Definition

Program controlled chromatography with high-pressure liquid for analyzing the polycyclic

aromatically hydrocarbons

10 Area of application

This SOP is applied for HPLC-System of the producer Hitachi High-Technologies

Corporation

11 Scope

This SOP regulates the procedure for handling, function control and maintenance of the

HPLC-Systems [ LaChrom Elite ]

12 Terms / Abbreviations

DL Head of department

GV Instrument- responsible

AL Head of bureau

13 Responsabilities

Activity Responsable Co-action Information

Configuration of systems GV DL

Switch on and off the system user

Another maintenance and

service operations as agreed

with the technical service

GV user DL

Approval or stopping the instruments GV DL

Elaborating the chromatography methods user GV

Implementing of the methods user

Control and change the spare parts GV user

14 Description

The system consists of pump L-2130 with an integrated solvent degasser, auto- sampler L-

2200, Diodenarray – Detector L-2450, fluorescent – detector L-2480, column – thermostat

with an separation column UltraSep ES PAH B. 507/00 ; Col. 250x2 mm incl. precolumn

cartridge from Sepserv and computer from Dell Optiplex GX 260 with HP Deskjet 3550

printer.

14.1 Configuration of system

A modification of the configuration can only be done by a GV or client service.

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14.2 Software activation

To access the steering software it‘s only possible by using the user notification through the

EZChromElite – connection and activating the HPLC-2 – Symbols on the desktop.

14.3 System start

All the system components have to be turned on before activating the steering software. The

next added instrument after Software-Start, Wizard HPLC -2 window has to be closed.

From the menu bar, the Control → Instrument Status → Pump, the ― Turn ON ― – command

is to be activated and ― Manual Set ― and flow rate 0,4 ml/min should be recorded.

Under ―Purge ― the following commands to ―Purging―should be accomplished. In this

context opening the release valve before flushing the pumps and closing on command ―Stop

Purging―is important.

The flow rate and the system pressure [250 – 290 bar] can be controlled in the record card→

System.

Subsequent, using record card → Sampler ―Wash Pump Plunger ―position will be accessed

and the under menu will be worked off. Air bubble will be aspirated with a plastic injection

when the piston of the sampler top is running up of. These steps should be repeated up to

release the air blister of the injection piston chamber. Any time under Control→ Instrument

Status a sequent system control can be done.

14.4 Developing of a sequent for a chromatogram capture

The EZChrom Elite user manual covers a detailed instruction. Further on the help-function

can be access on any levels. The usual way of proceeding is as follows:

From the symbol bar access the wizard instrument.

Create a sequence :

Method : current method \ Fl_optimum_10_a_scharp_A.met

Data File Type: For acquisition

Amount values: all on ―1 ― next >

Sample ID : no input

Data path : Data\ * current year \ * folder for data

*these folders will be created with explorer under D:\EZChrom

Elite\Enterprise\Projects\PAH\Data off the wizard

Data file : Sample ID ( <ID>)

Unknown runs : number of samples

Repetitions : 1 next >

Unknown vials : each on ―1 ―

Calibration vials : each on ―1 ―

Auto-sampler : 10 µl next >

Calibration ID : ― no input ―

Calibration path : identical with data path

Calibration file : with the software automatically registred

Number of calibration levels : standard number

Repetitions per level : 1

√ Clear all calibration at start of sequence next >

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No other input necessary.

→ Finalize respectively back for correction

14.5 Sequenz – after processing

The developed sequent must be modified:

1. Insert on start row → Run # → Nr.1 [ left/right mouse button ]

2. Copy of ― Run Type – Unknown ― - Row in row 1

3. Column ― Conc Override ― checking for all standards [left mouse button on the blue

triangle ; both detectors - FL / 1:291nm;4nm – correct if necessary]

4. Column ― Vial ― : continues testing assembly

5. Sample ID : place 1 → ACN – 1

place 2 and continuously → Standard-concentration and samples

samples

z.B. : Vial

1 ACN-1

2 to 7 St. 2ppb to 100 ppb

8 and continuously LHST 15

6. Column ―Method ― : activate the field underneath the last sample with the left mouse

button and open method ―flow stop.met ―

7. Filename: choose identical name before ―.dat ― with sample ID; use no forbidden data

signs [ -;/.]

8. fading out unneeded columns of the sequent table with the right mouse button → ―

Properties ―

9. fading out needed columns of the sequent table with the right mouse button →

― Properties ―

in the row of the flow Stop . met in ―Run Typ ―- column, click on the blue triangle, and

then select ―Shutdown― – Run Type and activate with ―OK―

10. sequent saving under → File\Sequence\Save as

Note: already filed sequent can be used as origin for the new operations. Then data path can

not be defined [input in old folders].

14.6 Sequenz - Start

Activate double green arrow from the symbol bar [ Run Sequence ].

Sequence name: current name

Run range: ― All ―

Printing : no activating

Bracketing : ― None ―

Review : no activating

→ Start

14.7 Shut down the system

14.7.1 Stopp analysing

On menu bar → Stop run

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- depending on problem kind → Stop the current recording or → Stop the entire sequent

14.7.2 Shutting down the installation

―Instrument Activity Log ― with the input ― Run Queue – Complete Sequence Run― shows

up on the desktop after a successful finalization of the sequent―.

The windows of the steering software will be closed.

HPLC – System will be disconnected from the network.

6.8 System maintenance

According to 6.3, longer service life has to be over bridged by starting the systems. In this

phase, the installation needs to establish a pressure from 240 to 290. If this field is not

adjusted after few minutes, then every component has to be verified [leakage, obstruction,

conduction problems].

Detailed specifications about the way of proceeding contain the instrument documentation.

15 Applied documentation

Producer‘s instructions of the for the system components

Determination of polycyclic aromatic hydrocarbons in particulate matter

Content

1 Definition of procedure .......................................................................................... 311

2 Appliance field of procedure ................................................................................... 311

3 Scope of this procedure .......................................................................................... 311

4 Basic principles of the procedure ............................................................................ 311

5 Reference to the valid standards ............................................................................ 311

6 Devices (and auxiliary materials) ............................................................................ 311

7 Chemicals ............................................................................................................... 312 7.1 List of the necessary chemicals .............................................................................. 312

8 Process ................................................................................................................... 312 8.1 Sampling ................................................................................................................. 312

8.2 Sample preapering .................................................................................................. 313

8.3 Calibration .............................................................................................................. 313

8.4 Measurement and evaluation .................................................................................. 313

8.5 Disposal .................................................................................................................. 314

8.6 Presentation and storage of the results ................................................................... 314

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9 Quality assurance ................................................................................................... 314

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11 Definition of procedure

Determination of polycyclic aromatic hydrocarbons (PAH) in particulate matter with HPLC

after fluid-solid-extraction.

12 Appliance field of procedure

The procedure is used for determination of the particulate matters related to PAH, collected in

filters from the ambient air within the air quality monitoring. Gaseous PAH can not be

determined. The procedure is used for the determination of PAH with 4 and more rings.

13 Scope of this procedure

Some polycyclic aromatic carbonate hydrates are classified as carcinogen substances. They

are appearing during uncompleted firing processes and adhere on the respirable particulate

matter and so they are determined as particulate matter components.

In the UE-Directive for air quality, Benzo(a)pyren (main component for PAH) is described as

substance that has to be supervised.

Following PAH have to be quantified:

Compounds Abbreviation

Pyren PYR

Benzo(a)anthracen BaA

Chrysen CHR

Benzo(e)pyren BeP

Benzo(b)fluoranthen BbF

Benzo(k)fluoranthen BkF

Benzo(a)pyren BaP

Dibenzo(a,h)anthracen DahA

Benzo(g,h,i)perylen BghiP

Indeno(1,2,3-cd)pyren INP

Coronen COR

14 Basic principles of the procedure

The polycyclic aromatic carbonate hydrates related to the particles will be extracted using

toluene in the ultra sonic bath and determined after several steps of preparing the sample

using HPLC together with FLD and DAD.

15 Reference to the valid standards

DIN ISO 16326:

Ambient air-

Determination of the polycyclic aromatic carbonate hydrates with the high performance liquid

chromatography

16 Devices (and auxiliary materials)

- Ultra sonic bath: Sonorex, RK 1028, von Bandelin

- Rotation vaporizer: R-124 von Büchi

with Vacobox: B-171 and water bath B-480

- fridge in the room 3.204 and 3.303

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- glass cups

- Alu-Round plates (diameter: 100 mm, thickness: 0,03 mm)

- Injection flask with glass stopper (10 ml)

- Analyze scale with clearness of display of 0,01 mg

- injection preliminary filter: GHP, Acrodisc Minispike 13 mm, 0,45 µm

- injection with Luer connection, standard Ject, volume 1 ml

- installation HPLC (Merck-Hitachi) (devices SOP: 6-G-HPLC1)::

- sample bottles: brown glass, 1,5 ml, with screw seal and cut septen, blue-white (special for

Merck-Hitachi HPLC)

- Dispenser support 10 ml (Dispensette Organic, Easy Calibration von Brand)

Pipette:

- Measure pipette

- Air-cushion pipette (v. Eppendorf)

- Direct displaced pipett (Transferpettor v. Brand)

Verified pipettes will be used for working steps that are relevant for the quality for ex. using

control and calibration standards, establishing of sampler dilution etc.

17 Chemicals

17.1 List of the necessary chemicals

Toluene for HPLC, for ex. Riedel de Haën Art.Nr. 34866

Acetonitrile for HPLC, Ultra Gradient Grade, for ex. Baker Art.Nr. 9017

Water for HPLC (ultra pure water from room: 3.211)

Calibration standards dissolved in Acetonitrile:

concentration 10 ng/µl

PAH-Mix 9: 16 PAK after EPA (v. Dr. Ehrenstorfer)

Coronene (v. Dr. Ehrenstorfer)

Benzo(e)pyrene (v. Dr. Ehrenstorfer)

Cyclopenta(c,d)pyrene (v. Dr. Ehrenstorfer)

Indeno(1,2,3-c,d)flouranthene (Interner Standard)

Control standard dissolved in Acetonitrile:

PAH-Calibration-Mix, Art.Nr. U-JTB-0005 (v. Promochem)

Reference material:

NIST-Reference material SRM 1649a

18 Process

18.1 Sampling

Sampling, transport and transfer of filter in the Petri bowls and gravimetric determination of

the separated quantity are made using the air measurement network. Afterwards the samples

will be stored in the Petri bowls in the fridge at (8°C 2) until the sample are ready for the

preparation step. The samples of the month will be prepared together. All the containers will

be labeled with the name of the sample. For a better identification of the sampling place can

be used different colored pen.

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18.2 Sample preapering

For the liquid extraction, the filter (clogged filter and blank value filter) is transferred in the

150 ml glass cup. As inter standard10 µl Indeno(1,2,3-c,d) fluoranthen will be added with a

Pipette (Transferpipette, Nr. 02T0330). Afterwards results the addition of 10 ml Toluene

(from the reserve bottle with a dispenser support) to the filter. The glass cup will be covered

with an aluminum round cap and will be put in the ultra sonic bath. The ultra sonic extraction

takes 30 minutes. Afterwards 8 ml des Toluene-Extract will be transferred in an 10 ml

injection plunger using glass pipette (measure pipette 10 ml) and put into an rotation

vaporizer until it is dry. Here attention will be paid so that the sample immediately from the

rotation vaporizer will be removed. The residue will be dissolved in 2 ml toluene. The

injection plunger will be kept in the ultra sonic bath for about 1 minute after adding toluene.

The sample will be kept over the night in the fridge in the locked injection plunger. Toluene

will be rotated until has dried and the residue will be dissolved in 1 ml acetonitrile. Afterward

the sample solution will be transferred through an injection pre-filter (GHP, Acrodisc) in the

sample container of the sampler givers. Samples and quality assurance samples will be stored

in the fridge up to the analyze step.

18.3 Calibration

The production of the calibration standard is described in an short instruction (co-valid

documentation).

Due to the nonlinearity of the fluorescent detector at higher concentrations (for ex. for BaP,

maximal concentration 100 ng/ml) the measurement field has an upper limit.

Calibration field of FLD: 2 ng/ml to 100 ng/ml

Calibration field for DAD: 10 ng/ml to 100 ng/ml

18.4 Measurement and evaluation

The device command and the capture of the chromatogram using chromatographic software

are described in the device SOP. For each sample series are calibration standards to be

established. To obtain reproducible retention times, an injection of pure acetonitrile will be

carried out before the injection of the first sample (the lowest calibration standard). For

quality assurance, three control samples (samples PAH-control standard; U-JTB-0005) will be

analyzed in the sequence. After a successful completion of the sample sequence, the raw data

folders are in the established folders ready for evaluation. A detailed list of the software

possibilities for chromatogram process is in the user manual to be found. Basically, the next

step order will be respected:

Load the current method

File→Method→Open→ FL_Optimum_10_a_scharp_A.met

Opent the raw data-file

File→Data→Open

– the structured image is multiple and it will be graded for detector selection

Load the reference chromatogram

Right mouse buttons →Add Trace→Data source→Open Data→Kalibrier-Datei [z.B.

