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INDOOR AIR QUALITY : INDOOR AIR QUALITY TOMAXIMISE PRODUCTIVITY

26TH March 2013

By: Ir. Ng Yong Kong

1. Indoor Environmental Quality (IEQ)

• Primary areas of concern in IEQ– Air Quality and Ventilation– Thermal Comfort: Design &

Controllability of Systems– Lighting and Visual Perception – Acoustic and Noise Comfort

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1. Indoor Environmental Quality (IEQ)

• More than just Indoor Air Quality (IAQ) • HVAC system provides a comfortable

environment for building occupants and

contributes significantly to Indoor Health

Environment

• IAQ Definitions by WHO - The physical and chemical nature of indoor

air, as delivered to the breathing zone of building occupants, which

produces a complete state of mental, physical and social well-being

of the occupants, and not merely the absence of disease or infirmity.

Good IAQ may be defined as air with no known contaminants at harmful concentrations. Common contaminants or pollutants include gaseous pollutants, such as carbon dioxide (produced by occupants and from combustion appliances), volatile organic compounds (released by carpet glue and other materials), odoursand particulates.

Good IAQ is essential to ensure the health and comfort of occupants.

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Factors that increase our exposure to indoor air pollutants

Reduced ventilation rates to conserve energy

• The use of synthetic building materials and furnishings

• The use of chemically formulated personal care products, pesticides, printing inks, and household cleaners.

Pollutant Sources

Indoor sources • Combustion sources • Building materials

and furnishings• Asbestos-containing

insulation • Household cleaning

products• HVAC systems• Occupants and activities

Outdoor sources

• Radon

• Pesticides

• Outdoor air pollution

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Why do we “air-condition” our buildings?

• Control Temperature

• Control Humidity/Moisture

• Control Air Movement

• Control Air Quality

• Control Noise and glare

• Control the environment

• increase productivity and comfort

Pollutants Types

Sick building syndrome (SBS)

• Sick building syndrome (SBS) is a condition that may be experience by occupants of the buildings. The symptoms include headaches, eye strain and lung irritation. Usually the symptoms disappear when the affected person leaves the ‘mal-functioning’ building and are of short duration.

• Sick building syndrome occurs in the buildings which may have a number of defects, including inadequate ventilation, low light levels and /or flickering light fittings, excessive odours, high ambient noise levels, lack of local controls and other factors.

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Pollutants Types

Sick building syndrome (SBS)

• Typically inadequate ventilation may be due to insufficient supplies of fresh air, excessive recirculation of air, poorly maintained air handling units (i.e. filters not replace when needed) or a poorly designed and / or installed ductwork system.

• Low light levels are the result of light fittings not being replaced, the wrong type of fitting being used, poor lighting controls and / or insufficient numbers of light fittings being installed. Poor levels of daylighting can have the same effect.

Pollutants Types

Sick building syndrome (SBS)

• Excessive odours may be due to a poorly designed/installed kitchen ventilation system and inadequate ventilation rates.

• High noise levels may be present due to the proximity of a space to and adjacent busy road and / or a plant room, insufficient sound insulation and lack of sound absorption materials used on wall and ceiling surfaces. No local controls may be available for an occupant not adjacent to an openable window or window or an adjustable thermostat (in many cases local thermostats may be disabled to prevent excessive adjustment by occupants).

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Pollutants Types

Sick building syndrome (SBS)

• The existence and extent of SBS may be established using questionnaires. Occupants are asked to score their satisfaction level for ambient variables including air temperature, perceived humidity level, local (fresh) air flow, noise, task lighting, glare and odours, and their ability to control some of these values.

Pollutants Types

Sick building syndrome (SBS)

• Analysis is then performed on the data to determine whether conditions are satisfactory for the occupants in each assessed area.

• Results should indicate what modifications might be required to achieve acceptable thermal, lighting and acoustic conditions. In relation to ventilation, this may include increased fresh air flow rates, adjustment of diffusers, more frequent maintenance of ventilation plant and improved occupant access to controls.

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Pollutants Types

External (outdoor) air pollution

• Poor outdoor air quality will have significant impact on indoor air quality. External pollutants include vehicle exhausts, discharges from combustion appliances, industrial process and power station exhausts.

• Fungal spores and pollen from vegetation may also cause air quality problems. Vehicle exhausts include CO, CO2, NOx and SO2, particulates (especially from diesel engines) and VOCs (e.g from petrol and oil).

