indoor air quality (eng) - oshc · 40 indoor air quality for printing plants tables table 3.1 :...

39

OSH Research Report

Contents

Preface 41

Acknowledgements 42

Abbreviations 43

1. Introduction 44

1.1 What is IAQ? 44

1.2 Existing IAQ Guidance Notes 44

1.3 Need for Printing Plant IAQ Guidelines 45

1.4 Objectives 45

1.5 Scope 45

2. Unique Environment in Printing Plants 46

3. Indoor Air Pollutants in Printing Plants 48

3.1 Common Pollutants Found in Indoor Environment 48

3.2 Gaseous Pollutants in Printing Plants 49

3.2.1 Ammonia 50

3.2.2 Isopropyl Alcohol 50

3.2.3 Ethyl Benzene, Toluene and Xylene 51

3.2.4 White Gasoline 53

3.3 Particulate Pollutants in Printing Plants 53

3.3.1 Paper Dust and Starch Powder 54

3.3.2 Ink Mist 55

3.3.3 Carbon Black 55

4. Engineering Control and Mitigation 56

4.1 Mechanical Ventilation 56

4.2 Filtration 57

4.3 Adsorption Air Cleaning 58

4.4 Segregation 58

4.5 Differential Pressure Control 59

4.6 Directional Airflow Control 60

4.7 Local Exhaust Ventilation 61

4.8 Source Control 61

5. Best Practices of Work 62

6. Management of Programme 64

Appendix I Printing Indoor Air Quality (IAQ) Questionnaire 66

Appendix II IAQ Checklist 72

Appendix III Data Sheet for Short-Term IAQ Sampling 75

References 76

○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○

○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○

○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○

○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○

○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○

○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○

○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○

○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○

○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○

○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○

40

Indoor Air Quality for Printing Plants

Tables

Table 3.1 : Exposure limits of indoor air pollutants commonly found in officesand public places 48

Table 3.2 : 8-hour occupational exposure limits of gaseous pollutants 49

Table 3.3 : Active sampling methods for ammonia 50

Table 3.4 : Active sampling methods for isopropyl alcohol 51

Table 3.5 : Active sampling methods for ethyl benzene 51

Table 3.6 : Active sampling methods for toluene 52

Table 3.7 : Active sampling methods for xylene 52

Table 3.8 : Active sampling method for white gasoline 53

Table 3.9 : 8-hour occupational exposure limits of particulate pollutants 53

Table 3.10 : Sampling methods for paper dust and starch (total dust) 54

Table 3.11 : Sampling methods for paper dust and starch (respirable fraction) 54

Table 3.12 : Sampling method for ink mist 55

Table 3.13 : Sampling methods for carbon black 55

Table 4.1 : Ventilation requirements in printing plant 57

Table 4.2 : Filters used in printing plant 58

Table 4.3 : Differential pressure control in printing plant 60

Table 5.1 : Less harmful chemical or process for substitution 62

Table 5.2 : Automatic mechanical devices for handling of chemicals 62

Figures

Figure 2.1 : Commercial offset lithographic printing 46

Figure 4.1 : Ventilation requirements in printing plant 56

Figure 4.2 : Filtration 57

Figure 4.3 : Segregation of facilities in printing plant 59

Figure 4.4 : Differential pressure control in pre-press room 59

Figure 4.5 : Directional airflow in pressroom 60

Figure 4.6 : Local exhaust ventilation 61

Figure 5.1 : Proper position of worker with respect to contaminant sourceand airflow direction 63

Figure 6.1 : Organisational structure of IAQ management team 64

41

OSH Research Report

Preface

This report attempts to provide a guidance to facilitate the control and management of indoor

air quality in printing plants so as to maintain a safe and healthy working environment. The

indoor air pollution concerns, such as sources of contaminants, adverse health effects, and

exposure limits, are discussed in this report. Effective engineering control and mitigation

measures are recommended. The primary group of audience of this report includes engineers,

employers, workers, and administrative staff who strive to manage and run their printing

plants with good indoor air quality.

42


Acknowledgements

This report is one of the deliverables of the research project entitled Indoor Air Quality Control and

Mitigation Measures for Printing Plants which is fully supported by a grant from the Occupational

Safety and Health Council (Research Grant No. CM/4R/2002-02). The research project is undertaken

jointly by Dr Michael K H Leung, Dr Chun-ho Liu, Department of Mechanical Engineering, the

University of Hong Kong and Dr Alan H S Chan, Department of Manufacturing Engineering and

Engineering Management, City University of Hong Kong. The investigators would like to thank all

individuals who have contributed to the implementation of the project and the preparation of this

report. Special thanks go to the following for their tremendous support:

Mr. Dennis Leung, Mountain Arts Screen Printing Co.

Mr. Philip Leung, Printing Unit, the University of Hong Kong

Mr. John K.F. Ng, Fortune Printing International Limited

Mr. Takeaki Ogino, Toppan Printing Co. (HK) Ltd.

Ms. Sin Wai Han, Catalles, Paramount Printing Company Limited and Apple Daily

Mr. Sun Man Ting, Jansun Printing Co. Ltd.

Mr. Willie Tam, Kin Kwok Printing Press Ltd.

Ms. Wai, Elegance Printing & Book Binding Co. Ltd.

Mr. Paul Yuen, Reprographic Section, City University of Hong Kong Press

Our research team members:

Mr. Oliver K.Y. Chau, Student Research Assistant, The University of Hong Kong

Mr. Keith Y.K. Chung, Student Research Assistant, The City University of Hong Kong

43

OSH Research Report

Abbreviations

ACGIH American Conference of Governmental Industrial Hygienists

AHU Air-handling Unit

ASHRAE American Society of Heating, Refrigerating and Air-Conditioning Engineers, Inc.

EPA U.S. Environmental Protection Agency

EPD Environmental Protection Department, Hong Kong

FID Flame Ionization Detector

IAQMG Indoor Air Quality Management Group, Hong Kong

HVAC Heating, ventilation, and air-conditioning

IAQ Indoor Air Quality

LPG Liquefied Petroleum Gas

MSDS Material Safety Data Sheet

NIOSH U.S. National Institute for Occupational Safety and Health

OEL Occupational Exposure Limit

OSHA U.S. Occupational Safety and Health Administration

RSP Respirable Suspended Particulates

TVOC Total Volatile Organic Compounds

USEPA/NAAQS U.S. Environmental Protection Agency/National Ambient Air Quality Standards

WHO World Health Organization

NOHSC National Occupational Health and Safety Commission, Australia

OSHS Occupational Safety and Health Service, New Zealand

VOC Volatile Organic Compounds

Units

cfm Cubic feet per minute

cfu Colony forming units

pCi pico-curies

ppm Parts per million by volume

ppb Parts per billion by volume

44


1. Introduction

1.1 What is IAQ?

The indoor air quality (IAQ) of an indoor environment can be reflected by the degree of satisfaction

of the occupants. Alternatively, in order to facilitate effective management, IAQ is commonly

quantified by more objective measurements combining the concentration of pollutants and thermal

conditions. There are various types of indoor air pollutants found in buildings, namely, inorganic

gases, volatile organic compounds (VOC), particulate matters, airborne micro-organisms, and radon.

