Indoor Air Quality in

Commercial and

Institutional Buildings

OSHA 3430-04 2011
Occupational Safety and Health Act of 1970

“To assure safe and healthful working conditions

for working men and women; by authorizing

enforcement of the standards developed under

the Act; by assisting and encouraging the States in

their efforts to assure safe and healthful working

conditions; by providing for research, information,

education, and training in the field of occupational

safety and health.”

This publication provides a general overview of a

particular standards-related topic. This publication

does not alter or determine compliance responsibilities

which are set forth in OSHA standards, and the

Occupational Safety and Health Act of 1970. Moreover, because interpretations and enforcement policy

may change over time, for additional guidance on

OSHA compliance requirements, the reader should

consult current administrative interpretations and

decisions by the Occupational Safety and Health

Review Commission and the courts.

Material contained in this publication is in the public

domain and may be reproduced, fully or partially,

without permission. Source credit is requested

but not required.

This information will be made available to sensoryimpaired individuals upon request. Voice phone:

(202) 693-1999; teletypewriter (TTY) number: 1-877-

889-5627.
Indoor Air Quality in

Commercial and Institutional

Buildings

Occupational Safety and Health Administration

U.S. Department of Labor

OSHA 3430-04

2011

The guidance is advisory in nature and informational in

content. It is not a standard or regulation, and it neither

creates new legal obligations nor alters existing obligations

created by OSHA standards or the Occupational Safety and

Health Act. Pursuant to the OSH Act, employers must

comply with safety and health standards and regulations

issued and enforced by either OSHA or by an OSHAapproved State Plan. In addition, the Act’s General Duty

Clause, Section 5(a)(1), requires employers to provide their

workers with a workplace free from recognized hazards

likely to cause death or serious physical harm.
Contents

Introduction 3

Background 3

Benefits of Mitigation of IAQ Problems 4

Health Effects 4

Sources of Indoor Air Pollutants 5

Common Pollutant Categories 6

Prevention or Control IAQ Problems 6

IAQ Management Approach 6

Identification and Assessment 7

Control Methods 7

Seeking Professional Assistance 8

Applicable Standards and

Regulations 9

OSHA Standards 9

Standard Interpretations 9

State Programs 10

National Consensus Standards 10

OSHA Assistance 11

Appendix A: Common Indoor Air

Contaminants 14

Appendix B: Steps to Improve

Indoor Air Quality 17

Appendix C: HVAC System

Maintenance Checklist 18

Appendix D: Investigating IAQ

Problems and Complaints 19

Appendix E: Selected Resources 20

Hazard Recognition 20

Evaluation and Control 21

Appendix F: OSHA-Sponsored

EnvironmentalTobacco Smoke

Workshops 23

Workshops I - III 23

References 24

2

Occupational Safety and

Health Administration
Introduction

Indoor air quality (IAQ) is a major concern to

businesses, schools, building managers, tenants,

and workers because it can impact the health,

comfort, well-being, and productivity of the building

occupants. OSHA recognizes that poor IAQ can be

hazardous to workers’ health and that it is in the

best interest of everyone that building owners,

managers, and employers take a proactive approach

to address IAQ concerns.

This OSHA guidance document on IAQ provides

practical recommendations that will help prevent

or minimize IAQ problems in commercial and

institutional buildings, and help resolve such

problems quickly if they do arise. It provides flexible

guidance to employers to help them keep their

buildings free of pollutants or conditions that lead

to poor IAQ. It also provides information on good

IAQ management, including control of airborne

pollutants, introduction and distribution of adequate

make-up air, and maintenance of an acceptable

temperature and relative humidity. Temperature and

humidity are important because thermal comfort

underlies many complaints about “poor air quality.”

Some of the information presented here has been

derived from the Environmental Protection Agency’s

(EPA) report, “An Office Building Occupant’s Guide

to IAQ” (1)1 and other documents listed in Appendix

E, Selected Resources. The issue of environmental

tobacco smoke will only be addressed in Appendix

F, or indirectly in discussions of air quality relative to

some possible components of tobacco smoke, e.g.,

carbon monoxide, carbon dioxide, particulates, etc.

In 1998, OSHA conducted a series of three workshops

on this issue and the proceedings of these workshops

were published in 1999. See Appendix F for more

information.

This document is directed primarily at employers,

building owners and managers, and others

responsible for building maintenance, but may also

be used as a basic reference for all those involved

in IAQ issues. Furthermore, information presented

here can help with the decision of whether or not

the services of an outside professional may be

needed. The advice of a medical professional should

always be sought if there are any immediate health

issues. Contractors and other professionals (e.g.,

industrial hygienists or other environmental health

and safety professionals) who respond to IAQ

concerns, as well as members of the general public,

may also find this information helpful.

Background

IAQ has been identified by the EPA as one of the

top five most urgent environmental risks to public

health (2). The Centers for Disease Control and

Prevention (CDC) estimates that the majority of

Americans spend approximately 90 percent of their

time indoors (3). On average, office workers spend

approximately 40 hours a week in office buildings.

These workers also study, eat, drink, and, in certain

work settings, sleep in enclosed environments

where make-up air (i.e., fresh air added to recirculated air) may be compromised. For this

reason, some experts believe that more people may

suffer from the effects of indoor air pollution than

from outdoor air pollution.

Each building has its own set of circumstances.

Air quality may be determined by the site of the

building, its original design, renovations, whether

air handling systems have been maintained,

occupant densities, activities conducted within the

building, and the occupants’ satisfaction with their

environment. IAQ problems can arise from a single

source or any combination of factors. Inadequate

IAQ may begin with poor building design or failure

of the building enclosure or envelope (roof, facade,

foundation, etc.). Other issues may be associated

with the location of the building and mixed uses of

the building. Many common IAQ problems are

associated with improperly operated and maintained

heating, ventilating and air-conditioning (HVAC)

systems, overcrowding, radon, moisture incursion

and dampness, presence of outside air pollutants,

and the presence of internally generated contaminants such as use of cleaning and disinfecting

supplies and aerosol products, off-gassing from

materials in the building, and use of mechanical

equipment. Improper temperature and relative

humidity conditions can also present problems,

especially concerning comfort.

Many IAQ complaints are associated with flaws

in building design and by inadequate routine

preventive maintenance of building enclosures

(envelopes), plumbing, and HVAC systems (2, 4, 5).