Pollutants Types

External (outdoor) air pollution

• Ozone is generated by the action of sunlight on nitrous oxides (present in vehicle exhausts).

• Power station release the same pollutants to vehicles, but are usually located in rural or semi-rural areas, so the impact of their pollutants is much reduced.

• In urban areas, traffic is a significant contributor to external pollution, with additional pollutant emissions coming from building exhausts and industrial processes.

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Outdoor Air Quality

Motorists passed a highway toll gate covered by thick haze in Kuala Lumpur, Malaysia, Thursday, Aug. 11, 2005. The ominous haze that has shrouded parts of Southeast Asia this month is just one visible element of a much larger problem that is choking hundreds of thousands to death every year across the region, the World Health Organization said. (AP Photo/Andy Wong)

What Are OA Intake Restrictions?

· Significant contaminated exhaust· Noxious or dangerous exhaust· Chimneys and flues· Truck loading area· Driveway, street· Thoroughfare w/high traffic· Garbage dumpster· Cooling tower

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RNC/NRNC - Air Cool Split Units

• It basically comprises an indoor unit with the evaporator and blower and an outdoor unit with the compressor, condenser coil and fan coupled with refrigeration piping.

• The indoor units is often known as Fan Coil Units ( FCUs )and the outdoor units known as Condensing Units.( C.U.) As a whole, they are known as the Air Cooled Split Units. (ACSUs)

Air Cooled Split Units

Warm air (recirculating)

Cool air

Outdoor air

Fan Coil Unit

Condensing Unit

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Air Cooled Split Units (ACSUs) – Inverter type

Both indoor and outdoor units are housed in

robust casings. The outdoor unit is basically the

same construction for all the various types of

indoor units. The difference lies in the type of

indoor unit. Wall Mounted Cassette

Ceiling Exposed

Floor Standing

Air Cooled Split Units

Many Business Establishments are housed in Small Premises using ACSUs.

Office Restaurant

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ACSUs ( incld. Inverter type ) : Fresh Air Intake ?

The wall mounted, floor standing and under ceiling split system has no provision for intake of outdoor air and/or exhaust of stale room air.

Room air is just filtered and re-circulated .

.

Can you consider this for large buildings?

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Ducted Systems – Introducing OA

• Building-Related Illness (BRI) is a term referring to illness brought on by exposure to the building air, where symptoms of diagnosable illness are identified and can be directly attributed to environmental agents in the air. Eg. of BRI is Legionnaires’ Disease commonly found in aquatic environment.

IAQ Definitions

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CODES and STANDARDS FOR IAQ PERFORMNCE AND THERMAL COMFORT

EQ1: Minimum IAQ Performance• Meet the minimum requirements of ventilation

rate in ASHRAE Standard 62.1:2010 or the local building code whichever is the more stringent.

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ASHRAE STD 62.1-2010 Ventilation For Acceptable For Indoor Air Quality

Ventilation is the key to Sustainable IAQ and ASHRAE Std 62.1 is the most widely recognisedStandard Internationally by most countries and HVAC Engineers in the world.

EQ1: Minimum IAQ Performance

MS 1525:2007

8. Air Conditioning and Mechanical Ventilation (ACMV) System

Indoor Design ConditionRecommended Design DB Temperature 23 - 26ºC (73.4 – 78.8°F )Minimum DB Temperature 22ºCRecommended Design RH 55% - 70%Recommended Air Movement 0.15 m/s – 0.50m/sMaximum Air Movement 0.7 m/s

Outdoor Design ConditionsRecommended Outdoor Design 33.3ºC / 27.2ºC

Conditions DB / WB ( 92°F/ 81°F )

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Industry Code of Practice on Indoor Air Quality 2010DOSH Malaysia* Ministry of Human ResourcesTable 1: List of Indoor Air Contaminants and the Maximum Limits

Acceptable Range for Specific Physical Parameters – 2010

Parameter Acceptable range

(a) Air temperature

(b) Relative humidity

(c) Air movement

23.0 – 26.0 ºC

40 – 70%

0.15 – 0.50

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List of Indoor Air Contaminants and acceptable limi ts

Indoor Air Contaminants Eight-hours time-weighted av erage airborne concentration

ppm mg/m³ cfu/m³

Chemical contaminants(a) Carbon dioxide(b) Carbon monoxide(c) Formaldehyde(d) Ozone(e) Respirable particulates(f) Total volatile organic compounds

(TVOC)