Without proper control and management, poor IAQ may cause sick building syndrome (SBS). The

symptoms of SBS include headaches, dizziness, fatigue, irritations of eyes and skin, and so on. The

SBS symptoms disappear soon after the victim leaves the building. Although SBS is neither life-

threatening nor permanently damaging, it may seriously affect our comfort and productivity. Worse

IAQ will lead to building related illnesses (BRI) which are clinically diagnosed illnesses, such as

hypersensitivity pneumonitis, Legionnaires’ disease, cancer, etc. The IAQ problems cause considerable

threat and concern to the community.

In 1995, the Environmental Protection Department (EPD) of Hong Kong commissioned a study to

assess the IAQ in office premises and other selected public places (EHS 1997). The questionnaire

survey showed that 32% of the respondents were not satisfied with the IAQ in their workplace.

The study also concluded that the estimated annual medical costs and productivity losses due to

poor IAQ amounted to economic losses of HK$12.2 billion, which was about 1% of the gross domestic

product (GDP) in Hong Kong.

1.2 Existing IAQ Guidance Notes

In response to the abovementioned substantial losses, the Indoor Air Quality Management Group

(IAQMG) of the Government of Hong Kong Special Administrative Region (HKSAR) issued the first

draft of Guidance Notes for the Management of Indoor Air Quality in Offices and Public Places in

1999 and later revised it to the final draft in 2003 (IAQMG 2003). In that Guidance Note, the

background information and practical guidelines for control and management of IAQ are discussed.

It sets out IAQ objectives and assesses the IAQ based on 12 parameters which include :

1. carbon dioxide (CO2)

2. carbon monoxide (CO)

3. respirable suspended particulates (RSP)

4. nitrogen dioxide (NO2)

5. ozone (O3)

6. formaldehyde (HCHO)

7. total volatile organic compounds (TVOC)

8. radon

9. airborne bacteria

10. room temperature

11. relative humidity, and

12. air movement

45

OSH Research Report

1.3 Need for Printing Plant IAQ Guidelines

The existing IAQ Guidance Notes (IAQMG, 2003), which are intended for offices and public places

where no significant amount of chemicals are used in the vicnity, are not adequate for applying to

printing plants. It is because the unique processes and operations of printing facilities cause IAQ

problems very different from those commonly encountered in offices and public places. The HKSAR

Labour Department has published the Code of Practice on Control of Air Impurities (Chemical

Substances) in the Workplace (Occupational Safety and Health Branch, HKSAR Labour Department

2002). The Code of Practice is a useful reference as it provides the occupational exposure limits of

most industrial chemical substances, including those frequently used in the printing industry.

Moreover, the HKSAR Labour Department has issued the booklet The Protection of Workers’ Health

Series – Solvent (Occupational Safety and Health Branch, HKSAR Labour Department 2000) to provide

practical guidance for the control of the major airborne hazard in the trade. Still, both books lack

in provision of engineering methods for effect of control of the emissions.

1.4 Objectives

The main purpose of this report is to provide useful information to facilitate the control and

management of IAQ to better safeguard the health of workers in printing plants. All information

is based on thorough reviews of relevant references and IAQ assessments of various printing plants.

The report contains the following contents :

1. Sources, adverse health effects and exposure limits of indoor air pollutants of considerable

concern for the printing industry

2. Effective engineering control and mitigation measures

3. Management programme suitable for typical organizational structure of printing companies.

1.5 Scope

This report is written for all, whose works directly or indirectly involve IAQ control and management

in printing plants. The target audiences include the employers, workers, engineers, occupational

health officers, administrative staff and so on. Other professionals working closely with the printing

industry, such as architects, environmental officers and engineering consultants, will also find this

report useful.

46


2. Unique Environment in Printing Plants

Printing is one of the biggest industries in Hong Kong. There are about 45,000 employees. Most

printing companies in Hong Kong are small-scale companies. The average number of employees

per company is 9. A wide range of printing services are available, such as business cards, posters,

books, newspapers, magazines and others. In Hong Kong, offset lithography is the most popular

printing method while other methods include rotogravure, flexographic, letterpress, screen and

plateless types. The major work processes and materials involved in commercial offset lithographic

printing are shown in Figure 1.

Figure 2.1 Commercial offset lithographic printing

47

OSH Research Report

The major sources of indoor air pollutants in printing plants are the uses of solvents, inks, fountain

solutions and cleaning agents. Xylene, ketones and alcohols are common VOC vapours found. The

chemical composition depends on the printing method and substrate used. In offset lithographic

printing, the inks used in sheet-fed presses are dried by oxidative polymerization. Inks used in non-

heat-set web presses are dried by absorption onto the substrate. The amount of VOC emissions

from sheet-fed and non-heat-set web presses is insignificant. However, heat-set presses, in which

the inks are dried by evaporating aliphatic ink oils, emit considerable VOC. Hence, local exhaust

ventilation, catalytic and thermal incineration are usually implemented to mitigate the pollution

problems. Other printing processes and operations that may cause serious VOC emissions include

proofing, ink mixing, cleaning, binding, laminating and storage of chemicals.

There are also special airborne particulate pollutants found in the printing plants. The paper dust

generated in paper folding and cutting processes can be suspended in the air. The starch powder

used to separate printed paper sheets is also an airborne particulate pollutant. Ink, apart of its

presence in a form of vapour, can be found in a form of droplets suspended in the air. All of the

above particulate pollutants are known to cause occupational health problems.

The use of gasoline- and LPG-powered trolleys and fork lifts for in-plant transportation is one of

the sources of combustion gases accumulating in the indoor environment. Combustion of fuels

generates carbon dioxide and nitrogen oxides. Any incomplete combustion produces carbon

monoxide and unburned hydrocarbons. Carbon monoxide is of particular concern as it is a poisonous

gas that may cause permanent neurological damage and even death.

48


3. Indoor Air Pollutants in Printing Plants

3.1 Common Pollutants Found in Indoor Environment

In a general work environment, the common indoor air pollutants emitted from furniture, office

equipment, occupants etc. are described in the IAQ Guidance Notes (IAQMG 2003). The exposure limits

of these pollutants adopted by different professional organizations are summarized in Table 3.1.

Tab

le 3

.1 E

xpo

sure

lim

its

of

ind

oo

r ai

r p

ollu

tan

ts c

om

mo

nly

fo

un

d in

of f

ices

an

d p

ub

lic p

lace

s

Carb

on D

ioxi

de(C

O2)

ppm

800

(8 h

r, E)

*1,

000

(8 h

r, G)

5,00

0 (8

hr)

30,0

00 (1

5 m

in)

1,00

0

- -

5,00

0 (8

hr)

30,0

00 (1

hr)

5,00

0 (8

hr)

30,0

00 (1

5 m

in)

5,00

0 (8

hr)

30,0

00 (1

5 m

in)

5,00

09,

000

(15

min

)

5,00

0 (8

hr)

30,0

00 (1

5 m

in)

5,00

0 (8

hr)

30,0

00 (1

5 m

in)

Nitr

ogen

Dio

xide

(NO

2)

ppm

0.02

(8 h

r, E)

0.08

(8 h

r, G)

3 (8

hr)

5 (1

5 m

in)

0.05 -

0.08

(24

hr)

0.2

(1 h

r)1

(15

min

)

1 (1

5 m

in)

1 (1

5 m

in)

3 (8

hr)

5 (1

5 m

in)

5

3 (8

hr)

5 (1

5 m

in)

3 (8

hr)

5 (1

5 m

in)

Carb

on M

onox

ide

(CO

)

ppm

1.7

(8 h

r, E)

8.7

(8 h

r, G)

25 (8

hr)

-

9 (8

hr)

35 (1

hr)

8.6

(8 h

r)25

(1 h

r)50

(30

min

)86

(15

min

)

50 (8

hr)

35 (8

hr)

25 (8

hr)

30

30 (8

hr)

50 (1

hr)

100

(30

min

)20

0 (1

5 m

in)

Ozo

ne(O

3)

ppm

0.03

(8 h

r, E)

0.06

(8 h

r, G)

0.05

(8hr

; hea

vy w

ork)

0.08

(8 h

r; m

oder

ate w

ork)

0.1

(8 h

r; lig

ht w

ork)

0.2

(� 2

hou

rs)

0.05

(1 h

r)

0.08

(8 h

r)0.