To resolve many IAQ problems, a preventive maintenance program should be established based on

the system’s recommended maintenance schedule

outlined by the architect or engineer, the manufacturer, or an HVAC professional. Regular preventive

maintenance not only ensures that systems are

operating properly, but also can result in cost

savings, improved operating efficiency, and

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1The numbers in parentheses refer to specific entries in the last

section of this document titled “References.”
Research has linked building dampness with

significant health effects. Numerous species of

bacteria and fungi, in particular filamentous fungi

(mold), can contribute significantly to indoor air

pollution (4, 15-20). Whenever sufficient moisture is

present within workplaces, these microbes can grow

and affect the health of workers in several ways.

Workers may develop respiratory symptoms,

allergies, or asthma (8). Asthma, cough, wheezing,

shortness of breath, sinus congestion, sneezing,

nasal congestion, and sinusitis have all been

associated with indoor dampness in numerous

studies (21-23). Asthma is both caused by and

worsened by dampness in buildings. The most

effective means to prevent or minimize adverse

health effects is to determine the sources of

persistent dampness in the workplace and eliminate

them. More details on preventing mold-related

problems can be found in the OSHA publication

titled: “Preventing Mold-Related Problems in the

Indoor Workplace” (17). Other environmental factors

such as poor lighting, stress, noise, and thermal

discomfort may cause or contribute to these health

effects (8).

increased worker productivity (6). The U.S. Green

Building Council (USGBC), among others, has

demonstrated that IAQ issues can be readily and

practically addressed when building systems are

retrofitted for energy efficiency.

(http://www.usgbc.org/DisplayPage.aspx?CMSPageID=221#v2008)

Benefits of Mitigation of IAQ Problems

Good IAQ in buildings is an important component

of a healthy indoor environment. It contributes to a

favorable and productive environment for building

occupants, giving them a sense of comfort, health,

and well-being. Significant increases in worker

productivity have also been demonstrated when the

air quality was adequate (6). Research has also

shown that workers in buildings with adequate air

quality have reduced rates of symptoms related to

poor air quality (7).

Health Effects

Symptoms related to poor IAQ are varied depending

on the type of contaminant. They can easily be

mistaken for symptoms of other illnesses such as

allergies, stress, colds, and influenza. The usual clue

is that people feel ill while inside the building, and

the symptoms go away shortly after leaving the

building, or when away from the building for a

period of time (such as on weekends or a vacation).

Health or symptom surveys, such as the one

included in Appendix D, have been used to help

ascertain the existence of IAQ problems.

Failure of building owners and operators to respond

quickly and effectively to IAQ problems can lead to

numerous adverse health consequences. Health

effects from indoor air pollutants may be experienced soon after exposure or, possibly, years later

(8, 9, 10). Symptoms may include irritation of

the eyes, nose, and throat; headaches; dizziness;

rashes; and muscle pain and fatigue (11, 12, 13, 14).

Diseases linked to poor IAQ include asthma and

hypersensitivity pneumonitis (11, 13). The specific

pollutant, the concentration of exposure, and the

frequency and duration of exposure are all

important factors in the type and severity of health

effects resulting from poor IAQ. Age and preexisting

medical conditions such as asthma and allergies

may also influence the severity of the effects. Longterm effects due to indoor air pollutants may include

respiratory diseases, heart disease, and cancer, all of

which can be severely debilitating or fatal (8, 11, 13).

4

Occupational Safety and

Health Administration
Renovation Activities: When painting and other

renovations are being conducted, dust or other

by-products of the construction materials are

sources of pollutants that may circulate through a

building. Isolation by barriers and increased

ventilation to dilute and remove the contaminants

are recommended.

Local ExhaustVentilation: Kitchens, laboratories,

maintenance shops, parking garages, beauty and

nail salons, toilet rooms, trash rooms, soiled laundry

rooms, locker rooms, copy rooms and other

specialized areas may be a source of pollutants

when they lack adequate local exhaust ventilation.

Building Materials: Disturbing thermal insulation or

sprayed-on acoustical material, or the presence of

wet or damp structural surfaces (e.g., walls, ceilings)

or non-structural surfaces (e.g., carpets, shades),

may contribute to indoor air pollution.

Building Furnishings: Cabinetry or furniture made

of certain pressed-wood products may release

pollutants into the indoor air.

Building Maintenance: Workers in areas in which

pesticides, cleaning products, or personal-care

products are being applied may be exposed to

pollutants. Allowing cleaned carpets to dry without

active ventilation may promote microbial growth.

Occupant Activities: Building occupants may be

the source of indoor air pollutants; such pollutants

include perfumes or colognes.

Sources of Indoor

Air Pollutants

The relative importance of any single source

depends on how much of a given pollutant it emits,

how hazardous those emissions are, occupant

proximity to the emission source, and the ability

of the ventilation system (i.e., general or local) to

remove the contaminant. In some cases, factors

such as the age and maintenance history of the

source are significant.

Sources of indoor air pollution may include:

Building Site or Location: The location of a building

can have implications for indoor pollutants.

Highways or busy thoroughfares may be sources

of particulates and other pollutants in nearby

buildings. Buildings sited on land where there was

prior industrial use or where there is a high water

table may result in leaching of water or chemical

pollutants into the building.

Building Design: Design and construction flaws

may contribute to indoor air pollution. Poor

foundations, roofs, facades, and window and door

openings may allow pollutant or water intrusion.

Outside air intakes placed near sources where

pollutants are drawn back into the building (e.g.,

idling vehicles, products of combustion, waste containers, etc.) or where building exhaust reenters into

the building can be a constant source of pollutants.

Buildings with multiple tenants may need an

evaluation to ensure emissions from one tenant do

not adversely affect another tenant.

Building Systems Design and Maintenance: When

the HVAC system is not functioning properly for any

reason, the building is often placed under negative

pressure. In such cases, there may be infiltration

of outdoor pollutants such as particulates, vehicle

exhaust, humid air, parking garage contaminants, etc.

Also, when spaces are redesigned or renovated, the

HVAC system may not be updated to accommodate

the changes. For example, one floor of a building

that housed computer services may be renovated

for offices. The HVAC system would need to be

modified for office employee occupancy (i.e., modifying temperature, relative humidity, and air flow).