100ppb.dat]→Trace [FL oder 291nm,4 nm]→OK

Control the name of the Peak and Peak-Integration

Method→Peaks/Groups

In the symbol bar ↓ both detectors [FL or 291nm,4 nm] can be activated. The card ―Named

Peaks‖ consist all substances with retention times. Deviations in the peak nominalization and

integration error can be correct using the lower symbol bar. These symbols are self-

explanatory. All the modifications are accepted by the software only after ―Insert into Manual

Integration Fixestable‖ and ―Analyze Now‖-command. If the carried handlings don‘t have the

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desired effect, under Data→Manual Integration Fixes, by deactivating the command and post-

analyze [Analyze-Symbol] the initial state can be reactivated.

Chromatogram of used standards can be corrected on the same way. Under symbol ―Review

Peak Calibration ‖ the calibration function is available for both detectors and every substance.

If the detailed post-integration can not be used on the calibration linear, than on the menu bar

after the next model under Sequence→Process is a reintegration to be carried out.

– Name of the current sequence

– Range

– Processing mode as Reintegrate

– Bracketing None

Finishing the result journal

• Open the Custom Report under Method on the menu bar

• Detector selection under File→Report Template→open

DAD Graph AE scharp.rep

FL Graph AE scharp.srp

• Chromatogram window with Double click left MT under Axis Setup if

necessary

• Update calibration window with Double click left MT under Peak if necessary

• print journal under Reports→View→Method Custom Report using

right MT

18.5 Disposal

Organical solvents (Toluene, Acetonitrile resp. Acetonitrile water mix and sample

residues) will be collected in an adequate labeled can. Waste removal is periodically

taken place by an authorized firm.

18.6 Presentation and storage of the results

Analyze results (raw data) will be recorded in the prepared Excel-tables (belonging

documentation), where calculations of the end results will be carried out. Data will be

periodically saved on server and stored. Chromatogram will be printed and order after

measurement years (archive time is at least 5 years).

19 Quality assurance

Quality assurance take place by preparing the filter, reference material and determination of

the field and laboratory blank values at the sample series. For every sample determination will

be analyzed two control sample (U-JTB-0005) Filter, two Reference material samples (NIST-

Standard), at least one empty filter (Laboratory blank values) and a container empty filter

(field blank values) according to the specifications of the air measurement network. During

analyzing of sample series, the control sample form the control stand will be measured (U-

JTB-0005). For qualifying the retention times in the chromatogram of the DAD an interne

standard will be added (Indeno(1,2,3-c,d)fluoranthen).

For analyzing BaP, BkF, BbF, INP next control cards has to be ticked:

- Average value target card of the control sample (U-JTB-0005)

- Range target card of samples and reference material (NIST-SRM 1649a)

- Finding Target card (extent Filter)

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Ionenchromatograph-Metrohm

Content

1 Definition 316

2 Application area 316

3 Scope 316

4 Terms / Abbreviations 316

5 Responsibilities 316

6 Description 317 6.1 Production of eluent and suppressor solution 317

6.1.1 Production of the Anion eluent and suppressor solution 317

6.1.2 Production of the cation eluent 317

6.2 Moving needle 788 318

6.3 Starting the system 318

6.4 Measurement 319

6.5 Evaluation of the chromatograms 322

6.6 Shutting down the instalation 322

7 Documentation 323

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16 Definition

Determining of multi-cation and anions by means of ion chromatography

17 Application area

This SOP applies for the IC-System which is in use and comes from the producer Methrom

for determining the anion and cation in the air quality samplers.

18 Scope

This SOP regulates the handling procedure, function control and maintenance of the ion

chromatography system.

19 Terms / Abbreviations

IC Ion chromatograph

DL Steering bureau

GV Instrument responsible

PL Testing supervising (for all routing analysis of the instrument)

QMV quality management responsible

AL head of department

20 Responsibilities

Activity Responsible Co-activity Information

Configuration of the system

GV DL

Switch on and off the system

GV user

Routing maintenance of the system

GV user PL

Another maintenance and service operations agreed by the technical service

GV user DL

Instrument approval or blocking GV DL QMV, Al

Establishing the measurement and evaluation methods

PL GV, user

Preparation and operation of sequent

GV PL/user

Re-processing and GV PL/user

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Activity Responsible Co-activity Information

evaluation

21 Description

The modular built system consists of components presented in the instrument documentation.

The system allows the operation with two separation columns and the utilization of the

suppressor technique by the determination of the anions. All the modules can be operated with

the software (IC-Net).

21.1 Production of eluent and suppressor solution

For the determination with the separation column Metrosep A SUPP 5 it will be used a

sodium carbonate –hydrogen carbonat Eluent. For the regeneration of the suppressors it will

be used an 0,05 molar sulfuric acid.

For cation column Metrosep C2 150/4.0 it should be used a tartaric acid / dipicolin acid -

solution.

21.1.1 Production of the Anion eluent and suppressor solution

For the anion eluent will be produced 1 molar parent solution:

→ 1mol/l Na2CO3: 10,6 g Na2CO3, for explanation weighing and filling ultra pure water to

100 ml in an 100 ml volumetric flask

→ 1mol/l NaHCO3: 8,4 g NaHCO3, for explanation weighing and filling ultra pure water to

100 ml in an 100 ml volumetric flask

The parent solutions provided with the production data will be stored in the fridge.

Labeling (parent solutions): no hazardous substance symbol.

Eluent should always be used fresh from the parent solutions. Here 3,2 ml Na2CO3 parent

solution (1 mol/l) and 1,0 ml NaHCO3 parent solution (1 mol/l) will be transferred in 1 liter

plastic volumetric flask and filled with ultra pure water up to 1 liter. The added volume of the

eluent will be double for one 2-liter eluent quantity. The eluent will be filtered through a

vacuum filter (Cellulose acetate Filter, 0,45 µm) and degassed and after that it will be filled in

a stock container with adequate labeling.

Labeling (Eluent Anion): no hazardous substance symbol

For the suppressor it should be an 0,05 mol/L H2SO4 produced. For this an ampoule of

titrisol-solution (0,05 mol/l H2SO4) should be filled up one liter in an volumetric flask.

Labeling (H2SO4 50 mol/l): no hazardous substance symbol

Both solutions will be transferred in the adequate labeled container of the ion-chromatograph

device.

Ultra pure water will be find in an third stock container (conductibility: 18,3 mΩ), which will

be refilled after each analyze.

21.1.2 Production of the cation eluent

Production of the eluent concentrate:

Net weight: 6 g tartaric acid (f.e)

1,67 g Dipicolin acid f.e. (Pyridin-2,6-dicarbonic acid)

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Both weights will be given into a 1liter Erlenmeyer flask, heated at 50°C and agitated in 800

ml. After cooling down and transferring into an 1 liter plastic volumetric flask, the ultra pure

water will be filled up to a measuring mark.

Labeling (Eluent concentrate cation): no hazardous substance symbol

Production of Eluent from the concentrate through dilution of 100 ml concentrates to 1 liter

in a 1 liter plastic volumetric flask. The added volume of the eluent will be doubled for a 2

liter eluent quantity. The eluent will be filtered through a vacuum filter (cellulose acetate-

filter, 0,45µm), degassed and filled into a adequate labeled stock container.

Eluent comprises 4,0 mmol/l tartaric acid and 1,0 mmol/l Dipicolin acid.

Labeling (Eluent cation): no hazardous substance symbol.

Production of 1 molar nitric acid:

Handling of nitric acid production to acidify the sample for the determination of cation:

1 ml nitric acid p.A. (65%) and 9 ml ultra pure water (MembraPur)

21.2 Moving needle 788

In the moving needle 788 is a filtration unit integrated. In this way is the filtration of the

sampler not applicable anymore. The moving needle has to be regularly controlled on

dirt in the tubes and if necessary cleared with a washing agent of sodium hypochlorite

solution (see production of sodium hypochlorite solution). The filtration membrane

(Cellulose acetate filter, 0,15 µm) will be also regularly controlled and changed if

necessary (see manual). The samplers are filled in the 10 ml sampler vials and closed

with proper caps. Attention will be paid so that the interior surface of the cap will not

come in contact with the hands (contamination danger). The containers for the

washing agents will be filled before the analyze with ultra pure water (indication: 18,3

mΩ) begins.

Production of sodium hypochlorite solution (1,3 % active chlorine):

25 ml sodium hypochlorite solution 13 %, technical to 250 ml ultra pure water

Solution contains 1,3 % active chlorine

Identification (sodium hypochlorite solution): no hazardous substance symbol

21.3 Starting the system

Turn on the modules of the ion chromatography-device and of the UV/VIS-detectors

Attention: Turn on the Interface only after starting the PC

Starting the computer and the monitor

Printer doesn‘t need to be switched on, because it is in the standby modus (energy economy

modus) and it doesn‘t get switched off.

Notification on PC without password:

Strg + Alt +Entf

„no password entry― ok

Open the IC-Net 2.3 with double click on the desktop symbol

Notification:

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User Name: ic

Password: ic

Confirmation with Login Switch on the Interface

Start the steering and evaluation software

Open the IC-System by clicking the Mod-Symbol on the symbol bar

There are 4 Systems (2 for Anion and 2 for cation) recorded

The last utilized system is appearing. If alternation is needed, than click on

[System ] [open other] and the required system.

Anion systems:

Anions 788 (Anion system with moving needle 788 and filtration unit)

Cation systems:

Cation 788 (cation systems with moving needle 788, filtration unit)

Observation:

The routine analyze with enough sampler quantity will be carried out with the moving needle

788. This moving needle will be completely steered by the software.

Attention:

If the moving needle should be changed, the capillary of the inlet valve has to be connected at

the moving needle (in the ion chromatography device)

21.4 Measurement

By opening the systems (for ex. anion788.smt or cation 788.smt), the respective pumps will

start. Since during the anion determination the effluent is flowing on the suppressor column,

tube pump starts for the transportation of regeneration solution. By clicking on each module

the checking of each module is carried out via monitor.

Anion pump:

Flow of the anion pump: 0,7 ml/min

Pressure notification: 11,4 - 13

Cation pump:

Flow of the cation pump: 1 ml/min

Pressure notification: 6,4 - 10

As the system is provided only with a conductibility detector, after flowing through the

separation column over the control valve Valve A at the Eluent-Organizer, the Eluent flows

either to detector or to garbage container.

Valve position (valve A):

on Inject for the Anion eluent to the detector

on Fill for the cation eluent to the detector

After that, click on the subdirectory of [control] menu point [start up hardware] and observe

the basis line. Two detectors are in use at the anion determination (conductibility and UV/VIS

detectors). The basis lines will be presented on the desktop for both detectors. As soon the

basis line is steady, analyze can begin.

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After changing the system resp. eluent or the long holding time between the sampler series, a

standard solution will be injected for controlling the residence time and concentration. Here

are the next steps to be carried out:

Sampler injection

One sampler can be injected using the menu point [control] nd [start determination]. A table

will open here and the sampler names and sampler position will be recorded. The moving

needle has to be adequate charged. The containers for the washing agent will be fresh filled

with ultra pure water.

Observation:

The operation of turning the sample rack for filling up the washing agent must be carried out

before starting analyzing and it will be controlled by software. The moving needle will be

opened by double clicking the module in the system window and selecting in the new window

[manual]. After that, the sampler position will be registered on the sampler rack

[move][Position]. Sample rack turns around until reaches the given position.

The name of the sample (de ex. KSTD Level x), injection volume (20 µl) and the sample

position in the moving needle (788) will be filled in the sample window.

Analyze will start by clicking the [start] Symbol.

The white provided diagram will turn into blue after injection.

After analyzing end, there will be a check of the analyze retention time and of the estimated

concentrations.

If the retention time had suffered a modification by exceeding the tolerance boundaries, the

peaks can not be assigned by the system and the peak will be numbered. The numbered peak

of the component must be reassigned. (s. 6.5).

Establishing a sample table (Sample queue) Open the [System] in the system window and click on [sample queue]. Fill in the name of the

sample table and [open] the sample table for inserting the samples.

If the installation should stop after analyze proceeding, then it should be activated the box

shut down system in the sample table.

In the first column is the current number.

In the second column is the system. In both columns modifications are needed.

Following inputs have to be carried out:

Ident: Sample definition

Vial: Sample number in Probengeber 788

Volume: 20 µl

Dilution: Dilution

Amount: 1

Internal Standard Amount: 100

Level: Calibration level (0 is for sample, 1,2,3.... for the level of the calibration

solutions

Injections: Number of injections

Done: No input (0 before injection, 1 after analysis)

Sample Info 1 and 2: samples information entries (for ex. not acidified)

Through the symbols on the menu bar, rows can be copied and provided with a current

number. As routine, the sample tables have the following structure:

Ident Sample Info 1 Sample Blank value

Water

Membra pure Water Blank value

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Standard Xx STD Level x Standard calibration of a level as sample

Control sample KP xxx Control sample for MW-control card

sample 1 sample sample

sample 2

sample 3 For ex. field blank

value

........

sample 10

Standard

samples ff.

.........

Standard

Blank value

Field blank values and laboratory blank values will be handled as samples. The identification

depends on the sample origin and the type of sample.

The following sample nomenclature will be applied:

[sample type] [site] [data]

Example:

[L] [Ro] [041029]

[L] for small filter (fine dust extrakt)

[Ro] for Rostock

[year/month/day]

Type of samples:

Abbreviation Sample

L Fine dust extract (small filter resp. Leckel filter)

R Rain sample (rain collector)

B Bergerhoff sample (total precipitation)

BW Blank value

KP Control sample

C_BW Container blank value / field blank value

D Denuder samples

For special samples and extend of the sites, sample identification will be set through PL and inserted

in a device documentation.