C1000100.1

0.05-3

----

0.15-

------

Biological contaminants(a) Total bacterial counts(b) Total fungal counts

--

--

5001000

ASHRAE Standard 55-2010

Specifies conditions

likely to be

thermally

acceptable to at

least 80% of the

adult occupants in a

space

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Specifies Conditions likely to be thermally acceptable to at least 80% of the adult occupants in a space

Indoor Environmental Quality – Thermal Comfort (EQ6)Design to ASHRAE 55-2010 : Thermal Environmental Conditions for Human Occupancy in conjunction with relevant localised parameters as listed in MS 1525:2007

6 Primary factors that must be addressed when defining conditions for thermal comfort are:

1.) Metabolic rate2.) Clothing insulation3.) Air temperature4.) Radiant temperature5.) Air speed6.) Humidity

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1.) Factors affecting comfort and Indoor Air Quality (IAQ)

• Space Temperature• Relative Humidity• Air Velocity• Noise and Acoustic Level• Ventilation - Supply of Acceptable Air & removal of

Unacceptable Air• Lack of Maintenance of ACMV ( HVAC ) system

( eg. Filters not cleaned or replace regularly )

What are the IAQ Problems in Buildings?

• IAQ during design and construction• Lack of Commissioning• Moisture in Building Assemblies• Poor Outdoor Air Quality• Moisture and Dirt in Ventilation• Indoor Contaminant Sources• Contaminants from Indoor Equipment and Activities• Inadequate Ventilation Rates• Ineffective Filtration and Air Cleaning

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*EQ1: Minimum IAQ Performance

• Meet the minimum requirements of ventilation rate in ASHRAE Standard 62.1:2007 or the local building code whichever is the more stringent.

Minimum IAQ Performance

MS 1525:2007Section 8.1.4 Ventilation

Outdoor Air-Ventilation Rates should comply with Third Schedule (By Law 41) Article 12 (1) of Uniform Building By Laws, 1984 ( UBBL )

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Building code requirements

Extract from Third Schedule (By-law 41)

ASHRAE Comfort Zone

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ASHRAE STD 62.1-2010 Ventilation For Acceptable For Indoor Air Quality

Ventilation is the key to Sustainable IAQ and ASHRAE Std 62.1 is the Leading Standard adopted by most Local Authorities and HVAC Engineers in the world.

EQ1: Minimum IAQ Performance

1.) Ventilation Rate Procedure ( VRP )

2.) Indoor Air Quality Procedure ( IAQ )

3.) Natural Ventilation –permitted to be used in conjunction with MechanicalVentilation.

ASHRAE Std 62.1-2010 – Ventilation For Acceptable Indoor Air Quality

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1.) Ventilation Rate Procedure ( VRP ) –is a prescriptive procedure with a table of minimum required outdoor airflow

rates per occupant for a variety of non-

residential occupancies.

The airflow rate per square foot of building floor area is based-

on the design occupancy density and the required flow rate per person,

adjusted to reflect the air distribution system used.

Acceptable Indoor Air Quality is defined as air in which there are no known Contaminants at harmful Concentrations as determined by Cognizant Authorities and with which a substantial majority ( 80% or more ) of the people exposed do not express dissatisfaction.

1.) Ventilation Rate Procedure ( VRP )Vbz = Rp.Pz + RA.AZ ( PEOPLE + AREA COMPONENT )

Where Vbz = Design outdoor airflow required in the breathing zone of the occupied space or spaces in a zone,i.e the breathing zone outdoor air flow

Az = Zone floor area: the net occupiable floor area of the zone m2 ( ft2)

Pz = zone population: the largest number of people expected to occupy the zone during typical usage.