I N D O O R A I R Q U A L I T Y I N C O M M E R C I A L A N D I N S T I T U T I O N A L B U I L D I N G S 5
Prevention and Control of

IAQ Problems

IAQ Management Approach

Ideally, an employer should use a systematic

approach when addressing air quality in the workplace. The components of a systematic approach for

addressing IAQ are the same as those for an overall

safety and health program approach, and include

management commitment, training, employee involvement, hazard identification and control, and

program audit. Management needs to be receptive

to potential concerns and complaints, and to train

workers on how to identify and report air quality

concerns. If employees express concerns, prompt

and effective assessment and corrective action is the

responsibility of management.

It is recommended that building owners/managers

develop and implement an IAQ management plan to

address, prevent, and resolve IAQ problems in their

specific buildings. The EPA’s report, IAQ Tools for

Office Buildings, provides a set of flexible and

specific activities that can be useful to building

owners/managers for developing such a plan. A key

feature of the plan is the selection of an IAQ Coordinator. The role and functions of an IAQ Coordinator

are described in Section 3 of the EPA’s report, IAQ

Tools for Schools Action Kit (24). Other critical

features of the plan include establishing necessary

IAQ policies, assessing the current status of IAQ in

buildings through periodic inspections, maintaining

appropriate logs and checklists, performing

necessary repairs and upgrades, and implementing

follow-up assessments or other needed actions.

Employers who lease space should be familiar with

the building management’s program and methods

for mitigating or resolving indoor air quality problems. It is especially important for employers to

know who to contact in buildings where there is

mixed use and pollutants are emanating from other

sources in the building. Employers should negotiate

leases that specify IAQ performance criteria. For

example, a lease should specify that the space be

ventilated with outdoor air while occupied and at a

rate described in ASHRAE 62.1 Ventilation for

Acceptable Indoor Air Quality.

An important management strategy is to foster a

team approach for problem solving and consensus

building. The IAQ Team should include, but not

necessarily be limited to, building occupants,

administrative staff, facility operators, custodians,

building healthcare staff, contract service providers,

and other interested parties.

Common Pollutant

Categories

Although there are numerous indoor air pollutants

that can be spread through a building, they typically

fall into three basic categories: biological, chemical,

and particle (1).

Biological

Excessive concentrations of bacteria, viruses, fungi,

dust mites, animal dander, and pollen may result

from inadequate maintenance and housekeeping,

water spills, inadequate humidity control,

condensation, or water intrusion through leaks in

the building envelope or flooding.

Chemical

Sources of chemical pollutants (gases and vapors)

include emissions from products used in the

building (e.g., office equipment; furniture, wall

and floor coverings; pesticides; and cleaning and

consumer products), accidental spills of chemicals,

products used during construction activities such as

adhesives and paints, and gases such as carbon

monoxide, formaldehyde, and nitrogen dioxide,

which are products of combustion.

Particle (Non-biological)

Particles are solid or liquid, non-biological, substances that are light enough to be suspended in the

air. Dust, dirt, or other substances may be drawn

into the building from outside. Particles can also be

produced by activities that occur in buildings such

as construction, sanding wood or drywall, printing,

copying, and operating equipment.

Some of the most common indoor air pollutants,

and the means to control or prevent them, are

discussed in Appendix A.

6

Occupational Safety and

Health Administration
the effectiveness of ventilation (5, 26), and excessive population density (e.g., overcrowding).

• Ensure that good housekeeping practices are

being applied.

• Ensure that routine preventive maintenance and

upkeep of buildings is being performed. A

preventive maintenance program provides the

care to all building systems and components that

keeps them operating at peak performance

according to manufacturer’s specifications, and

also allows for early detection of problems

(1, 18).

• Ensure that scheduled renovations are isolated

from the building’s general dilution ventilation

system when occupants are in the building.

Control Methods

There are three basic control methods for lowering

concentrations of indoor air pollutants:

1. Source management

Source management includes removal, substitution,

and enclosure of sources. It is the most effective

control method when it can be applied practically.

For example, the U.S. Consumer Product Safety

Commission recommends installing carpets that are

low-volatile organic compound (VOC) emitters, and

encourages consumers to ask retailers or installers

about the carpet industry’s voluntary “green label”

program for new carpets (27). According to the

carpet industry, the green and white logo displayed

on carpet samples informs the consumer that the

specific manufacturer’s product has been tested by

an independent laboratory and has met the criteria

for very low emissions (28). The label, however,

is not a guarantee that the carpet will not cause

health problems (27). Another example is that the

employer can set up temporary barriers or place the

space under negative pressure relative to adjoining

areas to contain the pollutants during construction

activities.

2. Engineering controls

a. Local exhaust

Local exhaust, such as a canopy hood, is very

effective in removing point sources of pollutants

before they can be dispersed into the building’s

indoor air.

b. General dilution ventilation

General dilution ventilation systems, when properly designed, operated, and maintained, will

control normal amounts of air pollutants. A welldesigned and functioning HVAC system controls

temperature and relative humidity levels to

Lastly, following up with affected personnel will

serve to validate the effectiveness of the mitigation

activities. For more information about the IAQ

management approach, refer to OSHA’s Safety and

Health Topics Page on Injury and Illness Prevention

Programs.

(http://www.osha.gov/dsg/topics/safetyhealth/index.html).

Identification and Assessment

Methods used in an IAQ investigation may include

identifying pollutant sources, evaluating the HVAC

system performance, observing production

processes and work practices, measuring

contamination levels and employee exposures,

providing medical testing or physical examinations,

conducting employee interviews, and reviewing

records of medical tests, job histories, and injuries

and illnesses. The Appendices provide resources

and checklists that building owners, managers, and

occupants can use to investigate IAQ complaints,

document walkthrough inspections, and correct

IAQ problems.

To prevent IAQ problems effectively and efficiently,

building managers should know and understand

the history of the building (construction, uses,

maintenance, etc.). If possible, owners and managers should maintain blueprints and construction

documents, including information about any

renovations of the building.

Some important practices include:

• Inspect and assess the building envelope, including the roof, walls, and foundation, and promptly

respond to identified problems. Routinely check

the building for water leaks, seals around doors

and windows, and any visible damp or moist

parts of the building. Clean and dry any damp or

wet building materials and furnishings within 24

to 48 hours after detection to prevent the growth

of mold.

• Ensure and validate that the building is

maintained under a slight positive pressure (i.e.,

air comes out of the building when exterior

doors are opened).

• Check whether the temperature and humidity are

maintained in a recommended comfort range

(temperature: 68 to 78 degrees and relative

humidity: 30% to 60%) (25).