12 (1

hr)

0.08

(8 h

r)0.

1 (1

hr)

0.1

(8 h

r)0.

3 (1

5 m

in)

0.1

(15

min

)

0.05

(8 h

r)0.

2 (1

5 m

in)

0.1

0.1

(cei

ling)

0.1

(cei

ling)

Form

alde

hyde

(HCH

O)

ppm

0.02

5 (8

hr,

E)0.

081

(8 h

r, G)

0.3

(Cei

ling)

0.06

5 (c

eilin

g)

0.1

0.08

1 (3

0 m

in)

0.75

(8 h

r)2

(15

min

)

0.01

6 (8

hr)

0.1

(15

min

)

0.3

(cei

ling)

0.3

1 (8

hr)

2 (1

5 m

in)

1 (c

eilin

g)

HKSA

R/IA

QM

G a

HKSA

R/La

bour

Depa

rtm

ent b

Chin

a c

ASHR

AE d

USEP

A/NA

AQS

e

WHO

/Eur

ope

f

OSH

A g

NIO

SH R

EL h

ACGI

H i

MAK

(Ger

man

y) d

NOHS

C (A

ustr

alia

) j

OSH

S(N

ew Z

eala

nd) k

Tota

l Vol

atile

Org

anic

Com

poun

ds(T

VOC)

�g/

m3

200

(8 h

r, E)

600

(8 h

r, G)

- - - - - - - - -

Resp

irabl

e Su

spen

ded

Part

icula

tes

RSP

(PM

10)✝

�g/

m3

20 (8

hr,

E)18

0 (8

hr,

G)

3 (8

hr)

-

150

(24

hr)

- - - - - - -

Rado

n

pCi/L

4 (8

hr,

E)5.

4 (8

hr,

G)

- - - - - - - - -

No

te: P

leas

e re

fer

to t

he

Ref

eren

ces

for

full

cita

tio

ns.

a. H

KSA

R/IA

QM

G 2

003

b. H

KSA

R L

abo

ur

Dep

artm

ent

c. �� !"#$$%&'()*

2000

d. A

SHR

AE

2001

e. U

SEPA

/NA

AQ

S 20

01f.

WH

O 1

999

g. O

SHA

200

2h

. NIO

SH 1

988

i. A

CG

IH 2

001

j. N

OH

SC 1

995

k. O

SHS

2002

* E

and

G d

eno

te “

Exce

llen

t” c

lass

an

d “

Go

od

” cl

ass,

res

pec

tive

ly.

✝ Par

ticu

late

s (P

M10

) re

fer

to s

usp

end

ed p

arti

cles

hav

ing

dia

met

ers

of

10 (

m o

r le

ss.

49

OSH Research Report

3.2 Gaseous Pollutants in Printing Plants

In printing plants, there are more chemical vapours present in the indoor environment causing

occupational health risk. These air contaminants and recommended exposure limits are summarized

in Table 3.2. In the following subsections, particularly important contaminants are discussed in

more details, including the sources, adverse health effects and measurement methods.

Table 3.2 8-hour occupational exposure limits of gaseous pollutants

Pollutant HKSAR Labour Department a NIOSH RELb OSHA PELc

ppm ppm ppm

Ammonia 25 25 50

Benzene 0.5 0.1 1

Carbon dioxide 5,000 5,000 5,000

Carbon monoxide 25 35 50

Chlorobenzene 10 - 75

Chloroform 10 - 50

Chloromethane (methyl chloride) 50 - 100

p-Dichlorobenzene 10 - 75

Dichlorodifluoromethane 1,000 1,000 1,000

cis-1,2-Dichloroethene 10 1 50

1,2-Dichloroethane 10 1 100

Ethylbenzene 100 100 100

Formaldehyde 0.3 0.016 0.75

Methylene chloride 50 - 25

Nitrogen dioxide 3 1 -

Ozone 0.1 0.1 0.1

Styrene 20 50 100

1,1,2,2-Tetracholoroethane 1 1 5

Toluene 50 100 200

1,1,1-Trichloroethane 350 - 350

1,2,4-Trimethylbenzene 25 25 -

1,3,5-Trimethylbenzene 25 25 -

m-Xylene 100 100 100

o-Xylene 100 100 100

p-Xylene 100 100 100

a. HKSAR Labour Department (2002)

b. NIOSH REL - recommended exposure limits (NIOSH 2003)

c. OSHA PEL - permissible exposure limits (OSHA 1991)

50


3.2.1 Ammonia

Sources and health effects

Ammonia (NH3) is commonly used in plate making processes for developing solution in offset

lithographic printing. Ammonia gas is colourless with a pungent, suffocating odour. It is also a

flammable gas. Over exposure to ammonia causes irritation of eyes and throat, dyspnea (breathing

difficulty), wheezing, chest pain and pulmonary edema.

Measurement methods

Ammonia can be measured by active sampling methods in which air samples are collected for

laboratory analysis. These methods are summarized in Table 3.3.

Table 3.3 Active sampling methods for ammonia

Method Description

• Sampler: solid sorbent tube (sulfuric acid-treated silica gel)

NIOSH 6015a • Technique: visible absorption spectrophotometry using indophenol blue dye

• Working range: 0.2 to 400 ppm (0.15 to 300 mg/m3) for a 10-litre air sample

• Sampler: solid sorbent tube (sulfuric acid-treated silica gel)

NIOSH 6016a • Technique: ion chromatography conductivity detection

• Working range: 24 to 98 ppm (17 to 68 mg/m3) for a 30-litre sample

• Sampler: glass tube containing carbon beads impregnated with sulfuric acid (CISA)

OSHA ID188b • Technique: samples are analyzed by ion chromatography after resorption in deionised water

• Validation range: 30.7 to 101.8 ppm

Note: please refer to the References for full citations.

a. NIOSH 1994

b. OSHA 2001

3.2.2 Isopropyl Alcohol


Isopropyl alcohol (C3H8O) is an aqueous solution commonly used to dampen the nonimage area on

the plate. It is also known as fountain or dampen solution in offset lithographic printing. The

fountain solution commonly contains 15 - 30% alcohol. The adverse health effects due to exposure

to isopropyl alcohol include irritation of eyes, nose and throat, drowsiness, dizziness and headache.

51

OSH Research Report

Measurement methods

Isopropyl alcohol can be measured by active sampling methods as summarized in Table 3.4.