After establishing, the sample table will be printed and the identification of the sample queue and

data will be written on the print. With the confirmation of the sample table (green tick mark), the

sample table will be saved and the analyze starts.

Calibration For the calibration of the system, the input will be instead of samples the calibration standards with

adequate levels. The calibration levels with the adequate concentrations have to be saved in the

methods for anion and cation. Because the calibration values don‘t get modified in the routine and

additionally, before the analyze starts, by means of the calibration standards, a new calibration will be

carried out through the entire working field (only if necessary for ex. if the calibration standard is

outside the stipulated tolerances (15%)).

Production of the calibration standards is described in a short instruction (s. belonging

documentation).

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21.5 Evaluation of the chromatograms

Chromatograms will be printed after analyze ending and controlled upon the proper classification of

the retention time and the correct peak integration. The chromatograms can be processes afterwards. Post-processing of the chromatograms:

1. List of the saved chromatogram by clicking the open-symbol of the symbol bar.

Note:

On the list, the chromatogram are classified after analyzing data. The last saved chromatogram

is on top of the list.

2. Open the method

click on [Method] on the menu bar

3. Peak clasification

[Method]

[Calibration]

[Components]

The numbered Peaks in Chromatogram will be classified to the peak names

(insert peak number in the first column (Peak), the retentions time is automatically

modifying)

after corrections, closing the component tables with ok.

4. Integration parameter

On the menu bar click on the integration symbol 0x :

The integration window opens. Integration parameter can be modified. The modification of the

integration parameters is especially for method development interesting. The integration

parameter can be modified.

5. Calibration levels

By opening the method subdirectory

[Calibration]

[Concentration]

opens the calibration windows. In this window, concentrations of the component standards can

be inserted for the respective level.

With add a concentration level can be inserted and can be cleared off with delete.

With ok the window is closing again and the inputs are taken over.

Method will be saved ([File] [Save] Method

21.6 Shutting down the instalation

After carrying out with success the sample table, the steering software is switched over in the modus

stand in the ion chromatograph (has to be written in the sample table s. 6.4). The UV/VIS detector will

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be switched manual, because it can not be steered by the software. The PC is shutting down by longer

time breaks. The modules will also shut down.

(The cation column will be extend in a multiple-week break and stored in eluent an in the fridge, see

column description).

22 Documentation

Operation instructions from Metrohm

Determination of anions and cations in the samples of ambient air

Content

1 Definition of procedure .......................................................................................... 324

2 Appliance area ....................................................................................................... 324

3 Scope of procedure ................................................................................................ 324

4 Basics of the procedure .......................................................................................... 324

5 Reference of valid norms ........................................................................................ 324

6 Devices .................................................................................................................. 324

7 Chemicals and auxilliary agents .............................................................................. 325 7.1 Chemicals ............................................................................................................... 325

7.2 Eluent ..................................................................................................................... 325

8 Process ................................................................................................................... 326 8.1 Sample handling ..................................................................................................... 326

8.2 Samples preparation ............................................................................................... 327 8.2.1 Rain samples ........................................................................................................................... 327

8.2.2 Dust deposit samples (Bergerhoff) ......................................................................................... 327

8.2.3 Particulate matter sample........................................................................................................ 327

8.2.4 Denuder samples .................................................................................................................... 327

8.3 Calibration .............................................................................................................. 328

8.4 Measuring and evaluating ...................................................................................... 328 8.4.1 Measuring ............................................................................................................................... 328

8.4.2 Evaluation ............................................................................................................................... 328

8.5 Declaration and storage of the result ...................................................................... 328

9 Quality assurance ................................................................................................... 328

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20 Definition of procedure

Determination of anion and cation using ion chromatography

21 Appliance area

Determination of chloride, nitrite, sulfur, phosphate, sodium, potassium, ammonia, calcium

and magnesium in the deposit sample and wet extract of particle matter resp. denuder.

22 Scope of procedure

Pollution of atmosphere with nitrate and sulfur compounds leads to nutrient penetration in the

natural ecosystems and affects the sensible balance. Determination of the nutrient input it‘s

done by analyzing the deposit and calculation of inputs through deposit quantity. Additionally

to the nutrients another ionic compounds are also determined (sodium and chloride), that are

also used for validation and source ordering of the analyze results.

In particulate matter, ionic participation are to be found not in a negligible order and will be

analyzed especially for ulterior source order of dust in water extracts.

Procedure is used also for determining the gaseous ammonia in the ambient air.

23 Basics of the procedure

Ion chromatography is one procedure for multiple element determination. It is an application

of the liquid chromatography with a conductibility detector with a additionally UV-detector

(only for nitrate and nitrite) and separation columns for anion and cation analyzers. It make

possible measurements in an concentration field of µg/L to mg/L.

24 Reference of valid norms

Measurement of rain compounds are in the VDI Directive to be found

VDI 3870, part 13: Determining of chloride, nitrate and sulfur in rain water using ion

chromatography with suppressor

DIN-Directives

DIN EN ISO 10304-1: Determination of dissolved anion fluoride, chloride, nitrite, Ortofosfat,

Bromid, Nitrate and Sulfate using Ion chromatography

DIN EN ISO 14911: Determination of dissolved cation Li, Na, NH4, K, Mn, Ca, Mg, Sr and

Ba using ion chromatography.

25 Devices

One module of the ion chromatography system from the firm Metrohm consists of 2 IC

pumps for separation columns, suppressor unit, interface, conductibility detector and UV

detector of the firm Sykam.

1 separation column for cation: Metrosep C2 150 with pre-column Metrosep C2 Guard

1 separation column for cation: Metrosep A SUPP 5 with pre-column RP Guard

1 sampler dispenser for smaller sample quantities (Metrohm, Modell: 698)

1 sampler dispenser with filtration unit (Metrohm, Modell: 788)

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The system excepting the UV-detector is controlled by the chromatography software IC-

Net 2.3. Device command and handling with the software is described in the devices SOP

(6-G-IC).

UV-Detector is set on a wave length of 215 nm and offers the extinction values via interface

an evaluating unit (PC).

Sartorius-Vacuum filtration unit and vacuum pump (on filtration and degassing of eluent)

Cellulose acetat filter, pore dimension: 0,45 µm, diameter: 50 mm

Cellulose acetat filter, pore dimension: 0,15 µm, diamter 50 mm

(Red point labeled) tested pipettes will be used at quality relevant working steps, like using

control and calibration standards, establishing the sample dilution etc.

Air cushion pipetts with variable volume setting:

Dosing volume: 1 to 10 ml (for dilution and transfer of samples in the sample vials)

Dosing volume: 100 - 1000 µl (dilution of the samples and standard production)

Dosing volume: 10 - 100 µl (dilution of the sample and standard production)

Direct pushing pipettes:

Transfer pipette, variable, volume 1 to 10 µl (acidifying the samples for the cation analyze)

Pipettes are listed in the data bank of the pipettes calibration program and will be tested after a

set calibration cycle.

Volumetric flask and beaker glasses of different dimensions of Polypropylen or Polyethylen

for the sample preparation and production of solutions. For solutions that will be put in 10 ml

volumetric flasks, there is no plastic material available. There will be used 10 ml glass

volumetric flasks. Solutions need to be transferred in a plastic container immediately after

their production.

Glass devices of different type.

26 Chemicals and auxilliary agents

26.1 Chemicals

Sodium hydrogen carbonat to analyze

sodium carbonate free from water to analyze

sulfuric acid (96 %) to analyze

sulfuric acid for 1000ml (Titrisol) c=0,05 Mol/L

(L+)-tartaric acid to analyze

Dipicolin acid (Pyridin-2,6-dicarbon acid)

Ultra pure water (LF < 0,1µS/cm)

Nitric acid to analyze 68%

Standard solutions of each analytic for the ion chromatography with a concentration in each

case of1000 mg/L.

Certified multid ion standard (concentration: 10,0 mg/kg)

Certified multi ion standard (concentration: 10,0 mg/kg)

26.2 Eluent

Sodium carbonate – hydrogen carbonate eluent will be used for anion determination with

separation columns Metrosep A SUPP 5. For the regeneration of the supressor it will be used

an 0,05 molar sulfur acid.

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For the cation column Metrosep C2 150/4.0 it will be used an tartaric acid/ dipicolin acid -

solution.

The production of solutions is described in the devices SOP IC.

27 Process

27.1 Sample handling

Samples will be collected by the department 500 and after a set up schema will be transferred

to department 630. The rain and Berghoff samples will be stored in collect containers and

kept in the fridge. The dust filter are in the scale room in Petri bowls and will be taken by

department 630 for sample treatment.

Rain samples will be as following identified:

R Gül 06 04

R = rain

Gül = sampling location

[06] = sampling year

[04] = sampling week

Dust deposit samples will be labeled as follows:

B Gül 06 04

B = Bergerhoff (dust deposit) Gül = sampling location

[06] = sampling year

[04] = sampling month

Particulate matter extracts will be labeled as follows:

L Gül 06 04 31

L = Leckel Filter Gül = sampling location

[06] = sampling year

[04] = sampling month

[31] = sampling day

Denuder extracts will be labeled as follows:

D 1 GÜL L 1 2908_260906 D = Denuder ([C_BW]=Container blank value, Lab_BW]=Laboratory blank

value

1 = Number of Denuder tubes (inapplicable at blank values)

GÜL = sampling location

L = Long tube (resp. K for short tube)

[1] = 1. measurement (double determination)

[2908_260906] = sampling calendar date

Sample vials will be also labeled additionally with A for anion and K for cation.

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27.2 Samples preparation

27.2.1 Rain samples

Rain quantity, pH value und conductibility will be determined from the rain samples after the

sample entry. The determination of the rain quantity takes place on analyzing scale with a

decomposition of 0,01 g. After transferring the rain samples in two 50 ml- sample tubes ( A

and B sample), that are labeled with the name of the sample, the conductibility will be

measured and than the ph value will be determined. For this some ml will be transferred from

the original sample in a small beaker glass. The measured conductibility and the determined

pH value will be recorded in the sample list, in which also the sampling period, rain quantity

and temperature are written down.

pH-value-sample will be made after the regulation so that the sample contamination with

KCl (from the Electrode) can be prevented.

At small rain quantity, pH value and conductibility can not be determined. In the sample

list will be a dash written down.

The samples will be frozen until the analyze step without any further sample preparation

steps.

27.2.2 Dust deposit samples (Bergerhoff)

Dust deposit samples will be scaled in sample containers (gross) and afterwards dissolved

for 15 min in ultra sonic bath and after a filtration using a analyze screen (0,355 mm)

transferred in a plastic beaker glass (1000 ml). If the volume is lower than 150 ml or no

liquid is in the Bergerhoff container, the sample will be filled with ultra pure water up to

150 ml. Volume will be registered on the sample list because it will be used for the input

calculations. Afterwards the sample will be transferred in the sample tube (50 ml) and

frozen as retain sample.

For the measurement will be filled one sample vail (10 ml) for each cation analytic and

anion analytic and frozen up to analyze. For the cation analytic will be inserted for 10 ml

sample volume 1m HNO3 sample container. For the anion determinations are no

chemical to provide.

27.2.3 Particulate matter sample

The filter clogged with particulate matter will be put in one 150 ml plastic beaker glass

and 20 ml ultra pure water (MembraPur) will be added to it. Beakers will be filled up

with ultra pure water before fluid/solid extraction begins and will be let it still for at least

2 hours. After that the beakers have to be emptied and dried. It is not allowed for beakers

to contain any adhered water drops.

The 10 minute-extraction takes place in an ultra sonic bath at the ambient temperature.

After that the watery extracts will be put to decantation and will be transferred in the

sample vials. Here is needed for the cation determination for 10 µl one 1 molar HNO3.

The samples will be frozen up to the analyze step.

27.2.4 Denuder samples

At latest one day after the sampling, the extraction of the covering of the denuder tubes

(samples, container and laboratories values) will be carried out. The extraction is made 3

times with ultra pure water, the extraction solution will bin in an 20 ml volumetric flask

transferred and filled up to the calibration mark. The eluat will be directly added each in

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2 sample vials (double determination), where 10 µl contain 1 molar HNO3 as sample,

and if it possible it will be immediately analyzed. If this is not possible, the samples will

be frozen up to analyze step. The working steps for occupying the denuder tubes and

extraction are described in a short instruction (see belonging documentation).

27.3 Calibration

The calibration solutions will be produced from individual substance standards having a

concentration of 1,000 g/Liter according to the instructions presented in the belonging

documentation. Calibration will be made after modification of the system for example

column change. For routine operations it is sufficient to control the system using control

standards in middle of the calibration field. Once in a year a complete calibration have to

be done over the entire measurement field.

27.4 Measuring and evaluating

27.4.1 Measuring

The tehnical preparations for measurements are described in a short instruction which is at the

working place to be found. Before analyze begins (sample table), the standard solutions and

the control samples will be verified for respecting the specifications (see chapter 9: quality

assurance). For meeting the specification the completion operation of the sample table should

start.

27.4.2 Evaluation

After completion of the sample table, the printed chromatogram will be evaluated. If the

analyze results are placed above the calibration field, adequate dilutions have to be don and

repeated measurements have to be carried out. For incorrect integration of the peaks and false

ordering to the analyte, the chromatogram has to be reprocessed. (see SOP IC).

27.5 Declaration and storage of the result

Analyze values in mg/l will be recorded in the adequate sample tables in excel file. The

calculation table are in the same excel file. The excel files are stored for he measurement year

declaring the sample type and sampling location at begin of the measurement year. Storage of

the results will be secure for the last 5 measurements years.