• Ensure that routine maintenance of the HVAC

system is being performed, including the

performance of the system bringing outdoor air

into the building. (1).

• Monitor carbon dioxide (CO2) levels. The carbon

dioxide levels can be used as a rough indicator of

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storing food properly, and choosing cleaning

products and methods that minimize the

introduction of pollutants into the building (18).

These steps are outlined in Appendix B.

Seeking Professional Assistance

Some indoor air problems can be resolved when

good practices are put in place to control

contaminants and building personnel follow good

housekeeping approaches. Other problems may be

difficult to resolve, however, and may require

outside assistance. A building owner or manager

may first want to consult local, state, or federal

government agencies (e.g., education, health,

environmental protection, or agriculture agencies)

for assistance or direction in solving IAQ problems.

These governmental agencies may be able to help

an employer identify the types of experts who could

best assist them.

Examples of experts include:

• Structural engineers - address issues with

structural elements such as corrosion problems

in a building’s foundation;

• Architects - responsible for designing the

building envelope and can mitigate water

intrusion problems by designing vapor barriers;

• Mechanical engineers - test and balance HVAC

systems and may be able to assess and recommend repairs/replacement of HVAC systems and

local exhaust ventilation systems; and

• Industrial hygienists - assess general IAQ

parameters such as air changes in a building,

carbon dioxide levels, carbon monoxide levels,

and other indoor pollutants, and also evaluate

contaminant levels.

There may be private firms or consultants in your

area with experience in IAQ work. Such firms may

be found in general resources such as a telephone

directory (e.g., under “Engineers,” “Environmental

and Ecological Services,” “Laboratories-Testing,” or

“Industrial Hygiene Consultants”), on the Internet,

or by asking building owners/managers for referrals.

Some professionals who work with IAQ issues must

meet licensing and certification requirements to

practice in their disciplines. A consultant should

base any testing recommendations or protocol on

a thorough visual inspection, walkaround, and

interviews with building occupants.

provide thermal comfort, distributes adequate

amounts of outdoor air to meet the ventilation

needs of building occupants, and also dilutes and

removes odors and other contaminants. Testing

and rebalancing of HVAC systems are essential

when partitions are moved in buildings. Appendix C contains an HVAC System Maintenance

Checklist that can be used to assist in routine

maintenance of the HVAC system. For certain

situations, such as painting and carpet cleaning,

temporarily increasing ventilation can help dilute

the concentration of vapors in the air.

c. Air cleaning

Air cleaning primarily involves the removal of

particles from the air as the air passes through

the HVAC equipment. Most HVAC system

filtration is provided to keep dirt off of coil

surfaces to promote heat transfer efficiency.

Most smudging observed around air supply

diffusers in a ceiling result from entrainment

(trapping) of dirt particles in the space that

accumulate there because of poor housekeeping.

3. Administrative controls

a. Work Schedule

Through scheduling, managers can significantly

reduce the amount of pollutant exposure in their

buildings. For instance:

1. Eliminate or reduce the amount of time a

worker is exposed to a pollutant (i.e., scheduling maintenance or cleaning work to be

accomplished when other building occupants

are not present).

2. Reduce the amount of chemicals being used

by or near workers (i.e., limit the amount of

chemicals being used by the worker during

maintenance or cleaning activities).

3. Control the location of chemical use (i.e.,

perform maintenance work on moveable

equipment in a maintenance shop as opposed

to the general area, or locate the equipment

(e.g., printers, copiers) in a separate room).

b. Education

Education of building occupants regarding IAQ

is important (29). If occupants are provided with

information about the sources and effects of

pollutants under their control, and about the

proper operation of the ventilation system, they

can alert their employer and/or take action to

reduce their personal exposure.

c. Housekeeping

Housekeeping practices should include preventing dirt from entering the environment (using, for

example, walk-off mat systems), removing dirt

once it is in the building, disposing of garbage,

8

Occupational Safety and

Health Administration
Applicable Standards and Regulations

OSHA does not have a general IAQ standard, but does provide guidelines addressing the most common

workplace complaints about IAQ, which are typically related to temperature, humidity, lack of outside air

ventilation, or smoking. OSHA standards address potential hazardous conditions leading to serious physical

harm or death. Such standards may include those for specific air contaminants, ventilation systems, or the

General Duty Clause of the Occupational Safety and Health Act of 1970 (OSH Act). This section highlights

OSHA standards, standards interpretations (official OSHA letters of interpretation of its standards), and

national consensus standards related to IAQ.

OSHA Standards

All OSHA regulations, interpretations, and the OSH Act can be found on www.osha.gov. Important OSHA

statues and standards include:

• Occupational Safety and Health Act of 1970

Section 5(a)(1), often referred to as the General Duty Clause, requires employers to “furnish to each

of his employees employment and a place of employment which are free from recognized hazards

that are causing or are likely to cause death or serious physical harm to his employees.”

Section 5(a)(2) requires employers to “comply with occupational safety and health standards

promulgated under this Act.”

Some of the applicable OSHA Standards are:

• 29 CFR 1904, Recording and Reporting Occupational Injuries and Illnesses.

• 29 CFR 1910.94, Ventilation.

• 29 CFR 1910.1000, Air Contaminants.

• 29 CFR 1910.1048, Formaldehyde.

• 29 CFR 1910.1450, Occupational exposure to hazardous chemicals in laboratories.

Standard Interpretations

• Enforcement policy for respiratory hazards not covered by OSHA Permissible Exposure Limits.

(January 24, 2003.)

https://www.osha.gov/pls/oshaweb/owadisp.show_document?p_table=INTERPRETATIONS&p_id=24749.

• Air monitoring results, citations, and employee exposure records. (March 27, 2002.)

https://www.osha.gov/pls/oshaweb/owadisp.show_document?p_table=INTERPRETATIONS&p_id=24261.

• The use of ozone gas from ozone generators in a large room. (April 3, 1995.)

https://www.osha.gov/pls/oshaweb/owadisp.show_document?p_table=INTERPRETATIONS&p_id=21753.

• Request for a list of all OSHA-regulated air contaminants. (March 22, 1995.)

https://www.osha.gov/pls/oshaweb/owadisp.show_document?p_table=INTERPRETATIONS&p_id=21731.

• Record retention requirements for indoor air quality documents and reports. (August 1, 2002.)

http://www.osha.gov/pls/oshaweb/owadisp.show_document?p_table=INTERPRETATIONS&p_id=24255.