Table 3.4 Active sampling methods for isopropyl alcohol

Method Description

• Sampler: solid sorbent tube (coconut shell charcoal)

NIOSH 1400a • Technique: gas chromatography, FID

• Working range: 4 to 400 ppm (10 to 1,000 mg/m3) for a 3-litre air sample

OSHA ID109b• Sampler: anasorb747 tube containing adsorbent

• Technique: gas chromatography, FID


a. NIOSH 1994

b. OSHA 2001

3.2.3 Ethyl benzene, Toluene and Xylene


Organic solvents, such as ethyl benzene (CH3CH2C6H5), toluene (C6H5CH3) and xylene (C6H4(CH3)2),

are mainly used as the volatile component of ink. Toluene has a sweet, pungent and benzene-like

odour, while ethyl benzene and xylene have an aromatic odour. Excessive exposure may damage

the central nervous system, eyes, skin, respiratory system, liver and kidneys.

Measurement methods

The vapour content of ethyl benzene, toluene and xylene, can be measured by portable direct-

reading instrument or gas chromatography. More details can be found in Tables 3.5, 3.6, and 3.7.

Table 3.5 Sampling methods for ethyl benzene

Method Description



• Working range: 222 to 884 mg/m3 for a 1-litre air sample

OSHA 7b• Sampler: charcoal tubes (coconut shell charcoal)


OSHA 1002b• Sampler: charcoal tubes (coconut shell charcoal)



a. NIOSH 1994

b. OSHA 2001

52


Table 3.6 Sampling methods for toluene

Method Description

• Sampler: solid sorbent tube (coconut shell charcoal)NIOSH 1500a • Technique: gas chromatography, FID

• Working range: 548 to 2,190 mg/m3 for a 2- to 8-litre air sample

• Sampler: solid sorbent tube (coconut shell charcoal)NIOSH 1501a • Technique: gas chromatography, FID

• Working range: 548 to 2,190 mg/m3 for a 1-litre air sample

• Sampler: portable direct-reading instrument

NIOSH 3800a• Technique: extractive Fourier transform infrared (FTIR) spectrometry• Working range and the limit of detection: may vary from laboratory to laboratory,

analyst to analyst, instrument to instrument,and day to day

• Sampler: diffusive sampler (activated carbon)NIOSH 4000a • Technique: gas chromatography (FID)

• Working range: 13 to 660 ppm (50 to 2,500 mg/m3) for a 4-hour sample

• Sampler: adsorbent tube, Anasorb® 747 tubes, or diffusive samplersOSHA 111b • Technique: gas chromatography (FID)

• Working range: vary from sampling methods


a. NIOSH 1994

b. OSHA 2001

Table 3.7 Sampling methods for xylene

Method Description




• Sampler: portable direct-reading instrument

NIOSH 3800a• Technique: extractive Fourier transform infrared (FTIR) spectrometry

• Working range and the limit of detection: may vary from laboratory to laboratory,

analyst to analyst, instrument to instrument, and day to day

OSHA 1002b

• Sampler: active sampling through coconut shell charcoal sampling tubes or passive

samplers SKC 575-002

• Techniques: gas chromatography, FID


a. NIOSH 1994

b. OSHA 2001

53

OSH Research Report

3.2.4 White Gasoline


White gasoline, also known as petrol, is used in a variety of applications, such as fuel, metal

degreasing, cleaning of printing plates and rubber blankets. It is a complex mixture of volatile

hydrocarbons containing paraffins, cycloparaffins and aromatics. The major health effects are

irritation of eyes, skin, mucous membrane; dermatitis; headache, lassitude, blurred vision, dizziness,

slurred speech, confusion and convulsion.

Measurement method

The measurement method of white oil is presented in Table 3.8.

Table 3.8 Sampling method for white oil

Method Description

OSHA PV2028a

• Sampler: charcoal tube

• Technique: samples are desorbed with carbon disulfide and analyzed by gas

chromatography using a flame ionization detector


a. OSHA (2001)

3.3 Particulate Pollutants in Printing Plants

Apart from gaseous pollutants, there are important particulate pollutants in printing plants. These

pollutants and their 8-hour occupational exposure limits are presented in Table 3.9.

Table 3.9 8-hour occupational exposure limits of particulate pollutants

Pollutant HKSAR Labour Departmenta NIOSH RELb OSHA PELc

mg/m3 mg/m3 mg/m3

Carbon black 3.5 3.5 3.5

Cellulose (paper fiber/dust) 10 5 5 (respirable)

15 (total)

Ink mist d 5 5 5

Respirable particulate (insoluble) 3 - -

Starch (respirable) 4 5 5

Starch (inhalable) 10 - -

a. HKSAR Labour Department (2002)

b. NIOSH REL - recommended exposure limits (NIOSH 2003)

c. OSHA PEL - permissible exposure limits (OSHA 1991)

d. Exposure limit of oil mist employed

54


OSHA Particulates

“not otherwise regulated”

(total dust)b

3.3.1 Paper Dust and Starch Powder


The fundamental molecular formula of paper dust and starch is (C6H10O5)n. Paper dust is a unique

indoor air pollutant in paper-product-related industry. The dust often generated from paper cutting

can be suspended in the air. Besides, starch powder which is used to separate printed paper sheets

is another airborne particulate pollutant in offset lithographic printing. The symptoms of over

exposure include irritation of eyes, skin and mucous membrane; cough, chest pain; dermatitis;

rhinorrhea (discharge of thin mucus).

Measurement method

Airborne paper dust and starch powder can be measured by portable direct-reading instrument

employing laser-photometer. More detailed measurement methods suggested by NIOSH and OSHA

are tabulated in Tables 3.10 and 3.11.

Table 3.10 Sampling methods for paper dust and starch (total dust)

Method Description

• Sampler: tared polyvinyl chloride 5 �m filter

NIOSH 0500a • Technique: gravimetric


• Sampler: tared low ash polyvinyl chloride (LAPVC) filter 5 �m. Do not use a

cyclone

• Technique: gravimetric


a. NIOSH (1998)

b. OSHA (2004)

Table 3.11 Sampling methods for paper dust and starch (respirable fraction)

Method Description

• Sampler: tared polyvinyl chloride 5 �m filter and 10 mm nylon cyclone

NIOSH 0600a • Technique: gravimetric

• Working range: 0.5 to 10 mg/m3 for a 200-litre air sample

• Sampler: tared low ash polyvinyl chloride (LAPVC) filter 5 �m preceded by

a 10 �m nylon cyclone

• Technique: gravimetric


a. NIOSH (1998)

b. OSHA (2004)

OSHA Particulates

“not otherwise regulated”

(respirable fraction)b

55

OSH Research Report

3.3.2 Ink Mist


Ink mist or ink fly is often encountered in pressrooms. The major sources are ink rollers rotating in

opposite direction and dispersing minute ink droplets ranging from 5 to 10 �m in diameter. The

major substances of ink mist include oil vehicle (usually mineral oil), varnishes, wetting agents,

carbon black and colored pigments. The mineral oil is a complex mixture of aromatic, naphthenic

and straight- or branched-chain paraffinic hydrocarbons. The polynuclear aromatic hydrocarbons

(PAHs) are potential carcinogens. As the cloud of ink droplets is electrostatically charged, local

control by charged suppressors can repel the ink back to the ink rollers to reduce the emission.