28 Quality assurance

Following quality assurance measures will be carried out.

Check the calibration before measurement begin using a calibration standard

(concentration: 1 mg/l) maxim allowable tolerance 15 %

Check the laboratories contamination using blank values measurements (pure water samples)

Use the targe value cards for each analyte: Multi element standards will be used as control sample in an concentration for each 1 mg/l (see list reference materials).

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Determination of dust precipitation as well as atmospheric deposition of heavy metals

Content

1 Definition ............................................................................................................... 330

2 Application area ..................................................................................................... 330

3 Scope ..................................................................................................................... 330

4 Terms / Abreviations .............................................................................................. 330

5 Responsabilities ..................................................................................................... 330

6 Description ............................................................................................................. 330 6.1 Measurement sites and investigation area .............................................................. 330

6.2 Handling with blank value samples for dust precipitation investigations .............. 331

6.3 Handling, storage si transferr of samples ............................................................... 331

6.4 Transferring of the maintenance plans, transferring journal and measurement results

331

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23 Definition

Determination of dust precipitation as well as of atmospheric deposition of heavy metals

24 Application area

Air monitoring network and air quality information systems

25 Scope

These SOP regulate the sampling for determination of dust precipitation quantity as well as

the atmospheric deposition of the heavy metals and ions.

26 Terms / Abreviations

27 Responsabilities

Activity Responsabiltiy Co-effect Information

Sampling

Sample preparation and transferring to the laboratory

Determination of the dust precipitation quantity

Quantity determination of the ions and dust precipitation

Quantitty

determination of the

heavy metals in dust

precipitation

28 Description

28.1 Measurement sites and investigation area

T he total deposition shall be investigated with dust precipitation collectors on a total of XXX

measurement sites. The collect time for the dust precipitation collectors is one month. Usually

it will be changed in the first day of the month.

The defined moments can be taken out of the maintenance plan. At the measurement

containers X1 and X2 the dust precipitation shall be determined using the following

determination of the heavy metals Pb, Cd, Cu, Cr, Ni, As (supl. 1 blank value determination

in X1). After the determination of the dust precipitation quantity, the samples will be sent to

the laboratory in marked vaporization bowls to analyze the heavy metal. On the sites …. Dust

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precipitation and water soluble ions Na +, K

+, Ca

2+, Mg

2+, NH4

+, NO3

-, Cl

-, SO4

2 - have to be

determined (supplementary a blank value determination in….). To obtain sufficient sample

quantity for analyze, double sampling will be carried out at the named stations. A container

will be needed for the determination of the dust precipitation quantity. The second sample

container serves for sample collecting for the ion analysis.

Tab. 1: Sites for dust precipitation measurements and analysis dimension

Stationsnr.

Station / Comp.

X1 X2. X3 .. .. .. ..

Number of placed

containers 2 2 1 3 2 2 2

Determination of

dust precipitation

quantity X X X X X X X

Determination of

heavy metals in dust

precipitation X X

Blank value for

heavy metals in dust

precipitation X

Determination of

ions in dust

precipitation X X X X X X

Blank value for ions

in dust precipitation X

28.2 Handling with blank value samples for dust precipitation investigations

In X1 will be placed a closed collector filled with 200 ml double distilled water. From

the 200 ml water, 50 ml will be got out by pipette and given to the laboratory for the

determination the blank value for the ions analytic. The rest of the liquid will be

vaporized in a vaporization bowl and given to the laboratory for the determination of

heavy metal blank value.

28.3 Handling, storage si transferr of samples

Sampling containers for ion-analyze will be totally marked and transferred without any

treatment to the laboratory. The three dust precipitation samples pro month for the heavy

metals analytic (X1, X2 and X1_blind) will be stored in a vaporized form in the glass

cabinet of the scaling space.

28.4 Transferring of the maintenance plans, transferring journal and measurement results

Necessary transferring journals will be given to the laboratory for every charge both in paper

form and in electronically form. The transferring journal contains information about

identification of the dust precipitation samples, collecting time and calculated dust

precipitation quantity. Data and samples are available for the laboratories one week after the

receiving the samples. Monthly maintenance planes will be put stored intern for begin of the

months for the laboratories, so that those can be seen. The results of the investigations on the

content in dust precipitation will be given away by the laboratories until May next year in

electronically form (excel file). Result files will be stored in the house network.

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Determination of the dust deposit in the ambient air

Content

1 Definition of procedure .......................................................................................... 333

2 Application area of the procedure .......................................................................... 333

3 Scope of the procedure .......................................................................................... 333

4 Basic principals of the procedure ............................................................................ 333

5 Reference to valid standards .................................................................................. 333

6 Devices................................................................................................................... 333

7 Chemichals and auxiliary material .......................................................................... 334

8 Process ................................................................................................................... 334

8.1 Installation of the measurement location ................................................................... 334

8.2 Sample preparation ..................................................................................................... 334

8.3 Sampling handling / sampling .................................................................................... 334

8.4 Storage of the samplers .............................................................................................. 334

8.5 Measurement and evaluation ...................................................................................... 334 8.5.1 Preparing of evaporation bowl .................................................................................................... 334

8.5.2 Calculating the results ................................................................................................................. 335

8.6 Disposal ...................................................................................................................... 335

8.7 Declaration and storage of results .............................................................................. 335

9 Quality assurance ................................................................................................... 336

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29 Definition of procedure

Determination of the dust deposit in the ambient air.

30 Application area of the procedure

Air measuring network and air quality information system

31 Scope of the procedure

Procedure served for the determination of the dust deposit in the ambient air. Dust deposit is

the dry state of the accumulated ambient substance input by the time of exposure.

Further, the procedure serves for sampling the dust deposition for future determination of

the content on heavy metals and on ionic compounds in the dust deposit.

32 Basic principals of the procedure

Ambient substance content will be collected over a defined measure time, usually of 1 month,

through exposure of the collect tray. Afterwards, the sample will be dried off and the dry

residue determined gravimetric. The result will be expressed in units g/(m²d) or mg/(m²d).

33 Reference to valid standards

The procedure will be described in:

VDI 2119, page 1 measurement of particle matter - overview (june 1972)

VDI 2119, page 2 determination of the particle matter deposition with collect plate

(procedure Bergerhoff) in glass or plastic (june 1972)

34 Devices

Sampling device consists of one collect plate in Polypropylen (NALGENE) and one stand

with basket guard. The extension of the wire basket works as protection against birds.

Collect plate consists of

A clear largeness of 111mm

One collect surface of 0,0096769 = 0,0097m²

One volume of 1l.

Further, for the working up the sample:

Evaporation bowl in Duran-Glass D = 95mm Article-Nr. 9000044

Drying cabinet „WTB binder“ with motorized air motion (air circulation/ adding

fresh air)

Analyze scale SARTORIUS RC 210P-OD1 (DualRange) clearness of display

0,02mg

Top pan scale SARTORIUS - Gold GC 1200 G

Screen according to DIN 4189, mesh size 1,12mm

Ultra sonic bath

Rubber scrapper

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35 Chemichals and auxiliary material

Ultra pure water

1%ige HNO3

36 Process

36.1 Installation of the measurement location

Device will be placed so that the collect surface horizontal in an distance from 1,5 - 2,0m over

the ground level. Obstacles that can disturb the air motion (for ex. trees and buildings) should

be far from the measurement device at least 10 times the distance between them and the

measure device.

36.2 Sample preparation

Clean the Bergerhoff-containers: clean in wash automat device, rinse with ultra pure

water, dry in drying cabinet at ca. 60 Grad C

Preparing for end of month for measurement technician, closed and labeled (site name

will be written with water proof pen on the recipients)

36.3 Sampling handling / sampling

Open and placement of the sample container on the measure location, record the

setting up time in the journal of the service personnel.

Setting up the closed sample container with 200 ml ultra pure water as blank sample in

X1

After 30 +/-2 days, sampling and closing of the samples inclusive blank value sample.

Setting up new containers

Sampling time will be registred in the journal of the service personnel and notified on

the sampling container (on the container using a water resistant pen)

36.4 Storage of the samplers

Ready containers for the production at the end of the month in room Y

Close the storage of the samples for determination of the dust deposition and cool it

for preparation of samples but not longer than 14 days.

Filled Bergerhoff containers, which are used for the ion determination, must be put

directly after arrival into the fridge

36.5 Measurement and evaluation

36.5.1 Preparing of evaporation bowl

Cleaned bowl identification, (for ex. X1 0601,it means. place-year-month), with 1%

HNO3 washing, drip down

Cool down 1 hour. at 105°C in dry cabinet, after 30 min. in scaling room (ca. 50%

rel. humidity)

Weighing on the analyze scale (SARTORIUS RC 210P-OD1), record tara weight (list

on the notebook at the scale)

Liquid transfer, dry off and scale

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335

When in the collect container are more than 120ml, than pre-evaporate in the dry

cabinet under 80°C

Bergerhoff containers in ultra sonic bath, so that the decanted dust deposit lifts from

the ground

Solid substances adhered on the container walls will be lifted with a rubber scrapper

and washed with ultra pure water

Put the evaporation bowl on the upper scale, press „Tara 0―

Container content through a screen according to DIN 4189 with a grid wide of

1,12mm in evaporation bowl, a good wash with ultra pure water and also put into the

evaporation bowl

Bring liquid quantity in the bowl to pre-evaporation or fill it up to 150 ml

Record liquid quantity (List in the notebook of the scale)

Screen after each sample and wash it with ultra pure water

Evaporate the sample in dry cabinet at 105°C, when the sampler is evaporated,

Leave it in the drying cabinet at least 1 hour at 105°C, after that let it cool down again

for 30 min. in the scale room, weighing and record the gross weight on the list

Evaporation bowls for the determination of the heavy metal content, will be covered

with a para-layer and put in the cabinet in the scaling room.

36.5.2 Calculating the results

The content evaluated as matter deposit (G) results from the difference between gross weight

and tara weight in g pro evaporation bowl. The general reference parameter will be calculated

as follows:

G

x = ---------

F * T

where

x matter deposit in g m-2

d-1

Vpr volume of the sample (150ml)

F collect surface in m² = 0,0097

G mass of the particle matter deposit in g

T sampling time (collecting time) in d days

36.6 Disposal

Generally the evaporation bowls are kept up to the end of the year in the scale room.

Evaporation bowls are cleaned in the laboratory‘s dish washing machine. Gross impurities

will be brushed away and disposed in domestic waste.

36.7 Declaration and storage of results

Results will be noted in the journal list. Additionally, the measurement results will be

recorded in the Excel-Table of the year.

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37 Quality assurance

Quality assurance contains practical measures in the laboratory for reaching and meeting the

required analyze quality. Here belong:

Periodical gauging of the analyze scale (to determine the dust deposit)

Placing, scaling and analyzing the blank value samples (for ulterior determination of

substance content (heavy metal, ions)

Statistical evaluation of the blank value sample with control card (at ulterior

determinations of the substance content (heavy metal, ions)

Disintegration of suspended matter samples and dust deposit samples for analyze using ICP-MS

Content

1 Definition ............................................................................................................... 337

2 Appliance area ....................................................................................................... 337

3 Scope ..................................................................................................................... 337

4 Basis of the procedure ............................................................................................ 337 4.1 Procedure principal ................................................................................................ 337

4.2 Terms and abbreviation .......................................................................................... 337

5 References to valid standards ................................................................................. 337

6 Devices (and accessories) ....................................................................................... 337 6.1 Device components of the microwave disintegration device ................................. 337

6.2 Devices for preparation/transfering of samples ..................................................... 338

7 Chemicals ............................................................................................................... 338

8 Carrying out ........................................................................................................... 339 8.1 Sample handling ..................................................................................................... 339

8.2 Further treatment of the samples ............................................................................ 339 8.2.1 Suspended dust filter .............................................................................................................. 339

8.2.2 Dust deposit ............................................................................................................................ 339

8.3 Disintegration ......................................................................................................... 340

8.4 Cleaning the containers and auxiliary material ...................................................... 342

8.5 Disposal .................................................................................................................. 343

9 Quality assurance ................................................................................................... 343

Guidelines for Ambient Air Monitoring Network

38 Definition

Disintegration of the dust deposition samples for analyze by means of ICP-MS.

39 Appliance area

This SOP applies for microwave system „micro PREP 1500―, produced by firm MLS

GmbH, with the trace metals (SM) of the dust samples and dust deposit samples.

40 Scope

The procedure described in this SOP converts the trace metals (SM) of the dust samples and

dust deposit samples in solutions that can be investigated using ICP-MS.

41 Basis of the procedure

41.1 Procedure principal

Trace metals contained in the suspended dust filter and dust deposit samples will be

converted into a solution using pressure disintegration with a mix of nitric acid –

hydrogen fluoride – and introduced to the ICP-MS.

41.2 Terms and abbreviation

Ultra pure water (RW)

Standard reference material (SRM)

Blank value (BW)

Polypropylen (PP)

Polytetrafluorethen (PTFE)

42 References to valid standards

- DIN EN 14902; Characteristic of ambient air – standardized procedure for setting

Pb/Cd/As/Ni as component of the PM10-Fraction of the suspended dust, August 2005

- VDI 2267 Blatt 15; Determination of matter in ambient air, measure the mass

concentration of As, Al, Fe, Cr, Ni, Cu, Zn, Cd, Pb, Pt, Rh, Ti, V, Se and Sb as

components of dust deposit using mass spectrometry (ICP-MS)

43 Devices (and accessories)

Pipette has to be use for quality relevant working steps, like using control and calibration

standards, establish sample dilutions etc.