Rp = outdoor airflow rate required per person as determined from Table 6-1

Ra = outdoor airflow rate required per unit area as determined from Table 6-1

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TABLE 6-1 MINIMUM VENTILATION RATES IN BREATHING ZONE

People Outdoor Area Outdoor Default Values

Occupancy Air Rate Air RateOccupant Density

Combined Outdoor

Category Rp RaAir Rate

cfm/person

L/s person

cfm/ft²

L/s m²

#1000 ft ² cfm/person

L/s personor #100 m ²

Office Buildings COPY

Office Space 5 2.5 0.06 0.3 5 17 8.5

Reception areas 5 2.5 0.06 0.3 30 7 3.5

Hotels, Motels, Resort, Dormitories

Bedroom / living room 5 2.5 0.06 0.3 10 11 5.5

Barracks sleeping areas 5 2.5 0.06 0.3 20 8 4.0

Laundry rooms, central 5 2.5 0.12 0.6 10 17 8.5

Laundry rooms within 5 2.5 0.12 0.6 10 17 8.5dwelling units

Lobbies / pre-function 7.5 3.8 0.06 0.3 30 10 4.8

Multipurpose assembly 5 2.5 0.06 0.3 120 6 2.8

TABLE 6-1 MINIMUM VENTILATION RATES IN BREATHING ZONE

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1.) Example : Ventilation Rate Procedure ( VRP )Vbz = Rp.Pz + Ra.Az

Where Vbz = Design outdoor airflow required

Az = floor area = 1,000 sq. ft. , Pz = population = 5 people (20m2/person )

Rp = outdoor airflow rate required per person as determined from Table 6-1 = 5 cfm/person

Ra = outdoor airflow rate required per unit area as determined from Table 6-1 = 0.06 cfm/ft2

Vbz = Rp.Pz + Ra.Az = 5 x 5 + 0.06 x 1,000= 85 cfm i.e 17cfm/person

ASHRAE Std 62.1-2007 – Ventilation For Acceptable In door Air Qualy

2.) Example : Ventilation Rate Procedure ( VRP )Vbz = Rp.Pz + Ra.Az

Where V bz = Design outdoor airflow required

Az = floor area = 10,000 sq. ft. , P z = population = 100 peopleRp = outdoor airflow rate required per person as deter mined

from Table 6-1 = 5 cfm/personRa = outdoor airflow rate required per unit area as de termined

from Table 6-1 = 0.06 cfm/ft2

Vbz = Rp.Pz + Ra.Az = 5 x 100 + 0.06 x 10,000= 1,100 cfm i.e 11cfm/person

ASHRAE Std 62.1-2007 – Ventilation For Acceptable In door Air Qualy

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Ventilation Rate Procedure ( VRP )Vbz = Rp.Pz + Ra.Az

Where Vbz = Design outdoor airflow required

Eg. 2 – Banks or bank lobbies ( Default Values )Az = floor area = 100 m2 , Pz = population = 15 peopleRp = outdoor airflow rate required per person as determined from

Table 6-1 = 3.8 L/s.personRa = outdoor airflow rate required per unit area as determined

from Table 6-1 = 0.3 L/s.m2

Vbz = Rp.Pz + Ra.Az = 3.8 x 15 + 0.3 x 100= 57 + 30 = 87 L/s = 6.0 L/s.person

ASHRAE Std 62.1-2007 – Ventilation For Acceptable In door Air Quality

MINIMUM VENTILATION RATES IN BREATHING ZONE

People Outdoor Area Outdoor Design Values

OccupancyAir Rate Air Rate Occupant

DensityCombined Outdoor

Category Rp Ra Air Rate

cfm/person

L/s person

cfm/ft²

L/s m²

#1000 ft ² cfm/person

L/s personor #100 m ²

Office Buildings

Office Space 5 2.5 0.06 0.3

10ft2/person10 17 8.5

Banks or Bank lobbies 7.5 3.8 0.06 0.3

50ft2/person

15 12 6.0

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MINIMUM VENTILATION RATES IN BREATHING ZONE

People Outdoor Area Outdoor Design Values

Occupancy Category

Air RateRp

Air Rate Ra

Occupant Density

Combined Outdoor Air Rate

cfm/person

L/s person

cfm/ft ² L/s m ²#1000 ft ² or

#100 m²cfm/

personL/s

person

Hotels, Motels, Resort, Dormitories

Places of religious worship

5 2.5 0.06 0.35ft2/person

2005.3 2.7

Libraries 5 2.5 0.12 0.650ft2/person

2011 5.5

Retail Mall common areas

7.5 3.8 0.06 0.320ft2/person

509 4.5

Lecture Classroom

7.5 3.8 0.06 0.310ft2/person

1008 4.0

Educational Facilities

Computer lab 10 5 0.12 0.620ft2/person

5012.4 6.2

Restaurant Dining rooms

7.5 3.8 0.18 0.910ft2/person

1009.3 4.7

MINIMUM VENTILATION RATES IN BREATHING ZONE

People Outdoor Area Outdoor Design Values

Occupancy Category

Air RateRp

Air Rate Ra

Occupant Density

Combined Outdoor Air Rate

cfm/person

L/s person

cfm/ft ² L/s m ²#1000 ft ² or

#100 m²cfm/

personL/s

person

Hotels, Motels, Resort, DormitoriesLobbies/ prefunction

7.5 3.8 0.06 0.320ft2/person

509 4.5

Multi purpose assembly

5 2.5 0.06 0.36.7ft2/person

1505.4 2.7

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Air Classification and Recirculation

Class 1: Air with low contaminant concentration, low sensory-irritation intensity, and inoffensive odor.