Measurement method

The ink mist can be collected by the methods described in Table 3.11. The ink mist content of the

sample collected can be subsequently analyzed by infrared spectrophotometry in accordance with

NIOSH 5026 as described in Table 3.12.

Table 3.12 Sampling method for ink mist

Method Description

• Sampler: membrane filter

NIOSH 5026a • Technique: infrared spectrophotometry



a. NIOSH (1994)

3.3.3 Carbon Black


Carbon black or colored pigment contained in ink can also cause indoor air pollution. As carbon

black absorbs polynuclear aromatic hydrocarbons (PAHs), it becomes a potential carcinogen.

Measurement methods

Carbon black can be measured by filtering and gravimetric methods described in Table 3.13.

Table 3.13 Active sampling methods for carbon black

Method Description

• Sampler: tared 5 mm polyvinyl chloride (PVC) membrane filter

NIOSH 5000a • Technique: Gravimetric (filter weight)

• Working range: 0.5 to 10 mg/m3 for a 200-litre air sample

• Sampler: polyvinyl chloride (PVC) filters

OSHA ID196b • Technique: Gravimetric (filter weight)

• Validation range: 30.7 to 101.8 ppm


a. NIOSH 1994

b. OSHA 2001

56


Although there are many sources of air contaminants in a printing plant, the work environment

can be safe and comfortable if proper engineering control and mitigation measures are implemented.

4.1 Mechanical Ventilation

Mechanical ventilation is an essential IAQ control. Indoor air contaminants are diluted when the

contaminated indoor air is exhausted and clean outdoor air is introduced into the air-conditioned

environment, as illustrated in Figure 4.1. Ventilation can be measured by the volumetric flow rate

of outdoor air. Alternatively, ventilation can be quantified by the number of air changes per hour

(ACH), referring to the number of times a volume of air, equivalent to the space volume, driven

into that space in one hour.

An outdoor air supply of 5 to 10 L/s•m2 (about 6 to 12 ACH) should be adequate for most industrial

facilities (ACGIH 2001). In the production areas of printing plants, it is recommended that the

outdoor air supply should be at least 2.5 L/s •m2 (about 3 ACH) to provide minimal dilution of VOC

generated (ASHRAE 2003). The ventilation in storage and bindery areas should be maintained at

about 0.5 and 1 ACH, respectively. For general-purpose warehouses, the recommended ventilation

should be between 1 and 4 ACH. In the office areas, the outdoor supply air should be at least 10 L/s

per person (ASHRAE 2001). A summary is provided in Table 4.1. More ventilation requirements for

printing plants can be found in ASHRAE Applications Handbook (2003).

Figure 4.1 Mechanical ventilation

4. Engineering Control and Mitigation

57

OSH Research Report

Table 4.1 Ventilation requirements in printing plant

Area Minimum outdoor air intake

General Production Area 5 to 10 L/s • m2 (about 6 to 12 ACH)

Pressroom 2.5 L/s • m2 (about 3 ACH)a

5 ACHb

Pre-Press Room (Film and Plate Developers) 5 ACH

Storage Area 0.5 ACH

Bindery Area 1 ACH

General-Purpose Warehouse 1 to 4 ACH

Office 10 L/s per person

Canteen 10 L/s per person

a. ASHRAE 2003

b. HSE (2004)

4.2 Filtration

Filters can effectively collect particulate contaminants by means of straining (sieving), direct

interception, inertial deposition, diffusion and electrostatic effect. Filters are normally installed

inside air-handling units and fan-coil units. The configuration is shown in Figure 4.2. In printing

plants, the particulate contaminants are mostly starch powder and paper dust suspended in the air.

The proper use of filters depends on the level of cleanliness required in individual facilities as

shown in Table 4.2.

Figure 4.2 Filtration

58


Table 4.2 Filters used in printing plant

Area Filter Type

Common Production Area 80 to 90% mass arrestance

Sheetfed Pressroom Final filter: 85% dust-spot efficiency

Film Processing (dust free requirement) Final filter: 90 to 95% dust-spot efficiency

Office 50 to 60% dust spot efficiency

Ref. ANSI/ASHRAE Standard 52.2 - 1999

4.3 Adsorption Air Cleaning

Adsorption is a surface phenomenon that gaseous contaminant molecules are diffused into the

macropores and micropores of adsorbent material. The net flow of the pollutant molecules is toward

the adsorbent surface when the concentration of the contaminant in the gas flow is greater than

that at the adsorbent surface. Activated carbon and molecular sieves are popular adsorbents.

4.4 Segregation

Effective segregation of workplaces helps prevent the spread of pollutants from the sources to

other clean areas of a plant. The general guidelines for segregation are:

1. Printing processes that emit considerable hazardous pollutants should be isolated in rooms

that are well-sealed except the door gaps. Such printing processes include film processing, plate

making and chemical storage. The air in isolated rooms is not allowed to freely mix with the air

in the remaining printing plant areas. Each isolated room should be served by a separate

mechanical ventilation system. Normally, the ventilation operates at 100% discharge to the

exhaust without recirculation of return air unless proper air treatment is available. Additional

local exhaust ventilation may be applied as appropriate.

2. On the contrary, offices, control rooms and canteen are relatively clean areas. They should be

separated from the majority production areas in order to prevent contamination. Separate

mechanical ventilation systems should be implemented. The use of recirculated air from the

production areas should not be allowed.

3. The loading area of a printing plant is usually polluted by combustion gases emitted from

delivery trucks during loading and unloading. The use of air curtain at the entrance is

recommended to minimize the transport of pollutants into the indoor environment. Moreover,

the indoor area adjacent to the loading area should be maintained at a positive pressure to

prevent infiltration. Ground-level local exhaust ventilation can remove vehicle exhaust from

the loading bay. Drivers are encouraged to turn off the engines while waiting.

59

OSH Research Report

Figure 4.3 Segregation of facilities in printing plant

4.5 Differential Pressure Control

In conjunction with segregation of workplaces, the differential pressure between two adjacent,

separated areas should be regulated to restrict the air leakage through the door undercut to a

single direction in compliance with the clean-to-less-clean principle. A negative pressure can be

obtained by providing an air flow rate of the supply lower than that of the exhaust, as illustrated

in Figure 4.3. Oppositely, a positive pressure can be obtained by providing an air flow rate of the

supply higher than that of the exhaust. A summary of differential pressure control in printing

plants is presented in Table 4.3.

Figure 4.4 Differential pressure control in pre-press room

60


Table 4.3 Differential pressure control in printing plant

Area Differential Pressure

Chemical Storage Negative

Plate Making Negative

Pressroom Equal

Binding Equal

Office Positive

Canteen Positive

4.6 Directional Airflow Control

The clean-to-less-clean airflow principle is also applicable to the ductwork design of an air-

conditioning system. The air movement should be from clean areas to areas of progressively higher

pollutant concentration. Figure 4.4 illustrates an example of a pressroom. Clean conditioned air

should be supplied to the zone occupied by workers while the exhaust should be placed near the

printing machine to remove the emissions. It is noted that the ceiling exhaust can encourage

stratification for effective removal of the hot, rising VOC emissions.