• Reiteration of existing OSHA policy on indoor air quality: office temperature and environmental tobacco

smoke. (February 23, 2003.)

http://www.osha.gov/pls/oshaweb/owadisp.show_document?p_table=INTERPRETATIONS&p_id=24602.

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State Programs

The Occupational Safety and Health Act of 1970 (OSH Act) encourages states to develop and operate their

own job safety and health plans. States with plans approved and monitored by OSHA under section 18(b)

of the OSH Act must adopt standards and enforce requirements that are at least as effective as federal

requirements. There are currently 27 State Plan states and territories: Twenty-two of these states and

territories administer plans covering both private and public (state/territory and local government) workers;

the other plans, Connecticut, Illinois, New Jersey, New York, and the Virgin Islands, cover public-sector

workers only.

Additional information on State Plans may be found at http://www.osha.gov/dcsp/osp/index.html.

For the most part, these OSHA-approved State Plans adopt standards that are identical to the federal OSHA

standards. However, some states have adopted state-specific standards that are at least as effective as the

Federal OSHA standards, including the New Jersey IAQ standard. The New Jersey IAQ standard, (N.J.A.C.

12:100-13; 2007) sets standards for indoor air quality in existing buildings occupied by public employees

during their regular working hours.

State of California IAQ Program. (http://www.cal-iaq.org/about-us/about-cal-iaq)

This program is a part of the California Department of Public Health (CDPH), separate from the State OSHA

program. The purpose of the California IAQ program is to conduct and promote the coordination of research,

investigations, experiments, demonstrations, surveys, and studies relating to the causes, effects, extent,

prevention, and control of indoor pollution in California.

National Consensus Standards

Note: These are NOT OSHA regulations. However, they do provide guidance from their originating

organizations related to worker protection.

American National Standards Institute (ANSI)/American Society of Heating, Refrigerating, and Air

Conditioning Engineers (ASHRAE).

• 62.1-2010, Ventilation for Acceptable Indoor Air Quality. This standard specifies recommended outdoor

air ventilation rates. The recommended outdoor ventilation rates are based on olfactory studies, and acceptable indoor air quality is met when 80% or more of the exposed people do not express dissatisfaction. Whereas ASHRAE Standard 62 has always been considered a design standard for ventilation,

building owner/operators should pay particular attention to Section 8 titled Operations and Maintenance.

Section 8 offers guidance to the building owner/operator as to what outdoor air ventilation components

should be maintained, what tasks should be performed, and the minimum frequency for performing

those tasks.

• 55-2010, Thermal Environmental Conditions for Human Occupancy. Specifies temperatures that

approximately 80 percent of building occupants should find acceptable.

American Society for Testing and Materials (ASTM).

• E1971–05, Standard Guide for Stewardship for the Cleaning of Commercial and Institutional Buildings.

1 0

Occupational Safety and

Health Administration
Consultation Services

Consultation assistance is available on request

to employers who want help in establishing and

maintaining a safe and healthful workplace. Largely

funded by OSHA, the service is provided at no cost

to the employer. Primarily developed for smaller

employers with more hazardous operations, the

consultation service is delivered by state governments employing professional safety and health

consultants. Comprehensive assistance includes an

appraisal of all mechanical systems, work practices,

and occupational safety and health hazards of the

workplace and all aspects of the employer’s present

job safety and health program. In addition, the

service offers assistance to employers in developing

and implementing an effective safety and health

program. No penalties are proposed or citations

issued for hazards identified by the consultant.

OSHA provides consultation assistance to the

employer with the assurance that his or her name

and firm and any information about the workplace

will not be routinely reported to OSHA enforcement

staff. For more information concerning consultation

assistance, see OSHA’s website at www.osha.gov.

Strategic Partnership Program

OSHA’s Strategic Partnership Program helps

encourage, assist and recognize the efforts of

partners to eliminate serious workplace hazards and

achieve a high level of worker safety and health.

Most strategic partnerships seek to have a broad

impact by building cooperative relationships with

groups of employers and workers. These partnerships are voluntary relationships between OSHA,

employers, worker representatives, and others (e.g.,

trade unions, trade and professional associations,

universities, and other government agencies).

For more information on this and other agency

programs, contact your nearest OSHA office, or visit

OSHA’s website at www.osha.gov.

OSHATraining and Education

OSHA area offices offer a variety of information

services, such as technical advice, publications,

audiovisual aids and speakers for special engagements. OSHA’s Training Institute in Arlington

Heights, IL, provides basic and advanced courses in

safety and health for Federal and state compliance

officers, state consultants, Federal agency personnel,

and private sector employers, workers and their

representatives.

The OSHA Training Institute also has established

OSHA Training Institute Education Centers to

OSHA Assistance

OSHA can provide extensive help through a variety

of programs, including technical assistance about

effective safety and health programs, state plans,

workplace consultations, and training and education.

Safety and Health Management

System Guidelines

Effective management of worker safety and health

protection is a decisive factor in reducing the extent

and severity of work-related injuries and illnesses

and their related costs. In fact, an effective safety

and health management system forms the basis of

good worker protection, can save time and money,

increase productivity and reduce employee injuries,

illnesses and related workers’ compensation costs.

To assist employers and workers in developing

effective safety and health management systems,

OSHA published recommended Safety and Health

Program Management Guidelines (54 Federal

Register (16): 3904-3916, January 26, 1989). These

voluntary guidelines can be applied to all places of

employment covered by OSHA.

The guidelines identify four general elements

critical to the development of a successful safety

and health management system:

• Management leadership and worker involvement,

• Worksite analysis,

• Hazard prevention and control, and

• Safety and health training.

The guidelines recommend specific actions,

under each of these general elements, to achieve

an effective safety and health management system.

The Federal Register notice is available online at

www.osha.gov.

State Programs

The Occupational Safety and Health Act of 1970

(OSH Act) encourages states to develop and operate

their own job safety and health plans. OSHA

approves and monitors these plans. Twenty-five

states, Puerto Rico and the Virgin Islands currently

operate approved state plans: 22 cover both private

and public (state and local government) employment; Connecticut, Illinois, New Jersey, New York

and the Virgin Islands cover the public sector only.

States and territories with their own OSHAapproved occupational safety and health plans must

adopt standards identical to, or at least as effective

as, the Federal OSHA standards.