Class 2: Air with moderate contaminant concentration, mild sensory-irritation intensity, or mildly offensive odors. Class 2 air also includes air that is not necessarily harmful or objectionable but that is inappropriate for transfer or recirculation to spaces used for different purposes.

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On a single refrigerant pipe, many indoor units can be connected.

Variable Refrigerant System ( VRS )/Variable Refrigerant Flow ( VRF )

Many Fan Coil Units ( up to 60 units)

Ashrae Malaysia Chapter one day seminar

April 200858

Cassette unit with fan, filter and ducting for outdoor air

Remedial measures- 1.HVAC Specifying engineers

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Ashrae Malaysia Chapter one day seminar

April 200859

Cassette unit with fan, filter and ducting for outdoor air

Remedial measures-1.HVAC Specifying engineers

2.) Indoor Air Quality Procedure ( IAQ ) is a performance – based design approach in which the building and its ventilation system

are designed to maintain the concentrations of specific contaminants at or below certain limits identified during the building design and to achieve the design target level of perceived IAQ acceptability by occupants.

ASHRAE Std 62.1-2007 – Ventilation For Acceptable Indoor Air Quality

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2.) Indoor Air Quality Procedure ( IAQ )

It provides an engineered approach to an acceptabl e IAQ in a building :-

i) identify contaminants of concernii) likely rates of generation and acceptable leve ls of these

contaminantsiii) defining a system and outdoor ventilation rate that together will

maintain the contaminants concentration below maxim um acceptable level

Air Purification to remove some or all of the conta minants of concern can be part of the system

ASHRAE Std 62.1-2007 – Ventilation For Acceptable Indoor Air Quality

• ASHRAE Standard 62.1-2007, “Ventilation for Acceptable Indoor Air Quality,”specifies minimum ventilation rates and indoor air quality that will be acceptable to the human occupants of a building.– Considers chemical, physical, and biological contam inants .

Table 6-1 Minimum Ventilation Rates in Breathing Zone

(PEOPLE COMPONENT ONLY )

Rp , Flow rate per person or per unit area (ASHRAE 62.1 -2010) e.g. Office space – 5cfm/person Mall & supermarket – 7.5 cfm/personRestaurant & Café – 7.5 cfm/person Lecture hall – 7.5 Cfm/personGames arcade / Casino – 7.5 Cfm/personComputer & Science Lab – 10 Cfm/personDisco & Aerobics room – 20 Cfm/person

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COST OF USING HIGH FA

At Ambient of 92°F DB/81° FWB (33.3°C/ 27.2°C)

174.3 Cfm ( 300 M³/Hr) of FA

Requires 1 Ton ( 3.517KW ) of AC Load

High use of Fresh Air Results in

High Capital Cost

High Operating Cost (Energy & Water Cost)

64

ASHRAE STANDARDS 62

Ventilation for Acceptable Indoor

Air Quality

LOCATION

OA REQUIRMENTS FOR

VENTILATION

CFM/Person

(62-1989,1999 & 2001)

MIN.VENTILATION

RATES IN

BREATHING ZONE

(62.1-2004 & 2007)

OFFICE SPACE

CFM/PERSON

20

CFM/Person

5

CONFERENCE ROOM

CFM/PERSON

20

CFM/Person

5

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ASHRAE STANDARDS 62.1

Ventilation for Acceptable Indoor Air Quality

LOCATION

OA REQUIRMENTS FOR

VENTILATION

CFM/Person

(62-1989,1999 & 2001)

MIN.VENTILATION

RATES IN

BREATHING ZONE

(62.1-2004,2007 &

2010 )

AUDITORIUM

CFM/PERSON

20

CFM/Person

5 ( People Component)

CLASS ROOM

CFM/PERSON

20

CFM/Person

7.5

(People Component)

66

CALCULATION FOR

ENERGY SAVINGS WITH

REDUCTION OF

OUTDOOR AIR

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67

ASHRAE 62

2001 2010(Cfm/person) (Cfm/person)