Figure 4.5 Directional airflow in pressroom

61

OSH Research Report

4.7 Local Exhaust Ventilation

Some sources may emit considerable pollutants that, practically, the abovementioned engineering

methods are not effective to control the indoor air quality. Examples in a printing plant include

sizable offset printing machines, photocopiers, film developers, plate makers etc. Under these

circumstances, local exhaust ventilation, as shown in Figure 4.6, may become the most cost-effective

method to capture the pollutants in the vicinity of the source immediately after emissions. The

polluted exhaust are then discharged to the outdoor environment, or treated before discharge.

The exhaust fan should be located at the discharge end of the duct system so that leakage into the

indoor environment is avoided.

Figure 4.6 Local exhaust ventilation

There are a number of conventional exhaust treatment options depending on the types of pollutants,

i.e. HEPA filtration for particulates, absorption and electric/gas-fired incineration for VOC. When

local exhaust ventilation is operating, the general supply air should be increased to provide make-

up air to replace the discharge air. Thus, the designed differential pressure can be maintained.

4.8 Source Control

As forklifts powered by gasoline, propane or LPG are commonly used in production areas and

warehouses, the combustion gas emissions may cause poor indoor air quality. Toxic carbon monoxide

due to incomplete combustion is of particular concern. Instead of increasing the outdoor air intake

for dilution, a better solution is to eliminate the source by replacement with electric forklifts.

62


5. Best Practices of Work

Besides the engineering control and mitigation measures, IAQ in printing plants can be effectively

improved by implementing proper practice of work in normal operation. The workers being aware

of IAQ should be capable of taking appropriate actions to lower the emissions of pollutants or

even remove the sources. The following useful practices are recommended:

i The use of automatic blanket wash systems should be considered wherever practicable (HSE

2004).

ii Only necessary amount of solvent or cleaning agent is used. Excessive use of chemicals causes

extra emissions of the vapours. Adopting cleaning rags would help reduce the consumption of

cleaning agent.

iii Containers of solvents, cleaning agents, fountain solutions, and inks should be tightly closed

after use to minimize the emissions.

iv Less harmful chemicals or processes available are preferred to substitute conventional ones. A

candidate substitute for existing chemical used may have the attributes that it can be function

effectively at lower concentration or it has lower vapour pressure. Moreover, it should not

cause any other hazards, such as flammability and corrosion. Probable substitutes available in

the industry are presented in Table 5.1.

Table 5.1 Less harmful chemical or process for substitution

Conventional Chemical/Process Substitute Use

Heat-set ink Ultraviolet (UV) ink Printing process

Photographic chemicals Diazo, vesicular, photopolymer,electrostatic films, and agentswithout hydroquinone

Presensitized plate Computer-to-plate Plate making

v In handling of chemicals, the use of automatic mechanical devices is recommended. For example,

pumps can be used to facilitate the filling of solvent containers. This can avoid unnecessary

spillage and direct contact of the chemical. More devices are presented in Table 5.2.

Table 5.2 Automatic mechanical devices for handling of chemicals

Device Function/Use

Automatic processor Direct pumping of replenishment solutions and drainage of spentsolvents to container

Automatic cleaner Cleaning of offset press

Pump Transferring fountain solution

Carousels mixing system Formulating ink

Film Development

63

OSH Research Report

vi During an operation in which the worker has to stay close to the source of contaminant, such as

cleaning of printing presses, the worker should stand in a position so that the air flows through

him before the contaminant source, as illustrated in Figure 5.1.

Figure 5.1 Proper position of worker with respect to contaminant source and airflow direction

vii Personal protection by respiratory protective equipment in general is not required in normal

operations of printing facilities. It may be needed for some emergency cleaning and maintenance

activities, e.g. dealing with spills. Routine maintenance of respirators is essential.

viii For dust-generating printing procedures, such as paper cutting (paper dust) and wed-fed printing

(starch powder), printing workers should wear filtering facepiece particulate respirators.

Particulate respirators meeting the NIOSH 42 CFR 84 N95 Standard should be used.

ix Waste ink, solvent and rags become unattended indoor VOC sources. Therefore, the waste

should be properly handled and removed from the indoor environment as soon as possible.

x Vacuum cleaning of dusty surfaces should be used instead of compressed air cleaning as the

latter will cause settled particulates to aerosolize again.

64


Good indoor air quality in a printing plant relies on the joint efforts of the employer, workers,

engineers and administrative staff. An IAQ management programme can best facilitate the

coordination of necessary activities to identify, correct and prevent IAQ problems. The

implementation of a management programme can also raise awareness in all staff for achieving

good IAQ. IAQMG (2003) has outlined the IAQ management strategies for offices and public places.

With appropriate modifications, the strategies can be applied to most printing plants.

Step 1: Allocation of responsibilities

• Appoint an IAQ manager responsible for the overall development and implementation of the

IAQ management programme. The ideal candidate will be someone in the senior management

level. The IAQ manager may directly report to the highest hierarchy of Safety and Health

Committee.

• Set up an IAQ management team comprising IAQ officers from different staff to assist the IAQ

manager. A desirable organisational structure for an IAQ management team is shown in Figure

6.1.

Figure 6.1 Organisational structure of IAQ management team

Step 2: Preparation performed by the IAQ manager

• Study the literature on IAQ in the printing industry to gain a basic understanding of the problems,

control strategies, mitigation measures and preventive actions.

• Be aware of new and existing legislative requirements, standards and guidelines; ensure that

these are fully understood by all staff members.

• Develop an IAQ Policy endorsed by the senior management; alternatively, the commitment to

good IAQ can be defined in either the Environmental Policy or the Safety and Health Policy.

• Organize IAQ Training Programme to help staff understand the sources and adverse health

effects of IAQ pollutants, and acquire knowledge and skill to control the pollutants below the

occupational exposure limits.

6. Management Programme

65

OSH Research Report

• Identify the potential IAQ problems that could be caused by the printing processes and chemicals

used.

• Identify poor engineering design and operation of the ventilation and filtration systems that

may cause IAQ problems.

Step 3: Review of staff activities

• Ensure that printing facilities and areas occupied by staff are properly placed so that air generally

flows though the workers before the printing machines (clean-to-less-clean principle).

• Assist IAQ assessment and investigation activities when required.

Step 4: Communication

• Document and communicate with all staff for issues relating to air pollutants in the printing

industry, i.e. chemical spillage and leakage incidents, reported SHS, reported outbreaks of

infection, IAQ assessment and investigation results, recommended guidelines etc.

• Provide a platform for receiving and responding to IAQ complaints.

Step 5: Investigation

• Use the questionnaire form (Appendix I) designed for IAQ in printing plants to conduct

questionnaire surveys to collect information from the staff.

• Analyse the data/information collected to identify potential IAQ problems.

• Conduct periodic walk-through inspections with the checklists provided in Appendix II.

• Conduct comprehensive IAQ assessments with detailed measurements. The data sheet provided

in Appendix III suggests the information needed to complete an assessment.

• Analyse the measurements, identify appropriate mitigation measures and implement them.

Step 6: Record keeping

• Keep records of IAQ-related complaints and follow-up actions.

• Keep records of IAQ questionnaire surveys to monitor progress, as indicators of IAQ performance.

• Keep records of walk-through inspections and comprehensive IAQ assessments conducted.

• Register all IAQ-related symptoms and illnesses reported by the occupants.

• Update Material Safety Data Sheet (MSDS) for the materials used and stored in the printing

plants.