I N D O O R A I R Q U A L I T Y I N C O M M E R C I A L A N D I N S T I T U T I O N A L B U I L D I N G S 1 1
OSHA Publications

OSHA has an extensive publications program.

For a listing of free items, visit OSHA’s website at

www.osha.gov or contact the OSHA Publications

Office, U.S. Department of Labor, 200 Constitution

Avenue, NW, N-3101, Washington, DC 20210;

telephone (202) 693-1888 or fax to (202) 693-2498.

Contacting OSHA

To report an emergency, file a complaint, or seek

OSHA advice, assistance, or products, call (800)

321-OSHA or contact your nearest OSHA Regional

or Area office listed at the end of this publication.

The teletypewriter (TTY) number is (877) 889-5627.

Written correspondence can be mailed to the

nearest OSHA Regional or Area Office listed at the

end of this publication or to OSHA’s national office

at: U.S. Department of Labor, Occupational Safety

and Health Administration, 200 Constitution Avenue,

N.W., Washington, DC 20210.

By visiting OSHA’s website at www.osha.gov,

you can also:

• File a complaint online,

• Submit general inquiries about workplace safety

and health electronically, and

• Find more information about OSHA and

occupational safety and health.

address the increased demand for its courses from

the private sector and from other federal agencies.

These centers are colleges, universities, and nonprofit organizations that have been selected after a

competition for participation in the program.

OSHA also provides funds to nonprofit

organizations, through grants, to conduct workplace

training and education in subjects where OSHA

believes there is a lack of workplace training.

Grants are awarded annually.

For more information on grants, training and

education, contact the OSHA Training Institute,

Directorate of Training and Education, 2020 South

Arlington Heights Road, Arlington Heights, IL 60005,

(847) 297-4810, or see Training on OSHA’s website

at www.osha.gov. For further information on any

OSHA program, contact your nearest OSHA regional

office listed at the end of this publication.

Information Available Electronically

OSHA has a variety of materials and tools available

on its website at www.osha.gov. These include

electronic tools, such as Safety and HealthTopics,

eTools, Expert Advisors; regulations, directives and

publications; videos and other information for

employers and workers. OSHA’s software programs

and eTools walk you through challenging safety and

health issues and common problems to find the

best solutions for your workplace.

1 2

Occupational Safety and

Health Administration
Region VII

Kansas City Regional Office

(IA*, KS, MO, NE)

Two Pershing Square Building

2300 Main Street, Suite 1010

Kansas City, MO 64108-2416

(816) 283-8745 (816) 283-0547 FAX

Region VIII

Denver Regional Office

(CO, MT, ND, SD, UT*, WY*)

1999 Broadway, Suite 1690

Denver, CO 80202-5716

(720) 264-6550 (720) 264-6585 FAX

Region IX

San Francisco Regional Office

(AZ*, CA*, HI*, NV*, and American Samoa,

Guam and the Northern Mariana Islands)

90 7th Street, Suite 18100

San Francisco, CA 94103

(415) 625-2547 (415) 625-2534 FAX

Region X

Seattle Regional Office

(AK*, ID, OR*, WA*)

1111 Third Avenue, Suite 715

Seattle, WA 98101-3212

(206) 553-5930 (206) 553-6499 FAX

*These states and territories operate their own

OSHA-approved job safety and health programs and

cover state and local government employees as

well as private sector employees. The Connecticut,

Illinois, New Jersey, New York and Virgin Islands

plans cover public employees only. States with approved programs must have standards that are

identical to, or at least as effective as, the Federal

OSHA standards.

Note: To get contact information for OSHA Area

Offices, OSHA-approved State Plans and OSHA

Consultation Projects, please visit us online at

www.osha.gov or call us at 1-800-321-OSHA.

OSHA Regional Offices

Region I

Boston Regional Office

(CT*, ME, MA, NH, RI, VT*)

JFK Federal Building, Room E340

Boston, MA 02203

(617) 565-9860 (617) 565-9827 FAX

Region II

New York Regional Office

(NJ*, NY*, PR*, VI*)

201 Varick Street, Room 670

New York, NY 10014

(212) 337-2378 (212) 337-2371 FAX

Region III

Philadelphia Regional Office

(DE, DC, MD*, PA, VA*, WV)

The Curtis Center

170 S. Independence Mall West

Suite 740 West

Philadelphia, PA 19106-3309

(215) 861-4900 (215) 861-4904 FAX

Region IV

Atlanta Regional Office

(AL, FL, GA, KY*, MS, NC*, SC*, TN*)

61 Forsyth Street, SW, Room 6T50

Atlanta, GA 30303

(678) 237-0400 (678) 237-0447 FAX

Region V

Chicago Regional Office

(IL*, IN*, MI*, MN*, OH, WI)

230 South Dearborn Street

Room 3244

Chicago, IL 60604

(312) 353-2220 (312) 353-7774 FAX

Region VI

Dallas Regional Office

(AR, LA, NM*, OK, TX)

525 Griffin Street, Room 602

Dallas, TX 75202

(972) 850-4145 (972) 850-4149 FAX

(972) 850-4150 FSO FAX

I N D O O R A I R Q U A L I T Y I N C O M M E R C I A L A N D I N S T I T U T I O N A L B U I L D I N G S 1 3
Carbon dioxide (CO2)

CO2 is a colorless, odorless, and tasteless gas (36). It

is a product of completed carbon combustion and

the by-product of biological respiration. ASHRAE

states that CO2 concentrations in acceptable outdoor

air typically range from 300-500 ppm. Adverse

health effects from CO2 may occur since it is an

asphyxiant gas. At concentrations above 15,000

ppm, some loss of mental acuity has been noted

(36). The OSHA PEL is 5,000 ppm as an 8-hour TWA.

The CO2 levels can be used as a rough indicator of

the effectiveness of ventilation (26), and excessive

population density in a structure. CO2 increases in

buildings with higher occupant densities, and is

diluted and removed from buildings based on

outdoor air ventilation rates. Therefore, examining

levels of CO2 in indoor air can reveal information

regarding occupant densities and outdoor air

ventilation rates. High CO2 levels may indicate a

problem with overcrowding or inadequate outdoor

air ventilation rates.

Carbon Dioxide Poisoning – Symptoms

CO2, a by-product of normal cell function, is

removed from the body via the lungs in the exhaled

air. Exposure to high levels of CO2 can increase the

amount of this gas in the blood, which is referred to

as hypercapnia or hypercarbia. As the severity of

hypercapnia increases, more symptoms ranging

from headache to unconsciousness appear, and it

can also lead to death (36, 37).