43.1 Device components of the microwave disintegration device

Microwave system consists of:

- micro PREP 1500 (micro oven)

Guidelines for Ambient Air Monitoring Network

- TERMINAL 640 (command unit)

- easyCONTROL (steering software)

- ATC-CE-400 (automatic temperature control)

- Q/P-Sensorik for disintegration

- PRO-24M Rotor working place 70 ml incl. accessories with 24 places

- APCU-TR 41,5/70 preassure reactor (24 pieces)

Volume: 70ml

Max. working pressure: ca. 30 bar

Max. working temperature: 210 °C

43.2 Devices for preparation/transfering of samples

Measurement flask of PP, 25 ml, 3 pieces Each for BW-, SRM- and sample disintegration

Pipette (checked): 100µl-1000µl; 1000µl-5000µl

Sample bottles Weithals of PP, NALGENE, 30 ml

Injection bottles of PP or PTFE, 500 ml each for RW and HNO3 1%

Teflon twizers

Teflon wiper

Petri jacket with cap for dust filter

Exhaust steam glass jacket for dust deposition samples

Marker, water proof (for ex. Edding 3000)

Analyse balance, exactity at least 0,1 mg

44 Chemicals

RW , extracted from an installation of ultra pure water „SG― (conductibility < 0,06 µS/cm2)

HNO3 65% partial, definition: C - caustic

HNO3 65% ultra pure, identification: C, caustic

HF 40% ultra pure, identification: T+, C, very toxic, caustic

Washing solution (ca. 1 % HNO3)

Produced from 8 ml 65 % HNO3 ultra pure, filled with ultra pure water up to 500 ml

Identification: Xi - irritant

Clearing solution 1 (ca. 32 % HNO3)

Produced from 1000 ml 65 % HNO3 partial, filled with ultra pure water up to 1000 ml

Identification: C - irritant

Clearing solutin 2 (ca. 8 % HNO3)

Produced from 1000 ml 65 % HNO3 partial, filled with ultra pure water up to 1000 ml

identification: C – caustic

Guidelines for Ambient Air Monitoring Network

NIST-standard reference material (SRM) 1633a - Trace Elements in Coal Fly Ash, dry

2 hours at 105 °C

45 Carrying out

45.1 Sample handling

Department for 500 imission protection, disposal and recycling management is

responsible for sampling, transporting and storage the samples.

Samples and sampling data are taken from the measurement network.

45.2 Further treatment of the samples

Kettles are on the carrousel to be found. The pressure reactors are cleaned dried and numbered and will be put in the kettle on the right numbered position.

45.2.1 Suspended dust filter

- Filter with two cleaned Teflon-twizers will be bent and put in the numbered

disintegration containers according to the disintegration guide.

- 5 ml RW + 4 ml HNO3 + 0,4 ml HF

- For every disintegration series (up to 24 containers) at least a blank value and a SRM

will be disintegrated.

- Blank value disintegration: 1 empty filter + 5 ml RW + 4 ml HNO3 + 0,4 ml HF

- 1 SRM- disintegration: 20 mg SRM 1633a +5 ml RW + 4 ml HNO3 + 0,4 ml HF

- Close pressure reactors with teflon cap

- for 60 min. softening process

Disintegration of the suspended dust filter is with Program 1 carried out, which is saved in

the microwave system.

45.2.2 Dust deposit

- disintegration dust deposit stepwise with each 1 ml HNO3 3 times in the exhausted

steam and sent to pressure reactors

- final rinse each 3 ml RW 2 mal sent in the pressure reactors.

- introduce hydrogen fluoride (HF): 0,5 ml HF (country side)

0,8 ml HF (town)

- Classification of the samples to the pressure reactors using the disintegration

guide.

- For each disintegration series (up to 24 containers) will be at least one blank value and

one SRM desintegrated

- Blank value- disintegration: 1 empty container + 3 ml HNO3 , 6 ml RW and 0,5 ml HF

- 1 SRM- disintegration: 50 mg SRM 1633a +3 ml HNO3 , 6 ml RW and 0,8 ml HF

Guidelines for Ambient Air Monitoring Network

- close pressure reactors with teflon cap.

Disintegration of the dust deposition samples is carried out by the program 2, which is saved

in the microwave system.

45.3 Disintegration

- Starting the microwave device

- Close the kettles get the temperature sensor in the pressure reactor Nr. 1.

- Closed containers in the rotor chamber (numbering the pressure reactors must be in

accordance to the numbering of the carousel).

Kettles in carousel will be fastening with a cover plate and the carousel will be placed in the

microwave.

- Check: No metal objects are allowed to be placed in the microwave.

- Connect the signal of the temperature sensor at the sensor jacket in the inner

microwave.

- Round the samples of the carousel.

- Close the door.

- Select program.

- Program 1: „dust filter“

- Program 2: „dust deposition“

- Control program and start the program.

- While running the program, check periodically the course of the disintegration.

- After disintegration process (incl. integrated cooling time) the sample carousel will be

put in the outlet so that cooling will be completed.

- Cooling time in the outlet at least 2 hours.

- Turn off the microwave device, clean the interior of microwave with pulp and close it

afterward.

- After a sufficient cooling down of the samples, the containers can be open.

- ! Attention ! Nitric gases will be releases.

- Take the containers from the carousel and close precautious the kettle and remove it

- Open the closures of the pressure reactors and wash the hanging drops with washing

agent and put them in the reactor.

- Transfer sample solution with some washing solution in a 25 ml measurement flask

and rinse it with ultra pure water, fill it in the labeled sample bottles.

The clear disintegration solutions, produced in that way, can be used directly for determining using ICP-MS.

Guidelines for Ambient Air Monitoring Network

Tab. 1: Temperature-time-curve of both used microwave programs

- A) Program 1: „dust deposition“

step Ramp time [min] Ending temperature at the ramp [°C]

1 30 104

2 3 104

3 55 180

4 45 190

5 45 Cooling down

- B) Program 2: „dust filter“

step Ramp time [min] Ending temperature at the ramp [°C]

1 15 104

2 2 104

3 30 180

4 40 190

5 45 Cooling down

Guidelines for Ambient Air Monitoring Network

45.4 Cleaning the containers and auxiliary material

Cleaning the containers and auxiliary usig this scheme:

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45.5 Disposal

Residues of disintegration and chemicals will be collected and discharged in the waster water

through laboratory waste water (neutralization of acid), as far as no higher content of

polluting substances will be used. These highly polluted solutions will be disposed as

hazardous waste.

46 Quality assurance

Quality assurance will be guaranteed through following operations:

a) Carrying along a SRM to control the disintegration

b) Carrying along a blank value procedure

c) Prevention of discharged gas (element loss) from the disintegration container during

the disintegration using gas sensor

d) Equal temperature regime in the disintegratior using T-sensor in the reference sample

e) Working with very pure metal poor containers

f) Working with very pure metal poor chemicals

Guidelines on Air Quality Measurements by Passive Sampling

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Guidelines on Air Quality Measurements

by Passive Sampling Contents

Preface .......................................................................................................................... 347

1. Introduction ........................................................................................................... 347

2. Definitions ............................................................................................................. 347

2.1. Rate of collection by diffusion operations ............................................................. 347

2.2. Data availability ..................................................................................................... 347

2.3. Diffusion ................................................................................................................. 347

2.4. Diffusion coefficient .............................................................................................. 347

2.5. Air quality characteristics ....................................................................................... 347

2.6. Measurement area .................................................................................................. 347

2.7. Measured quantity .................................................................................................. 347

2.8. Measurement object ............................................................................................... 348

2.9. Measurement strategy ............................................................................................ 348

2.10. Measurement uncertainty ....................................................................................... 348

2.11. Indicative measurements ........................................................................................ 348

2.12. Stationary measurements ........................................................................................ 348

2.13. Passive sampler ...................................................................................................... 348

2.14. Random sampling ................................................................................................... 348

3. Fundamentals ........................................................................................................ 348

3.1. Measurement principles ......................................................................................... 348

3.2. Sampler types ......................................................................................................... 349

3.3. Influencing passive sampler measurements ........................................................... 350

4. Application of passive samplers in the field of air quality monitoring ...................... 350

4.1. Indicative measurements (Article 2 (26), 2008/50/EC) / Random measurements . 350

4.2. Stationary measurements (Article 2 para. 25, 2008/50/EC) / Continuous

measurements ..................................................................................................................... 351

4.3. Benefits of passive samplers / Fields of application .............................................. 351

5. Planning of air quality measurements by using passive samplers (creating a measurement plan) ....................................................................................................... 351

5.1. The task definition .................................................................................................. 352

5.2. Analysing previous knowledge .............................................................................. 352

5.3. Measurement strategy ............................................................................................ 352 5.3.1. Measurement area ................................................................................................................... 352 5.3.2. Measurement locations ........................................................................................................... 353 5.3.3. Measurement period ............................................................................................................... 353 5.3.4. Measurement times ................................................................................................................. 354 5.3.5. Sampling period...................................................................................................................... 354 5.3.6. Data availability...................................................................................................................... 354 5.3.7. Metrology ............................................................................................................................... 354 5.3.8. Performance characteristics .................................................................................................... 354 5.3.9. Quality assurance.................................................................................................................... 355 5.3.10. Organisation ........................................................................................................................... 355

6. Validation of measurement results ......................................................................... 355

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Annex A: Application Examples for Passive Sampler Measurements ............................... 357

Annex A1: The search for hot spots via passive sampler with respect to average NO2 exposure in an urban area ............................................................................................. 357

Annex A2: Evaluation of average benzene concentration by the use of passive samplers for the assessment of air quality according to EU Directive 2008/50/EC ............................... 360

Annex B: Methods for Measurement of Nitrogen Dioxide Concentration Within Ambient Air via Passive Sampler - Measurement Method Based on Saltzman Reaction ................ 361

1. Area of application, measurement methods, method parameters ........................... 361

2. Chemicals, Equipment ............................................................................................ 361

3. Sampling, sample conservation, sample storage ..................................................... 362

4. Preparation, storage and handling of standard solutions ........................................ 362

5. Sample preparation ................................................................................................ 363

6. Equipment adjustments ......................................................................................... 363

7. Measurement, assessment, results, documentation ............................................... 363

8. Quality assurance measures ................................................................................... 364

9. Equipment maintenance and maintenance intervals ............................................... 364

10. Troubleshooting advices ..................................................................................... 364

Annex C: Determination of Benzene in Ambient Air by Passive Sampler ......................... 365

1. The field of application ........................................................................................... 365

2. Equipment ............................................................................................................. 365

2.1. Sampling equipment ............................................................................................... 365

2.2. Sample preparation equipment ............................................................................... 365

2.3. Analytical equipment ............................................................................................. 366

3. Chemicals ............................................................................................................... 366

4. Sampling ................................................................................................................ 366

5. Preparation of standard solutions ........................................................................... 367

5.1. Fluorobenzene stock solution ................................................................................. 367

5.2. Dilutor of the internal standard .............................................................................. 367

5.3. BTX stock solution ................................................................................................. 367

5.4. Predilution .............................................................................................................. 367

5.5. Dosage of the internal standard .............................................................................. 367

5.6. External standard solutions .................................................................................... 367

6. Sample preparation of activated carbon samples .................................................... 367

6.1. Sample extraction process ...................................................................................... 367

6.2. Extraction of reference materials ........................................................................... 368

7. GC analysis process ................................................................................................ 368

8. Assessment ............................................................................................................ 368

8.1. Assessment through internal standard .................................................................... 368

8.2. Concentration of benzene in the air ........................................................................ 369

8.3. Calculation process ................................................................................................ 369

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9. Quality assurance measures ................................................................................... 370

9.1. Control of the calibration ....................................................................................... 370

9.2. Control of the reagent blank values ........................................................................ 370

9.3. Control of the field blank values ............................................................................ 370

9.4. Use of reference material ....................................................................................... 370

10. Documentation ................................................................................................... 370

10.1. Control cards .......................................................................................................... 370

10.2. Measurement processes .......................................................................................... 370

11. Parameters ......................................................................................................... 371

11.1. Field blank values ................................................................................................... 371

11.2. Detection limit of the overall process .................................................................... 371

11.3. Selectivity ............................................................................................................... 371

11.4. Measurement uncertainty ....................................................................................... 371

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Preface

This guideline defines the scope of application of the passive sampler within the field of air

quality measurements. Beneath the description of fundamentals and basic introduction of

relevant passive sampler types, potential applications will also be presented.

1. Introduction

With the help of passive samplers, gases can specifically be collected from the atmosphere.

Passive samplers do not require any active sampling operation and for this reason are far

more advantageous, when compared to continuously operated automatic gas analysers,

since they allow application under almost any circumstances and hence do not require any

complicated infrastructure. Another advantage is their cost efficiency, compared with

measurements carried out by active sampling. They provide an appropriate measurement

method for the technical analysis of the spatial distribution of air pollutants, covering a

sufficiently long averaging period. Though, an analysis of short time exposures with the help

of passive samplers is not possible in general.

2. Definitions

2.1. Rate of collection by diffusion operations

The measure of collection rate of a definite type of vapour from the atmosphere by the

diffusion sampler, expressed in terms of cubic centimetres per minute (cm3 · min−1).

2.2. Data availability

Percentage of the number of actually determined measurement values, within the given

number of values to be measured.