66


Name (optional): Date:

Telephone (optional):

Part 1: IAQ-related information about your workplace1.1 Please rate the present condition of each of the following items (Circle one number between 1 and 7,

inclusive)

Item Very Poor Very Good

a Air quality 1 2 3 4 5 6 7

b Air freshness 1 2 3 4 5 6 7

c Air ventilation/circulation 1 2 3 4 5 6 7

d Air temperature 1 2 3 4 5 6 7

e Air humidity 1 2 3 4 5 6 7

1.2 During the past three months, have you experienced any of the following items? (Circle Y or N)

Item Yes No

a Unpleasant odours Y N

b Stuffy air Y N

c Too warm Y N

d Too cold Y N

e Too humid Y N

f Too dry Y N

1.3 During the past three months, have any of the following changes been made in your workplace?(Circle Y or N)

Change Yes No

a New carpeting Y N

b New flooring Y N

c New furnishing Y N

d New painted wall Y N

e New partition Y N

If you circle all N’s, please go to Q1.5.

Appendix I : Printing Plant Indoor Air Quality (IAQ) Questionnaire

67

OSH Research Report

1.4 Do any of the above changes cause the following pollutants? (Circle Y or N)

Pollutants Yes No

a Dust Y N

b Irritant fumes Y N

c Unpleasant odours Y N

1.5 Are there any air cleaning devices installed in your workplace? (Circle 1, 2 or 3)

1 Yes2 No → Go to Q 1.73 Do not know → Go to Q 1.7

1.6 Do the air cleaning devices significantly improve the indoor air quality? (Circle a number)

1 Yes2 No

1.7 For each of the following factors, do you believe that it has adversely affected the indoor air quality inyour workplace during the past three months? (Circle one number between 1 and 7, inclusive)

Factor Strongly StronglyAgree Disagree

a Chemical pollutants 1 2 3 4 5 6 7

b Microbiological pollutants 1 2 3 4 5 6 7

c Unpleasant odours 1 2 3 4 5 6 7

d Tobacco smoke 1 2 3 4 5 6 7

e Outdoor pollutants entering the building 1 2 3 4 5 6 7

f Poor air conditioning 1 2 3 4 5 6 7

g Insufficient ventilation 1 2 3 4 5 6 7

h Renovation works 1 2 3 4 5 6 7

i Overcrowding 1 2 3 4 5 6 7

j New furnishings/carpets 1 2 3 4 5 6 7

k Other factors (please specify) 1 2 3 4 5 6 7

1.8 Overall, how satisfied are you with the indoor air quality in your workplace? (Circle one number between1 and 7, inclusive)

Very Dissatisfied Very Satisfied

1 2 3 4 5 6 7

68


Part 2: IAQ-related information about your health2.1 During the past three months, have you had the following symptoms? (Circle one number between 1 and

7, inclusive)

Symptoms Always Never

a Dryness 1 2 3 4 5 6 7

Eye symptoms b Redness 1 2 3 4 5 6 7

c Watering 1 2 3 4 5 6 7

d Dry nose 1 2 3 4 5 6 7

Nasal symptomse Running nose 1 2 3 4 5 6 7

f Sneezing 1 2 3 4 5 6 7

g Stuffy nose or congestion 1 2 3 4 5 6 7

Throat symptomsh Dry cough 1 2 3 4 5 6 7

i Sore or dry throat 1 2 3 4 5 6 7

j Dryness 1 2 3 4 5 6 7

Skin problems k Itching skin 1 2 3 4 5 6 7

l Rash 1 2 3 4 5 6 7

m Difficulty in concentrating 1 2 3 4 5 6 7

n Dizziness 1 2 3 4 5 6 7

o Fever 1 2 3 4 5 6 7

Other symptoms p Headache 1 2 3 4 5 6 7

q Nausea 1 2 3 4 5 6 7

r Shortness of breath 1 2 3 4 5 6 7

s Unusual fatigue 1 2 3 4 5 6 7

Others (please specify): 1 2 3 4 5 6 7

If you never have any of the above symptoms (i.e. circle all 7’s), please go to Part 3.

2.2 Do the symptoms usually improve when you temporarily leave your workplace? (Circle a number)

1 Yes, become less severe2 No. stay the same3 No, become worse

2.3 Do the symptoms lower your working performance/productivity? (Circle a number)

1 Yes2 No

69

OSH Research Report

2.4 Did the symptoms cause you to take sick leave during the past three months? (Circle a number)

1 Yes2 No → Go to Q 2.6

2.5 How long (in total) was the sick leave? (Circle a number)

1 Less than 1/2 day2 1/2 to 1 day3 2 to 4 days4 5 to 7 days5 More than 7 days

2.6 Select atmost three serious symptoms that frequently cause you to take sick leave? (Circle at most threealphabets from a - l)

Symptoms

a Eye symptoms

b Nasal symptoms

c Throat symptoms

d Skin problems

e Difficulty in concentrating

f Dizziness

g Fever

h Headache

i Nausea

j Shortness of breath

k Unusual fatigue

l Others (please specify):

2.7 Have you sought medical treatment for your symptoms? (Circle a number)

1 Yes2 No

2.8 Does anyone around you suffer from the same symptoms as you? (Circle a number)

1 Yes2 No

70


2.9 For each of the following factors, do you believe that it has been a major factor causing the symptoms asmentioned in Q 2.1 during the past three months? (Circle one number between 1 and 7, inclusive)

Factor Strongly StronglyAgree Disagree

a Chemical pollutants 1 2 3 4 5 6 7

b Microbiological pollutants 1 2 3 4 5 6 7

c Unpleasant odours 1 2 3 4 5 6 7

d Tobacco smoke 1 2 3 4 5 6 7

e Outdoor pollutants entering the building 1 2 3 4 5 6 7

f Poor air conditioning 1 2 3 4 5 6 7

g Insufficient ventilation 1 2 3 4 5 6 7

h Renovation works 1 2 3 4 5 6 7

i Overcrowding 1 2 3 4 5 6 7

j New furnishings/carpets 1 2 3 4 5 6 7

k Other factors (please specify): 1 2 3 4 5 6 7

Part 3: IAQ-related information about you and your specific job

3.1 Your gender?

1 Female2 Male

3.2 Your age?

1 Under 252 25 to 343 35 to 444 45 to 545 55 or above

3.3 What is your occupation? (Circle the most appropriate number)

1 Managerial/Executive2 Professional3 Technician4 Clerical/Secretarial5 Manual worker/Blue collar6 Others (please specify):

71

OSH Research Report

3.4 How long have you been working in the printing industry?

1 Less than 1 year2 1 to 5 years3 6 to 10 years4 11 to 20 years5 More than 20 years

3.5 How long have you been working in this printing company?

1 Less than 1 year2 1 to 5 years3 6 to 10 years4 11 to 20 years5 More than 20 years

3.6 How many hours per day do you spend in your workplace?

1 Fewer than 4 hours2 4 to 6 hours3 7 to 9 hours4 10 to 12 hours5 More than 12 hours

Thank you very much for completing this questionnaire.

72


Appendix II : IAQ Checklist

Conducted by: Date:

Building: Floor/Room:

Part 1: Printing Plant

Yes No Remark

1 Is indoor environment too hot or too cold?

2 Is indoor environment too humid or too dry?

3 Any unpleasant odours?

4 Any odours of ammonia?

5 Is supply air weak?

6 Is supply or return airflow obstructed?

7 Are any windows open in mechanically

ventilated area?