Pesticides

Pesticides are any substances or mixture of

substances used for preventing, destroying,

repelling, or mitigating any pest. These substances

include insecticides, herbicides, fungicides, and

various other substances used to control pests.

Pesticides can cause harm to humans, animals, and

the environment because they are designed to kill

or otherwise adversely affect living organisms.

Pesticides can also kill potential disease-causing

organisms (8, 38).

Pesticide Poisoning Symptoms

Symptoms of pesticide poisoning depend heavily

on the pesticide to which the worker was exposed.

Symptoms often appear within minutes of pesticide

exposure, but may take much longer to develop.

The most common symptoms include headache,

tears in the eyes, vomiting, sweating, and general

weakness. Exposure to high doses may cause

seizures and death.

Appendix A: Common Indoor

Air Contaminants

The purpose of this section is to provide additional

information about several common indoor air

contaminants.

Carbon monoxide (CO)

CO is a colorless, odorless gas produced by the

incomplete burning of material containing carbon.

CO poisoning2 can cause brain damage and death.

Common sources of CO are leaking vented

combustion appliances, automobile exhaust,

parking garages, etc. When not properly ventilated,

emitted CO can build up. Employees exposed to

low levels of CO may feel sick with headache and

nausea, and will feel better when exposed to fresh

air outside. However, their symptoms will recur

shortly after returning to their workplace if CO is

not eliminated.

CO Poisoning Symptoms

Poisoning due to low levels of CO can be confused

with influenza symptoms, food poisoning, or other

illnesses, and can be a long-term health risk if left

unattended. Some of the symptoms of low-level CO

poisoning are shortness of breath, mild nausea, and

mild headaches (30-35).

Prolonged exposure to high levels of CO can lead to

brain damage and even death. Adequate ventilation

is an important control measure. The OSHA

Permissible Exposure Limit (PEL) for CO is 50 parts

per million (ppm) as an 8-hour time-weighted average (TWA); the National Institute for Occupational

Safety and Health has a Recommended Exposure

Limit (REL) of 35 ppm as a 10-hour TWA. According

to the American Conference of Governmental

Industrial Hygienists (ACGIH), the threshold limit

value for CO is 25 ppm as an 8-hour TWA.

Carbon Monoxide Detectors

In addition to having a professional inspect

appliances and furnaces, commercially available

carbon monoxide detectors can be used to monitor

the levels of carbon monoxide in buildings throughout the year. The manufacturer’s instructions on

placement and maintenance should be followed.

1 4

Occupational Safety and

Health Administration

2CO is a chemical asphyxiant; it displaces O2 in the blood,

thereby suffocating the person exposed.
Small dust particles may remain airborne for long

periods, while large particles settle more quickly.

However, particles that have settled may be easily

resuspended in the ambient air by currents of air or

other disturbances. Drapery, carpet and other places

where dust collects can harbor these contaminants;

dirty cooling coils, humidifiers, condensate drains,

and ductwork can incubate bacteria and molds.

Areas with high humidity can accelerate their

growth.

The most common sources of biological air

contaminants are moisture-laden areas that support

the growth of mold and bacteria present in the air

(8, 16, 19, 44). Also, wet surfaces can provide a

breeding ground for insects such as dust mites.

Moisture-induced microbial growth can result from

water leaks and/or by condensation due to high

humidity. Persistent dampness and microbial

growth on interior surfaces and in building

structures should be avoided or minimized as they

may lead to adverse health effects (15). Common

sources of moisture in buildings include: plumbing;

roof and window leaks; flooding; condensation on

cold surfaces, e.g., pipe sweating; poorly maintained

drain pans; and wet foundations caused by landscaping or gutters that direct water into or under the

building. Water vapor from unvented or poorly

vented kitchens, showers, combustion appliances,

or steam pipes can also create conditions that

promote microbial growth. The most effective

means to prevent or minimize adverse health effects

is to determine the sources of persistent dampness

in the workplace and eliminate them. Also, strict

adherence to a housekeeping schedule and use of

HEPA-filtered vacuum cleaners will help reduce

ambient levels of allergens.

Damp Indoor Environments

Damp indoor environments have been associated

with many serious health effects, including asthma,

hypersensitivity, and sinusitis. Moisture incursion

leading to dampness can result from water leaks

and/or by condensation due to high humidity.

Common sources of moisture in buildings include:

plumbing; roof and window leaks; flooding;

condensation on cold surfaces, e.g., pipe sweating;

poorly-maintained drain pans; and wet foundations

due to landscaping or gutters that direct water into

or under the building. Water vapor from unvented

or poorly-vented kitchens, showers, combustion

appliances, or steam pipes can also create

conditions that promote microbial growth.

Steps to Reduce Exposure

Integrated Pest Management Principles should

always be implemented. Pesticide products should

be used according to application and ventilation

instructions provided by the manufacturer. In

addition:

• Mix or dilute pesticides outdoors;

• Increase ventilation when using pesticides;

• Use non-chemical methods of pest control when

possible;

• Do not store unneeded pesticides;

• Dispose of unwanted containers safely; and

• Keep indoor spaces clean, dry, and well ventilated to avoid pest problems.

Radon

Radon is a colorless, odorless, and tasteless

radioactive gas (6, 13, 17, 39, 40). It comes from the

natural decay of uranium and some other radionuclides that are present in soil. Radon is responsible

for most of the public’s exposure to ionizing radiation (39, 40). It is often the single largest contributor

to an individual's background radiation dose, and

levels can vary widely from location to location.

Radon gas can accumulate in buildings, especially

in confined areas such as attics and basements.

Radon penetrates cracks and drain openings in

foundations, basements, and crawl spaces. Some

building materials will also release radon into the

air. It can also be found in some spring waters and

hot springs, where it can be released into the air

when the water is drawn for use indoors. Exposure

to radon may cause lung cancer in humans.

The EPA recommends taking actions to reduce

radon exposure if levels exceed four picocuries per

liter of air (4 pCi/L) (25). Active soil depressurization

and building ventilation are the two most commonly

used strategies for controlling radon in buildings.

Radon reduction methods include sealing concrete

slab floors, basement foundations, and water

drainage systems, and increasing ventilation.

These techniques are usually cost-effective, and

can greatly reduce or eliminate contamination and

the associated health risks.