2.3. Diffusion

Material flow transport based on a concentration gradient.

2.4. Diffusion coefficient

The diffusion coefficient is a measure of the mobility of substance particles (molecules) and

enables the evaluation of the distance progressed within a definite time period. The SI unit of

the diffusion coefficient is m2s-1.

2.5. Air quality characteristics

The statistical parameter characterising the air quality at a measurement location or in a

certain area for a definite period of time and for a definite air impurity.

Remark: Statistical parameters are, for example, arithmetical averages, standard deviation, variation.

2.6. Measurement area

The area that is related to the results of the analysis.

2.7. Measured quantity

In case of passive sampler measurements, measured quantity is the mass concentration.

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2.8. Measurement object

The medium of measured quantity, in other words, the air impurity of interest.

2.9. Measurement strategy

The methodology for the spatial and temporal sampling of air impurities, for the achievement

of significant (representative) measurement results, within the context of the concerned

issue.

2.10. Measurement uncertainty

Parameter, being allocated to the measurement result, denoting the distribution of values,

which could reasonably be allocated to the measured quantity. In general, it means the

expanded relative measurement uncertainty within the range of an individual limit, in the

context of the air quality monitoring.

2.11. Indicative measurements

Measurements, which reach less severe targets compared with stationary measurements

(EU Directive 2008/50/EC).

2.12. Stationary measurements

Continuous or random measurements carried out at fixed locations for the evaluation of

values in compliance with relevant data quality targets of the EU Directive 2008/50/EC.

2.13. Passive sampler

Device, being capable of taking gas or vapour samples from the atmosphere, during which

the collection rate is controlled by physical processes like gas phase diffusion, through a

stagnant air layer or a porous material or permeation through a membrane, however without

active motion of air through the sampler.

2.14. Random sampling

Amount of interdependent measurement values of a measurement amount measured from a

defined population.

3. Fundamentals

3.1. Measurement principles

The working principle of passive samplers is based on the diffusion of air pollutants through a

concentration gradient. The concentration gradient is achieved by the adsorption of the

pollutant to an appropriate medium. After the defined time of exposition the passive samplers

are analysed in the laboratory and the concentration averages for the exposition time period

is calculated.

The mass of the pollutant to be measured is determined by using Fick‘s Diffusion Law, which

can be diffused to an appropriate sorbent within a definite period of time (see Figure 1).

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Figure 1: Schematic representation of the diffusion process (VDI 3869, Sheet 4)

In the ideal case, the concentration β1 at the inlet of the sampler is equal to the ambient air

concentration β0.At complete collection of the pollutant to be measured by the adsorption

medium the concentration β2 at sorption medium is equal to zero.

The inlet opening of the sampler with a cross section of APr defines the beginning of the

diffusion distance. The sorbent that decreases the concentration β2 of the pollutant to be

measured to zero by sorption or chemical reaction in ideal case, serves as the driving force

for the diffusion along the diffusion distance l.

The mass ms of the pollutant, which was adsorbed during the exposition of the sampler,

results as follows:

In practice, a non-ideal behaviour may arise from various factors, which should be expressed

as by the function FKin the equation above. For example, a restriction arises from the fact,

that the coefficient, normally being a constant diffusion coefficient D is used to evaluate the

pollutant concentration over the exposition time t, although being temperature und pressure

dependant in principle. In practice, it may also be necessary to interpret the measurement

results achieved with passive samplers (for example, by comparing with gas analysers or by

taking meteorological data as temperature, humidity, and air pressure into consideration).

3.2. Sampler types

A bunch of different sampler types are found in literature for different pollutants. Essentially

these can be differentiated as follows:

Plaquette type (batch sampler)

Tubule type (Palmes6 tubes)

Radial sampler

Since in air quality monitoring passive samplers are mainly used for monitoring average NO2

and benzene concentrations, vast experience is available. Passive samplers for

determiningNO2 and benzene concentrations are therefore discussed in detail within the

scope of this guideline (cf. Annex B, Annex C).

6E. D. Palmes und A. F. Gunnison, Personal Monitoring Device for Gaseous Contaminants Am. Ind. Hyg. Assoc.

J., 34, 78 - 81, 1973

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A good overview of different passive samplers can be found within the standard DIN EN

13528-3.

3.3. Influencing passive sampler measurements

Passive sampler measurements can generally be influenced by the following parameters:

Temperature and pressure: Since the diffusion coefficient is temperature and

pressure dependant, it may be useful to make a correction in this respect.

Humidity: High humidity can influence the adsorption capacity of hydrophilic sorbents

(for example activated carbon).High humidity can also change the sorption behaviour

of exposed inner walls of samplers of tubule type (Palmes tubes), or of the turbulence

barriers, particularly, if condensation occurs.

Wind and precipitation: The speed and direction of the wind can affect the

performance capability of a passive sampler, since turbulences that may occur may

influence the effective diffusion distance. In this regard, related turbulence barriers at

the inlet of a passive sampler are reinforced. Also, for reducing undesired

turbulences, as well as for protection against precipitation, passive samplers are

generally located in relevant weather protection containers. An overview to possible

containers can also be found in DIN EN 13528-3.

Due to aforementioned potential influences, passive sampler measurements should be

crosschecked with comparable measurement methods (for example continuously operated

automatic gas analysers).

4. Application of passive samplers in the field of air quality monitoring

Within the scope of air quality monitoring under the EU Directive 2008/50/EC, the utilisation

of passive samplers may be useful for a bunch of different tasks. As a rule of thumb, passive

samplers can always be used, if average pollutant concentration along a long period of time

is of prior significance. Long term limits for yearly averages for pollutants in gas form sulphur

dioxide (SO2), nitrogen dioxide (NO2), nitrogen oxide (NOx), and benzene are specified by

the EU Directive 2008/50/EC.In practice, vast experience is available for passive samplers,

especially for monitoring average NO2 and benzene concentrations.

4.1. Indicative measurements (Article 2 (26), 2008/50/EC) / Random

measurements

With respect to the monitoring of air quality, the use of „indicative measurements― is

prescribed in the Directive 2008/50/EC, if the concentration of the pollutant to be measured is

under the upper critical limit (Article 6, Paragraph 3) the measurement by passive sampler

cannot constitute an indicative measurement. In this case, a lower requirement for the

measurements is set with respect to expanded measurement uncertainty (Annex I).Indicative

measurements must fulfil an expanded measurement uncertainty within a 25% limit

(comparably, gas analysers in general must fulfil a 15% limit for this purpose).Indicative

measurements, with respect to the minimum duration requirement reduced likewise, have to

be construed as random measurements representing 14% a calendar year.

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4.2. Stationary measurements (Article 2 para. 25, 2008/50/EC) / Continuous

measurements

When passive samplers are used without intermittence (continuously), a stationary mea-

surement can also be carried out with their help, under the scope of the aforementioned

Directive, if for example assessment of yearly averages is concerned (for example NO2,

benzene).In so doing, the fulfilment of the requirements for data quality (especially for

expanded measurement uncertainty and for minimum data collection)must be ensured. In

addition, the equivalence of the applied methods must be demonstrated using relevant

reference methods, according to the guidelines „Guide to the demonstration of equivalence

of ambient air monitoring methods (01/2010)― of the „EC Working Group on Guidance for the

Demonstration of Equivalence‖. Insofar, a continuous monitoring of pollutants can also be

achieved with the help of passive sampler measurements, when compared with gas

analysers, indeed with a lower temporal resolution of measurement data.

4.3. Benefits of passive samplers / Fields of application

Depending on, whether passive samplers are used continuously or merely as random

measurements, knowledge can be gained by using them in the following tasks:

Preliminary assessment of air quality (pre-assessment)

Assessment of air quality in areas and conurbations (stationary measurement)

Monitoring air quality in areas, where no risks of exceeding limits are present

(indicative measurement)

Assessment of air pollution in the vicinity of point sources (traffic, industry)

Assessment of air pollution in ecosystems

Planning/optimisation of measuring networks (search for hot spots, control of location

criteria)

Collecting additional information as a part of causal analysis for action planning

Collecting additional information as a part of an approval procedure (background

exposure/pre-exposure).

Validation of models for the calculation of ambient air concentrations

Collection of data for scientific purposes

5. Planning of air quality measurements by using passive samplers

(creating a measurement plan)

A diligent measurement planning is a general condition, in order to attain results in air quality

measurements, the representativeness of which can be assessed with regard of spatial

dimension as well as of temporal dimension. This is also valid for measurements, which have

to be carried out with the help of passive samplers. As a part of measurement planning, the

type and scope of the measurements to be carried out have to be defined beforehand. The

starting point here is to clarify the issue with the help of measurements. A measurement plan

should discuss following points:

The task definition

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Analysing previous knowledge

Measurement strategy

Metrology

Quality assurance

Organisation

5.1. The task definition

Already when defining the task the following points have to be taken into account:

The reason why the measurement will be carried out

Requirements for the representativeness in spatial and temporal dimensions

(requirements at the measurement location, requirements for minimum data

collection, measurement uncertainty, minimum measurement duration),

Evaluation criteria to be applied (limits, target values, reference values)

Pollutants to be analysed

Metrological requirements,

Requirements for quality assurance and

Organisational requirements.

Furthermore, meteorological parameters (temperature, pressure, and humidity) should also

be collected in passive sampler measurements within the same measurement period, for

potential need of correction of measurement data later.

5.2. Analysing previous knowledge

Previous knowledge, which can be gained within the frame of measurement planning, could

help in making significant considerations for the measurement strategy (for example for

choosing measurement places, periods, and measurement times).It facilitates the

preparation and obviates the need for additional measurements.

In doing this, following information may help:

Measurement data available (air quality data and meteorological data),

Results from available dispersion calculations,

Information about the sources, which contribute to the occurrence of air pollution

within the measurement area (industrial facilities, small-sized industrial units and

household heating, traffic, natural sources).

5.3. Measurement strategy

5.3.1. Measurement area

The location and expansion of measurement area, in which air quality has to be assessed,

must be determined. In doing this, taking the pattern of use and topography into account on

large scale, and the building structure and the traffic flow on small scale, in a street canyon

for example, may be of key importance.

The measurement area can be determined as a part of the city area for example. Mutual

patterns of use may also be determined for example in terms of industry, traffic, dwelling, or

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leisure and recreation. In this, the measurement area may not be constituted of associated

partial areas.

5.3.2. Measurement locations

The number and site of measurement locations have to be derived from the definition of

task.In doing this, especially the requirements for spatial representativeness has to be

taken into account, for example the requirements of the EU Directive 2008/50/EC (Annex

III) at the measurement location. Here, previous knowledge (cf. 5.2) is of great significance,

since from such knowledge, considerations about the anticipated exposure level and the

spatial representativeness of possible measurement locations can be obtained.

Accessibility, safety and technical infrastructure of potential measurement locations

have also to be considered and should be clarified within the scope of a location visit.

When analysing larger measurement areas, under certain circumstances it may be

necessary to create different types of patterns of use by each measurement location. This is

of particular importance, when different levels of exposure are expected for the patterns of

use. The patterns of use as explained above may be the following:

Dwelling areas

Central areas within cities

Road traffic areas

Industrial areas

Manufacturing areas

Leisure and recreation areas

Rural background areas

Protected areas

The topographic conditions within the measurement area must also be taken into account

when choosing the measurement locations, since they influence the dispersion of air

pollutants. This applies to both small scale and large scale evaluations.

Besides topographic conditions, meteorological conditions do also influence the distribution

of air pollutants. For this reason, meteorological conditions prevailing at the measurement

area should be considered. The fact that the meteorology itself may be influenced by

topographic conditions should also be taken into account.

Finally, the distribution of relevant sources around a potential measurement location should

be considered. In connection with this, the results of dispersion calculations can be

supported by the choice of measurement locations.

5.3.3. Measurement period

Measurement period is the duration of the measurement program. It has to be defined within

the measurement plan. For stationary measurements the measurement period is normally

specified as one year under the EU Directive 2008/50/EC.

For indicative measurements, the measurement period can be shortened regarding relevant

requirements

If under the definition of task special meteorological conditions of interest are present, this

has to be taken into account as well when setting the measurement period.

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5.3.4. Measurement times

Progressive collection by passive sampler is possible and can hence be construed as

continuous measurement. When compared with gas analysers, the temporal resolution of

measurement data is obviously lower in this process.

Frequently air quality characteristics show typical temporal dependence, for example in form

of daily, weekly, or yearly cycles. Secure and provable knowledge about such temporal

regularities can be used, to temporally limit and by this manner cost efficiently optimise the

measurement burden.

If for example the entirety researched covers the temporal distribution over one year, this

knowledge of yearly cycle can be used to calculate yearly parameters from shorter

measurement periods (random sampling) by extrapolation, if such an extrapolation is

sufficiently reliable.

5.3.5. Sampling period

Sampling period of passive sampler (exposition) is determined primarily, according to the

collection capacity of the sampler and in consequence also according to the expected level

of exposure. Under the definition of task, a minimum data collection, consequently defining

the sampling period, can also be determined. Organisational aspects, as time and human

resources for example, the sampling and following analysis in laboratory must also be

considered. Since the sampling period plays a role in the calculation of the concentration, a

protocol has to be kept accordingly.