8 Any chemical waste/storage room doors

opened?

9 Any signs of poor or reverse differential

pressure in chemical waste/storage rooms?

10 Are ceiling tiles near supply air diffusers

stained?

11 Any unsealed chemicals, such as ink, solvent,

and cleaning agent, containers?

12 Any spills of chemical agents?

13 Any baths of ink, solvent, and cleaning agent

left exposed to indoor air without a local

exhaust system?

14 Any mould or mildew growth on shower

heads/taps?

15 Any other signs of mould or mildew growth?

16 Any visible surfaces dusty?

17 Any special sources of pollutants other than

printing machines? (e.g. forklift, cigarette

smoking etc.)

� �

� �

� �

� �

� �

� �

� �

� �

� �

� �

� �

� �

� �

� �

� �

� �

� �

73

OSH Research Report

Part 2: Engineering Facilities

AHU Room Yes No Remark

1 Any sign of water damage or standing water

in AHU?

2 Any mould or mildew growth inside at AHU?

3 Any mould or mildew growth on cooling coil?

4 Any sources of pollutants in AHU room? (e.g.

paint and lubricant etc.)

5 Are air filters overloaded?

Outdoor Air Intake Yes No Remark

6 Is outdoor air intake close to any building

exhausts, including those of chemical fume

hoods?

7 Is outdoor air intake close to cooling tower?

8 Is outdoor air intake close to other source of

pollutants, i.e. vehicle exhaust and nearby

construction work etc.?

9 Is outdoor air intake contaminated by standing

water and bird droppings etc.?

10 Is outdoor air intake obstructed by leaves and

debris etc.?

Cooling Tower Yes No Remark

11 Any serious growth of slime or algae on

surfaces of cooling tower?

12 Is emission of water mist high?

13 Is cooling tower located near the outdoor air

intake?

� �

� �

� �

� �

� �

� �

� �

� �

� �

� �

� �

� �

� �

74


Construction/Renovation Areas Yes No Remark

14 Any air leakage through construction barrier

used to isolate the indoor construction/

renovation area?

15 Any air leakage from sealing of ventilation

system in construction/renovation area?

16 Is outlet of temporary local exhaust located

near outdoor air intake or windows?

17 Are any containers of paint, solvent, adhesive

or cleaning agent left unsealed while not in use?

18 Is outdoor air intake contaminated by emission

from nearby construction works?

� �

� �

� �

� �

� �

75

OSH Research Report

Appendix III : Data Sheet for Short-Term IAQ Sampling

AH

U N

o.

Co

nd

uct

ed b

y:

Dat

e:

Bu

ildin

g:

Flo

or/

Ro

om

:

Typ

e o

f fa

cilit

y:

Air

-co

nd

itio

ned

are

a (m

2):

Nu

mb

er o

f o

ccu

pan

ts:

Cei

ling

hei

gh

t (m

):

Star

t ti

me:

Fi

nis

hed

tim

e:

IAQ

par

amet

ers

Sam

plin

g P

oin

tC

O2

CO

NO

2O

3TV

OC

Form

ald

ehyd

eR

SPB

acte

ria

Rad

on

Tem

per

atu

reR

H(p

pm

)(p

pm

)(p

pm

)(p

pm

)(m

g/m

3 )(p

pm

)(m

g/m

3 )(c

fu/m

3 )(p

Ci/L

)(o

C)

(%)

AH

U o

per

atio

ns

Sup

ply

Air

Ret

urn

Air

Ou

tdo

or

Air

Air

Sp

eed

Du

ct S

ize

Tem

per

atu

reA

ir S

pee

dD

uct

Siz

eTe

mp

erat

ure

Air

Sp

eed

Du

ct S

ize

Tem

per

atu

re(m

/s)

L (m

) x

W (

m)

(oC

)(m

/s)

L (m

) x

W (

m)

(oC

)(m

/s)

L (m

) x

W (

m)

(oC

)

An

y O

bse

rvat

ion

/su

gg

esti

on

s:

76


1. ASHRAE (American Society of Heating, Refrigerating and Air-Conditioning Engineers, Inc.) 1999. Chapter 3

- Commercial and Public Buildings, ASHRAE Handbooks: Applications, SI Edition, ASHRAE, Atlanta, Georgia.

2. ASHRAE (American Society of Heating, Refrigerating and Air-Conditioning Engineers, Inc.) 2003. Chapter

18 - Printing Plants, ASHRAE Handbooks: Applications, SI Edition, ASHRAE, Atlanta, Georgia.

3. ASHRAE (American Society of Heating, Refrigerating and Air-Conditioning Engineers, Inc.) 1999. ANSI/

ASHRAE Standard 52.2-1999, Method of Testing General Ventilation Air-Cleaning Devices for Removal

Efficiency by Particle Size, ASHRAE, Atlanta, Georgia.

4. ASHRAE Standard 62-2001 .........

5. ASHRAE (American Society of Heating, Refrigerating and Air-Conditioning Engineers, Inc.) 2001b. Chapter

9 - Indoor Environment Health, ASHRAE Handbooks: Fundamentals, SI Edition, ASHRAE, Atlanta, Georgia.

6. EHS 1997. Consultancy study on indoor air pollution in offices and public places in Hong Kong, EHS

Consultants Limited.

7. IAQMG (Indoor Air Quality Management Group) 2003. Guidance Notes for the Management of Indoor Air

Quality in Offices and Public Places, The Government of the Hong Kong Special Administrative Region.

8. Health & Safety Executive 2004. Printing - Control guidance sheets, http://www.hse.gov.uk/printing/

coshhessentials.htm#guidance.

9. Leung, M. and Chan, A. Better Hospital Indoor Air Quality, Proceedings of the Symposium on Legionnaires’

Disease and other Respiratory Infections and their Prevention, Hong Kong, 12 December 2003, pp. 41-49.

10. NIOSH 1994. NIOSH Manual of Analytical Methods, National Institute for Occupational Safety and Health

Publication 94-113. 4th edition.

11. NIOSH 2000. NIOSH Hazard Review, Carbonless Copy Paper, U.S. Department of Health and Human Services,

Public Health Service, Centers for Disease Control and Prevention, National Institute for Occupational Safety

and Health. DHHS (NIOSH) Publication No. 2001-107.

12. NIOSH 2003. NIOSH Pocket Guide to Chemical Hazards (NPG), NIOSH Publication No. 97-140, 3rd Printing.

13. Occupational Safety and Health Branch, HKSAR Labour Department 2000. The Protection of Workers’ Health

Series - Solvent.

14. Occupational Safety and Health Branch, HKSAR Labour Department 2002. Code of Practice on Control of

Air Impurities (Chemical Substances) in the Workplace, 1st edition.

15. OSHA 1991. Chemical Information Manual, OSHA Instruction CPL 2-2.43A.

16. OSHA 2001. Sampling and Analytical Methods. (http://www.osha-slc.gov/dts/sltc/methods/index.html).

17. WHO (World Health Organization) 2000. Guidelines for Air Quality, WHO, Geneva.

References

indoor air quality (eng) - oshc · 40 indoor air quality for printing plants tables table 3.1 :...

Documents