OFFICE 20 5 (15)

68

DB WB ENTHALPY

°F °F Btu/lb of dry air

OUTDOOR AIR 92 81 44.78

DESIGN TEMP. 75 64 29.31

15.47

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69

FOR AN OFFICE WITH 200 PERSONS

Savings = 4.45 x CFM x ∆ Enthaply

= 4.45 x (200 x 15) x 15.47

= 17.2 tons (60.5kw)

70

No of People Savings in Chiller Tonnage

100 8.6 ton (30.3KW)

200 17.2 ton (60.5KW)

500 43.0 ton (151.3KW)

1,000 86.1 ton (302.6KW)

2,000 172.1 ton (605.3KW)

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CO2 Monitoring and Demand Control Ventilation ( EQ3)

Question: How could we ventilate the space more efficiently?Answers: Measure Ventilation In The Space Like Temperature

Vary Ventilation Based On Occupancy

Zone Control Ventilation With CO2

Ventilation Is Fixed

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The effect of CO2

on man

0,10%0,10%

0,50%0,50%

1,50%1,50%

3,0%3,0%

8,0%8,0%

Main alarmMain alarm

Pre alarmPre alarm

Fresh airFresh air0,04%0,04%

Convulsions, immediate paralysis and deathConvulsions, immediate paralysis and death

Muscular pain, unconsciousness, convulsions and risk of deathMuscular pain, unconsciousness, convulsions and risk of death

Shortness of breath and increased heart frequencyShortness of breath and increased heart frequency

Hygienic limit valueHygienic limit value

Recommended indoor limit valueRecommended indoor limit value

Carbon Dioxide and DCV. Humans are the main indoor source of CO2.• Indoor carbon dioxide concentrations can be

used to indicate specific and limited aspects of indoor air quality but are not an overall indicator of the quality of indoor air.

• Demand Control Ventilation adjusts ventilation air based on the number of occupants and the ventilation demands that the occupants create.

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Carbon Dioxide and DCV (2)CO2-based DCV has the most energy savings potential in buildings where occupancy fluctuates & when ventilation is over designed.– Office buildings, government

facilities, retail stores and shopping malls, airports, theaters, auditoriums, conference or lecture halls, entertainment areas are good candidates for DCV

CO2 Demand Controlled Ventilation

Assuming a Conference room with

Max. capacity of = 200 people

If Designed Ventilation rate = 7 l/s/ person

The Amount of ventilation required = 1,400 l/s

Now if the Conference room is not fully occupied, say with

No. of People = 70

If Ventilation rate is maintained at 7 l/s/ person

Amount of ventilation = 490 l/s

Examples:

DCV uses CO2 measurement to indirectly determine level of occupancy and thus ventilation

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Typical Installation – AHU Room

AHU

AHU Room

Return Air

Supply Air

Fresh Air

Fresh air damper

Damper Actuator

CO2 sensor

Typical Installation – AHU Room

AHU

AHU Room

Return Air

Supply Air

Fresh Air

Fresh air damper

Damper Actuator

CO2 sensor

Return Air

CO2 sensor PLC

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Carbon Dioxide (CO2) Sensors/Controllers

Wall Mount Application Duct Mount Application

Great potential for Energy savings when:i.) the space has less than maximum occupancyii.) the space has variable occupancy patterniii.) the ventilation is over designed

Sensors are recommended to be verified every 3 years

G+G0

I0

G+G0

I0

G+G0

I0

G+G0

I0

G+G0

I0

R

500nΩ

Variable Speed Drive

CO2

sensor

CO2sensor

CO2sensor

CO2sensor

CO2sensor

4 – 20 mA + 24VCom -

FAN

3ph Supply

n = # of sensors

R = terminating

resistor

Averaging CO2 Sensor Monitoring & Control using VSD

2-10 V input

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• All ventilation air filters will be changed after the flush-out

• Pressure sensor to detect filter blockage

• Purging to eliminate bad odors and improve air quality especially for building space that does not have adequate openable windows

• Ventilation of the encapsulation, hood or extraction type should be provided so that the spread of contaminants is prevented

• Building materials and surface finishes should not contain any substances that emit chemicals, bacteria or fungi

IAQ Before and During Occupancy

26th March 2013

By: Ir. Ng Yong Kong, (email : nyk@nyk.com.my

h/p no. +6012- 201 9319 ) and others.

THANK YOU