5.3.6. Data availability

Since failures of metrology for sampling and/or analysis cannot be excluded, in order to fulfil

the measurement requirements, minimum availabilities have to be determined - if not already

prescribed by law - according to the selected measurement times. Normally for random

measurements, alternate dates can be set, in order to achieve the prescribed number of

samples. For temporally continuous passive sampler measurements, measurement value

failures can seldom be minimised by short-term use of alternate samplers, since failures can

be identified at the earliest during the next sample change7.

5.3.7. Metrology

The choice of passive sampler types to be used and following analysis in the laboratory is

primarily determined according to the individual pollutant to be analysed. Examples for the

measurement of NO2 and benzene via passive sampler can be found in Annex A. Further

examples can be obtained from the standard DIN EN 13528-3.

Normally passive samplers are exposed for a time period changing between one and four

weeks. Maximum temporal resolution of measurement data is hence primarily shaped by the

type and duration of sampling, which are necessary to reach prescribed performance

characteristics and pre-eminently to reach the detection limit.

5.3.8. Performance characteristics

In many cases passive sampler measurements are not standardised yet. In such cases the

measurement methods used have to be completely documented in a similar way by the user,

if not otherwise provided by the commercial supplier. The comparability with the reference

method has to be described. The European Standard DIN EN 13528-3 prescribes the

7Passive samplers installed in measurement area should be labeled with relevant contact data, by the institution

carrying out the measurement.

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requirements and test methods for the determination of method parameters of passive

samplers, which are used for determination of the gas and vapour concentrations in ambient

air. For all method parameters, protocols must be held, which are later to be attached to

future result reports.

5.3.9. Quality assurance

For the qualitative assurance of measurement results, comparative measurements have to

be carried out at chosen locations, which are to be compared with other measurement me-

thods (for example with gas analysers).If passive samplers are to be used for stationary

measurements under the scope of the EU Directive 2008/50/EC, the equivalence of the

applied methods must be demonstrated using relevant reference methods, according to the

guidelines „Guide to the demonstration of equivalence of ambient air monitoring methods

(2008/50/EC)― of the „EC Working Group on Guidance for the Demonstration of

Equivalence―8.Since it may occasionally be necessary that the results of passive sampler

measurements be readjusted according to the meteorological conditions, average

meteorological conditions (temperature, pressure, relative humidity) should also be collected

during the passive sampler measurement period. Furthermore, the quality control measures

have to be oriented towards the provisions of DIN EN ISO/IEC 17025.

5.3.10. Organisation

In order to ensure a smooth process of sampling and analysis, the responsibilities and time

schedules should be set within the measurement plan.

6. Validation of measurement results

As already described in chapter 5.3.9, the passive sampler measurements allow validation

by direct comparison with other measurement methods. As an example, a comparison of

NO2 measurements for a 14-day random sampling by passive sampler with the

measurements of a relevant automated NOx-analyser is shown in Figure 2.This figure

demonstrates that in both measurement methods14-day average values have fitted in good

agreement.

8The EC Working Group on Guidance for the Demonstration of Equivalence has made an excel sheet available,

with which the equivalence has to be tested and for example also the expanded measurement uncertainty can be calculated (http://ec.europa.eu/environment/air/quality/legislation/assessment.htm)

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Figure 2: Example of comparison of passive sampler measurements with a NOx-analyser during a 14-day exposition

In Annex B and C, examples for the assessment of NO2 and benzene passive samplers are

included. Here, examples for operating procedures from Federal German AQ monitoring

networks, which are related with usual practices and measurement equipment in the

laboratories, are provided.

In order to be able to prepare the Standard Operating Procedures (SOP) these operating

procedures must be adapted to the conditions of relevant laboratories.

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Annex A: Application Examples for Passive Sampler Measurements

Annex A1: The search for hot spots via passive sampler with respect to

average NO2 exposure in an urban area

The task definition:

In the following example, the task was to detect the street sections in a metropolitan district,

exposed with respect to average NO2 concentration. For this purpose, first of all a simple

measurement method should be used in order to be able to find an appropriate location later

for a measurement container (traffic measurement station).

Analysing previous knowledge:

With regard to spatial NO2 distribution, no results from relevant dispersion calculations have

heretofore existed yet. The only knowledge present was data about traffic volumes as well as

about the planning structure.

Measurement area:

The measurement area covered busy streets of heavy traffic within the urban area.

Measurement locations:

Firstly basing on the data about traffic volumes and the planning structure, a series of

potential measurement locations were selected. During on-site visits at potential locations –

taking the infrastructure (suitable alternatives for installing the passive sampler in the street

area), the requirements of the Directive 2008/50/EC at measurement locations and local

characteristics into account – a total of six locations were selected, at which passive

samplers would be used. The passive samplers were installed with the help of a U-tube on

present street lamps at 3-meter height9.

Measurement period, measurement times, sampling duration, data availability:

Since the measurements, which should be used for calculating the yearly averages of NO2

exposure, the measurement period was chosen as one calendar year. The sampling duration

of a single individual passive sampler lasted for 14 days. The passive samplers were

continuously interchanged, so that temporally complete sets of data of 14-day averages over

a period of one calendar year were available as a result. Since only very rarely failures were

recorded, the data availability for the measurement period remained above 90%.

Metrology:

Passive samplers of Palmes 10 type were used. Each weather protection container was

equipped with four sampler tubules to evaluate the NO2 concentration (four-fold assay) and

two sampler tubules to evaluate a field blank value.

9The EU Directive 2008/50/EC foresees a sampling in a height between 1.50 m and 4 m. To protect from

vandalism an installation of the passive sampler at 3 meters proved itself. 10E. D. Palmes und A. F. Gunnison, Personal Monitoring Device for Gaseous Contaminants Am. Ind. Hyg.

Assoc. J., 34, 78 - 81, 1973

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Figure 3: Example for a NO2 passive sampler of Palmes type

The analytic assay of NO2 concentration was completed after the 14-day sampling period in

the laboratory, according to the method described in the annex used to evaluate the NO2

concentration by the passive sampler.

Quality assurance:

In order to achieve quality assurance for the passive sampler, comparative measurements

between NO2 passive samplers and NOx-analysers were carried out under simultaneous

measurement programs in other cities. Using the meteorological data (temperature, air

pressure, humidity), a correction function for the measurement results of the passive sampler

of the following types was compiled:

NO2_corrected = A*NO2_uncorrected + B*temperatureaverage + C*airpressureaverage+ D*humidityaverage

The factors A to D were determined with the help of comparison data in a multiple linear

regression. After applying the correction function, the measurement methods compared

showed a very good correlation (see figure 2).

Results:

Basing on the passive sampler measurements carried out, a hot spot could be identified with

respect to NO2, at which later a measurement station for continuous monitoring of the NO2

concentration was built.

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Figure 4: Measurement results from NO2 passive sampler measurements (14 day averages)

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Annex A2: Evaluation of average benzene concentration by the use of

passive samplers for the assessment of air quality according to EU Directive

2008/50/EC

Task definition and previous knowledge:

In this present example the average benzene concentration is monitored with the help of

passive samplers. Benzene values within the test area are mostly underneath the lower

critical limit, and rarely between the lower and the upper critical limits for benzene. For this

reason, the continuous benzene measurements carried out earlier by continuously operated

gas analysers were replaced by passive sampler measurements.

Measurement area:

The measurement area covered the Federal State Niedersachsen (Germany).

Measurement locations:

Benzene passive sampler measurements were used at present measurement locations of

the measurement network across the Federal State. The locations are on busy traffic routes

as well as within urban, suburban, and rural background areas. The samplers are installed at

an approximately 1.70 m height within the area where the gas sampling probes are located.

Measurement period, measurement times, sampling duration, data availability:

Since the measurements should be used for calculating the yearly averages of benzene

exposure, the period is chosen as one calendar year. The sampling duration of a single

individual passive sampler is normally 30 days. The passive samplers are continuously

interchanged, so that temporally complete set of data of 30-day averages over a period of

one calendar year is available as a result. Since generally only very rarely failures are

recorded, the data availability remained normally above 90 %.

Metrology:

In the measurement program described, passive samplers of type ORSA 511 are used.

These are of tubule type, which are filled with activated carbon. Both ends of the tubules are

sealed with cellulose acetate filters.

The analytic assay of benzene concentration was completed after the 30-day sampling

period in the laboratory, according to the method described in the annex used to evaluate the

benzene concentration by the passive sampler.

11ORSA 5 is an example for an appropriate commercial product (manufacturer Dräger AG, Lübeck; This

example information is to provide knowledge to the user in this guideline and it cannot be construed as the acceptance of the product mentioned by CEN or any other.

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Annex B: Methods for Measurement of Nitrogen Dioxide Concentration

Within Ambient Air via Passive Sampler - Measurement Method Based on

Saltzman Reaction

1. Area of application, measurement methods, method parameters

This operating procedure applies to nitrogen dioxide measurements in ambient air (air

quality) by passive sampler.

Passive sampling is done through diffusion sampler, the adsorption agent of which being

triethanolamine binding to the nitrogen dioxide within the ambient air. The adsorbed amount

of NO2 is extracted and reacts with N-naphthalen-1-ylethane-1,2-diamine dihydrochloride (N-

1-naphthylethylenediamine dihydrochloride, NEDA) and sulphanilicacid, yielding a pink

coloured diazodyeby the so-called Saltzman Reaction.

Method parameters:

The specifications of passive sampler are stated by the manufacturer (in this case Passam

AG12) as follows:

Measurement range: 1 - 200 µg/m³ (exposition time 1 - 4 weeks)

Detection limit: 0.64 µg/m³ (for a measurement period of 14 days)

Own evaluations of parameters related to the analysis steps (evaluated using calibration and

blank value method) show a detection limit of less than 0.01 µgNO2/2ml, being equivalent to

0.23 µg NO2/m³ for an exposition time of 4 weeks.

Such evaluation of parameters is repeated at every 20th series of measurement or latest

after 5 years.

Working range for a 4-week exposition time: 1 - 45 µg/m³ NO2

With a double reagent addition

or by halving the exposition time 1 - max. 90µg/m³ NO2

Dueto simplified sampling, the results are restricted in terms of reliability (indicative

measurement method).The method was tested by comparing with continuous measurement

equipment at air quality network stations.

2. Chemicals, Equipment

Nitrite standard 1000 mg/l

Sulphanilicacid (for analytical purpose)

NEDA

o-phosphoric acid (85%)

NO2 passive sampler and diffusion barriers

12Passam AG, Switzerland; This example information is to provide knowledge to the user in this guideline and it

cannot be construed as the acceptance of the product mentioned by CEN or any other

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Disposable cuvettes of 1cm layer thickness

Shaker

Timer

Spectral photometer

3. Sampling, sample conservation, sample storage

The passive samplers are hung at selected measurement locations at approximately 3 m

height (or at the height of comparison measurement equipment), protected from weather

conditions in special open to the bottom sampling apparatus. Red sealing caps of samplers

are replaced with diffusion barriers (bored up sealing caps with inserted filter) and these are

hung with a white cap looking up into the container. After the measurement period is

completed these are sealed again with red cap.

Remark:

At some measurement locations, especially on streets with higher traffic volume ,the findings

may be higher when compared with continuous measurement equipment. Here, the incident

flow behaviour may be crucial. In order to attain a stilled airflow within passive samplers,

which is necessary for using relevant diffusion laws, diffusion barriers can be installed on the

samplers. These are filters or chips, which lengthen samplers, and by this manner change

the constant Ksampler For this reason, their usage has to be noted on the sampling protocol

under all circumstances, and taken into consideration during assessment.

The measurement location, the sample number, mounting, demounting dates and times, and

eventually the sampler numbers have to be stated on the sampling protocol.

The exposed samplers have to be kept in refrigerator in dark and may be kept in these

conditions for up to 4 months. The samplers may be kept in storage for up to 12 months

before using.

4. Preparation, storage and handling of standard solutions

For the preparation of solutions only ultra-pure water is used.

Colour reagent:

Solution 1: In a 2000ml Erlenmeyer flask 25ml o-phosphoric acid (measuring cylinder)

and 10g sulphanilicacid are added onto approx. 500ml ultra-pure water. Then ultra-pure

water is added to make 1000ml of solution, and the solution is brought to boil under the fume

hood.

Solution 2: 72.8mg NEDA are solved in 100ml ultra-pure water by stirring (measuring

cylinder).

After cooling down, both solutions are mixed in a brown glass bottle to the combined colour

reagent. The solution should be used at earliest after 24 hours.

The combined colour reagent can be stored in a well-sealed brown glass bottle at room

temperature for at least 3 months.

Calibration solution:

Fill a 1000ml volumetric flask beforehand with approx. 900ml water and keep it

at20°C.Oneml of the nitrite standard solution is added onto it, and is filled up to the mark.

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The calibration curve consists of 9 concentrations and is based on 2ml, since 2ml reagent is

added into the sampler. If doubled amount is used (max. filling volume sampler), this dilution

factor must be taken into account in the calculation.

5. Sample preparation

Before the measurement of the samples, a calibration curve must be drawn. For this

purpose, 9 concentrations of 3 charges each are produced from a fresh nitrite standard

solution. Volumes pipettet into 25ml volumetric flasks are filled up with colour reagent up to

the full-mark. Shake well! Earliest after 15 min standing time, extinction is determined at

540nm at photometer in disposable cuvettes against water as the comparison medium. The

calibration curve should be measured before the colour reagents are added onto the

samples. If the slope of the linear function remains within the tolerance range of the target

value card (see quality assurance measures, chapter 8), continue with the analysis of the

samples.

6. Equipment adjustments

Photometer:

After turning the device on, an initiation program runs automatically, which is completed in

short order, and the photometer is set back to normal measurement condition.

The wavelength input is entered. The field abs (absorption) must be activated, in order to

obtain the results within the extinction. Same type of cuvette has to be mounted to both of

the ray paths within the photometer. Before the measurement is started, both cuvettes are

filled with ultra-pure water, in order to make the zero adjustment of the device by the auto

zero button.

7. Measurement, assessment, results, documentation

The analysis of the samples:

The desorption of NO2 is done by the addition of the colour reagent into the sampler.2ml (or

4ml at higher concentrations) of combined colour reagent is added directly into the sampler

using an Eppendorf pipette. It must be shaken vigorously, preferably on a shaker, at least for

1 minute, and a standing time of at least 15 minutes before the measurement has to be

complied with.

The results obtained should be entered into an excel spread sheet.

Sampler constants are calculated from the ratio of tubule length to the inner cross sectional

area.

The exposition time, pressure and temperature are specified in the protocol:

The diffusion coefficient for NO2 can be obtained from the chemical physical tables listed as

0.154 cm²/s.It is corrected to the conditions at 20°C.

m * K Sampler * 1013 * T Sampling * 1000000

correc.diff.coefficient * Expos.in s * p Sampling * 293,15 c =

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A blank value representing an not sampled tubule from same charge used for sampling is

also measured and handled together with the sample. The results of field blank values must

not be subtracted from the samples.

8. Quality assurance measures

Since this is a case of an indicative measurement method, usual quality assurance measures

are not applied here. However, in order to identify and avoid eventual system fluctuations, a

target value card is kept for the reproducibility of the calibration function. The slope average

value among 16 functions is evaluated and with a tolerance of approx. 5%, equivalent to

twice the standard deviation, upper and lower target values are set.

If the calibration series falls outside of the limits, the method manager (head of laboratory)

must be notified about the situation.

A target value card is kept for field blank values. Exclusion limits are determined as three

times the standard deviation of the present results of the field blank values. If the calibration

series remains above this limit, the method manager (head of laboratory) must be notified

about the situation.

The evaluation of detection limit (10 point calibration) as well as the measurement

uncertainty (assessment of repeat determinations) are repeated at every 20thseries of

measurement or latest after 5 years.

9. Equipment maintenance and maintenance intervals

The maintenance of the photometer is not carried out on a regular cycle. Repairing or

replacement of accessories are documented within the equipment handbook and those

related with the quality assurance measures are documented on control cards.

10. Troubleshooting advices

Explicit sample tracking must be ensured.

Cuvette direction within ray path must be taken into consideration for semi-micro

cuvettes.

During the mounting of diffusion barriers, the direction of thefilter insert must be

checked for being correct

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Annex C: Determination of Benzene in Ambient Air by Passive Sampler

1. The field of application

The method described below enables sampling and quantitative assay of benzene and of

other BTX aromatic compounds (toluene, ethylbenzene, and xylenes) in ambient air within

the air quality concentration range. The method is based on DIN EN 14662-5 (August 2005).

2. Equipment

2.1. Sampling equipment

ORSA 513 – Diffusion sampler with holder and rain protection cover as necessary

2.2. Sample preparation equipment

Sample glasses, 4 ml; screw caps with silicon/PTFE sealing

Volumetric pipettes, 2 ml, (class A)

Volumetric flasks, 10 ml, (class A)

µl syringes (gastight)

CERTAN14 sample vials, 4 ml

13ORSA 5 is an example for an appropriate commercial product (manufacturer Dräger AG, Lübeck;. This

example information is to provide knowledge to the user in this guideline and it cannot be construed as the acceptance of the product mentioned by CEN or any other. 14The properties of the patented CERTAN capillary bottle depend on the unique way in which the glass bottle,

capillary and screw cap closures have been engineered. The 1.2mm diameter and 28mm long capillary works as a re-condensation zone for any vaporised solvent. The reduced surface area inside the cap ensures a more efficient sealing of the bottle. It also minimises the change of contamination from the cap insert. The CERTAN bottle combines the advantages of a sealed ampoule with the flexibility of a screw cap bottle or a septum vial. Both cap and insert have been manufactured in materials, which have been tested to ensure they retain their sealing properties, even with critical solvents such as diethylether.

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Screw cap vial 2 ml

Screw caps

Silicon/PTFE sealing

Analytical balance, readability 0.1 mg

2.3. Analytical equipment

Gas chromatograph Agilent 6890, with split/split less injector and FID, or similar Glass insert Auto sampler

3. Chemicals

Carbon disulphide, low benzene

Fluorobenzene, >99,5% (GC)

Benzene, 99,97% (GC)

BTX adsorbed onto activated carbon, certified reference material

4. Sampling

In order to enrich benzene, passive samplers of type ORSA 5 (Dräger) are used. The

exposition time is normally 30 days. With each sampling series, at least one unused tubule

as field blank value is also carried along during the transport.

At the sampling location the ORSA 5 sampler is taken from the glass transport container,

placed into the holder and covered with a rain protection before being exposed to the

ambient atmosphere. Date, starting time, and ambient conditions have to be mentioned in

the sampling protocol. In order to avoid contaminations, the tubules should not be labelled

with markers.

After the sampling is completed the tubules are taken about of the holder, placed into the

transportation bottle, tightly closed, and kept under protection against external influence until

analysing, in order to avoid subsequent contamination. At the end of the sampling, date and

daytime data are recorded on the protocol.

The samples are recorded into the received samples book, after entering into the laboratory,

and kept within the sample storage locker together with the field blank values until they are

analysed.

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5. Preparation of standard solutions

5.1. Fluorobenzene stock solution

20 µl fluorobenzene und 2 ml carbon disulphide are added into a 2 ml screw vial. The

solution is filled into a 2 ml CERTAN vial and kept in refrigerator for further use for maximum

6 months at 4°C.

5.2. Dilutor of the internal standard

100 µl of stock solution from 5.1 is added onto 500 ml carbon disulphide. Fluorobenzene

concentration in this dilution (dilutor) is 2 µg/ml. It can be kept within a brown bottle for

maximum 6 months.

5.3. BTX stock solution

A mass of approx. 150 mg benzene is added into a 10 ml volumetric flask, and is filled up to

the mark with dilutor and thus constitutes the BTX stock solution. If beneath benzene

further aromatic compounds have to be assayed, approximately 150 mg is weighed for each

additional component to be calibrated and added into the volumetric flask.

5.4. Predilution

25 µl of stock solution are added into a 25 ml volumetric flask, and filled up to the mark with

dilutor and thus constitutes the predilution.

3 ml of the predilution is filled into a 4 ml CERTAN vial and kept in refrigerator for further use

for maximum 4 months at 4°C.

5.5. Dosage of the internal standard

The concentration of the internal standard within the calibration solutions and activated

carbon extracts is equivalent to 2 µg/ml. The volumes of stock solutions of the external

standards, defined for this purpose are filled using the dilutor (5.2).Activated carbon samples

are taken into the 2.0 ml dilutor (5.2).

5.6. External standard solutions

For each calibration concentration the content of an unused activated carbon tubule is filled

into a 2 ml screw vial and 2 ml of dilutor are added. Volumes of BTX predilution defined by

dosage are used to produce calibration solutions of external standards of at least five

concentrations within the range between 0.1 µg/ml and 1.5 µg/ml.

6. Sample preparation of activated carbon samples

6.1. Sample extraction process

The content of collection tubule are filled into the sample glasses for desorption, and each of them is

covered with 2 ml dilutor. Then the glasses are immediately sealed with a screw cap. After approx. 30

min and with occasional agitating, the extract is separated from the activated carbon, by transferring it

into the auto sampler sample glasses. The glasses are sealed with screw caps and silicon/PTFE sealing.

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6.2. Extraction of reference materials

The content of reference material tubule are extracted together with the content of an unused

ORSA 5 tubule, in the same way as the samples were extracted. In order to obtain a

benzene concentration – in the extract – within the working range of the calibration curve,

thereference sample is extracted with 10 ml dilutor regardless of 6.1.

7. GC analysis process

The initial start up and operation of GC equipment is done according to the operating

instructions of the manufacturer.

Chromatographic conditions

Injector: 180°C, split less injection

Auto sampler: 10 µl Hamilton syringe, syringe filling: 1 µl

Purge: 40 ml/min after 0.4 min

Carrier gas: Helium

Flow pattern: 0 - 0.7 min 4.0 ml/min 0.7 - 10 min 1.2 ml/min 10 - 20 min 1.8 ml/min

Column oven: 34 °C, keep for 0.7 min 3 K/min to 60 °C, 12 K/min to 100 °C, 15 K/min to 150 °C keep for 4 min, cool down to 34 °C

Detector: 220 °C

Process gases FID: Hydrogen 40 ml/min Air 400 ml/min N2 (make up) 25 ml/min

8. Assessment

8.1. Assessment through internal standard

At least five solutions of external standards in different concentrations, brought to the same

concentration as internal standards, are injected into the GC system.

The determination of response factors for benzene is done with the help of standard

solutions within the same medium (activated carbon/CS2) as with the sample preparation,

where an analogous establishment of equilibrium of the analyte concentration between both

mediums is assumed. By this manner, the desorption yield is contained within the calibration,

and must not be taken into account anymore in later calculations.

The assessment is made by the integrating unit using the analysis function by peak area comparison

with an internal standard.

The mass of benzene within the activated carbon extract (ng/sample) is calculated according

to the equation(1):

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ISE

EISEEE

A

VCAm

(1) AE = Peak area for benzene in chromatogram of the activated carbon extract

AISE = Peak area for benzene in chromatogram of the standard

CISE = Concentration for benzene in standard, [ng/µl]

VE = Volume of activated carbon extract, [µl]

mE= Mass of benzene within activated carbon extract, [ng]

8.2. Concentration of benzene in the air

The concentration of benzene (µg/m3)in the air referring to the standard conditions (20°C

and 1013 hPa) is calculated according to the equation (2):

106

106 (2) C0 = Concentration of the measured pollutant [µg/m3]

m = Mass of analytes, which are determined gas chromatographically [ng]

D298 = Diffusion coefficient (benzene: 0.0859) at 25 °C and 1013 hPa [cm2/sec]

DT = Corrected diffusion coefficient [cm2/sec]

K = Device constant = 0.8 cm-1

t = Exposition time [sec]

T = Sampling temperature [K]

P = Sampling air pressure [hPa]

8.3. Calculation process

The assessment and calculation of the internal standard is carried out with the help of the

Software Totalchrom Workstation.

Each sample is analysed 2 times and the average is found.

Pressure and temperature correction of the diffusion coefficient

Calculation of the pollutant concentration

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For the calculation of the air concentration the mass of benzene (ng/sample), the diffusion

coefficient for benzene, exposition start and end (date and day time) as well as the average

temperature of the measurement station are entered into the designated cells in the

respective excel template of. The air concentration (µg/m3) is calculated using the formulas

present in the template.

9. Quality assurance measures

9.1. Control of the calibration

With each sample series, five concentrations within the range between 0.15 µg/ml and 1.5 µg/ml areanalysed and a new calibration curve is drawn.

9.2. Control of the reagent blank values

Each new carbon disulphide charge has to be checked for impurities by GC analysis before using. Carbon disulphide used for the desorption of benzene should not contain any compounds, which could disturb the analysis of benzene. The benzene concentration of the carbon disulphide used must be under 0.1 µg/ml.

9.3. Control of the field blank values

For each sample series, at least one field blank value should be carried and analysed, in order to identify the contamination of the activated carbon during transport and storage. If the chromatogram has a peak at the retention time of benzene and the peak area shows a concentration above 0.1 µg, the results of the related field samples have to be discarded. The reasons must be identified and these must be eliminated by corrective actions. Blank values should not be subtracted from the measurement results of the samples.

9.4. Use of reference material

For the verification of the accuracy of the ORSA measurement method, a reference material sample is analysed together with the ORSA samples every two months.

10. Documentation

10.1. Control cards

The results of the field blank values test are recorded into the control cards.

10.2. Measurement processes

All analysis, disturbances, maintenance work etc. have to be recorded into the equipment handbook.

Analysis reports, analysis sequence, and the table for the calculation of calibration concentrations are printed and filed together with the sampling protocol in the measurement reports folder for the actual year.

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11. Parameters

11.1. Field blank values

The blank values for benzene should remain within the range < 0.02 - 0.05 µg/sample, in the measurement series carried out up to date. The blank values of a measurement series should be <10% than the smallest value measured among the samples.

11.2. Detection limit of the overall process

The detection limit over the signal-to-noise ratio is calculated as 3 times the average noise at retention time of benzene ± 10 times the peak width at half peak height. For benzene the detection limit (at 30 days exposition time and 2 ml desorbing agent) is approx. 0.04 µg/m3.

11.3. Selectivity

Under the conditions described above the BTX aromatic compounds, the samples collected at traffic stations are sufficiently good for differentiating them from other components and identifying them individually. When additional data are available for emissions, which do not originate from street traffic, a control analysis has to be carried out with a column of different polarity.

11.4. Measurement uncertainty

The expanded measurement uncertainty Ue is calculated from the data for the determination of accuracy (UCRM) and the data from the double determinations (UD) according to EN ISO 20988 (calculation method A5 and A6). The measurement uncertainty from double determinations is referred to the average concentration range and not to the limits or threshold values. Ue = √ uCRM² + uD²

Components UCRM (%) UD (%) Ue(%)

Benzene 1.1 5.9 6.0