Biological Contaminants

Animals, plants, and microbes are sources of air

pollutants. Dander from animals, pollens from

plants, and microbes, may act as allergens when

they are inhaled. These biological contaminants are

usually attached to dust particles of various sizes.

I N D O O R A I R Q U A L I T Y I N C O M M E R C I A L A N D I N S T I T U T I O N A L B U I L D I N G S 1 5
Volatile Organic Compounds (VOCs)

VOCs refer to organic chemical compounds that

have significant vapor pressures, and that can

adversely affect the environment and human health.

VOCs are emitted as vapors from certain solids or

liquids, and include a variety of chemicals, some of

which may have short- and long-term adverse

health effects (17, 45, 46). Concentrations of many

VOCs are consistently higher indoors (up to ten

times higher) than outdoors. VOCs are emitted by a

wide array of products numbering in the thousands.

Examples include paints and lacquers, paint

strippers, cleaning supplies, pesticides, building

materials and furnishings, office equipment such as

copiers and printers, correction fluids and carbonless copy paper, and graphics and craft materials,

including glues and adhesives, permanent markers,

and photographic solutions (8). More commonly

known VOCs include benzene, formaldehyde,

methylene chloride, trichloroethylene, and tetrachloroethylene (13). Exposure to VOCs can result in

both acute and chronic health effects, depending on

many factors such as the level of exposure and the

length of exposure. A few VOCs, such as benzene,

have been directly linked to cancer in humans, and

others are suspected of causing cancer.

Since people today spend most of their time at

home or in an office, long-term exposure to VOCs in

the indoor environment can contribute to IAQ related problems (31). In offices, VOCs result from

new furnishings, wall coverings, and office equipment such as photocopy machines, which can offgas VOCs into the air (47, 48). Good ventilation and

air-conditioning systems are essential to reduce

VOC emissions in the indoor environment (47).

Steps to Reduce Exposure

(http://www.epa.gov/iaq/voc.html)

• Use products according to manufacturer’s

directions.

• Make sure that plenty of fresh air is provided

when using these products.

• Discard used containers safely.

• Buy quantities that can be used in short periods

of time.

Well-designed, -constructed and –maintained

building envelopes are critical to the prevention and

control of excess moisture and microbial growth by

avoiding thermal bridges and preventing intrusion

by liquid or vapor-phase water. Management of

moisture requires proper control of temperatures

and ventilation to avoid high humidity, condensation

on surfaces, and excess moisture in materials.

Ventilation should be distributed effectively in spaces,

and stagnant air zones should be avoided (5, 8).

ASHRAE recommends relative humidity levels

between 30 and 60 percent for optimum comfort

(25). Higher humidity may result in microbial

growth. A consistently implemented good-housekeeping plan is essential to eliminate or reduce the

microbial growth in the building.

Legionella

Legionellosis or Legionnaires’ Disease is caused by

a waterborne bacterium, Legionella, which grows

best in slow-moving, or still warm water (42-44).

The primary route of exposure is aerosolization,

most commonly from domestic hot-water systems

(e.g., showers, sprays, etc.). Mist from evaporative

cooling towers without biocide treatment is another

reported source. Outbreaks in medical facilities can

occur because the patients often have weak or

suppressed immune systems.

For cooling towers and evaporative condensers,

prevention efforts center on improving the location

and maintenance of the cooling towers to limit the

growth and spread of Legionella bacteria. These

devices should be inspected and thoroughly cleaned

at least once a year. Corroded parts, such as drift

eliminators, should be replaced, and algae and

accumulated scale should be removed. Cooling

water should be treated constantly with antimicrobial agents. Ideally, an automatic water-treatment

system should be used that continuously controls

the quality of the circulating water.

For domestic hot-water systems, prevention efforts

focus on controlling water temperature, avoiding

dead-legs, avoiding stagnation, and cleaning

storage tanks to limit the growth and spread of

Legionella bacteria.

1 6

Occupational Safety and

Health Administration
Appendix B: Steps to

Improve Indoor Air Quality3

What employers can do

• Maintain a good working relationship with

building management on indoor environmental

issues.

• Place office furniture and equipment in locations

based on the adequate air circulation, temperature control, and pollutant removal functions of

the HVAC system.

• Coordinate with building management when

responsibility for design, operation, and

maintenance of the ventilation system is shared.

• Avoid procedures and products that can cause

IAQ problems.

• Integrate IAQ concerns into purchasing

decisions.

• Work with the building manager to ensure use

of only necessary and appropriate pest-control

practices; use nonchemical methods when

possible.

• Work with building management and the

contractor before starting to remodel or renovate

to identify ways of minimizing building-occupant

exposure, and to ensure that the air-distribution

system is not disrupted.

• Encourage building management to develop a

preventive IAQ management program following

guidance issued by the EPA and the National

Institute for Occupational Safety and Health.

I N D O O R A I R Q U A L I T Y I N C O M M E R C I A L A N D I N S T I T U T I O N A L B U I L D I N G S 1 7

3See Item 29 in the last section of this document titled

“References.”

What workers can do

• Do not block air vents or grilles.

• Water and maintain office plants properly.

• Dispose of garbage promptly and properly.

• Store food properly.

• Avoid bringing products into the building that

could release harmful or bothersome odors or

contaminants.

• Notify the building or facility manager

immediately if you suspect an IAQ problem.
Duct and Plenum equipment

■ Written inspection and maintenance program.

■ Supply, exhaust, return grilles, and ducts clear

and clean.

■ Routine inspection of ducts, debris, and microbial

growth (e.g., semi-annually).

■ Provisions of cleanout (e.g., within four feet

downstream of duct expansions, supply air

openings, or where particulate deposition may

occur).

■ Ductwork attached, not dented.

■ Insulation intact, not wet, and no microbial

growth.

■ Ductwork properly balanced.

Filtration systems

■ Written maintenance, operating, and inspection

programs.

■ Routine inspection.

■ Provision for measuring pressure drops across

the filtration system.

1 8

Occupational Safety and 

Health Administration

Appendix C: HVAC System

Maintenance Checklist4

The following checklist can be used to investigate

the HVAC system to make sure it is operating 

properly (e.g., the right mix of fresh air, proper 

distribution, and filtration systems are working, etc.)

Cooling Towers

■ Written maintenance and inspection program.

■ Operated in accordance with manufacturer 

specifications.

■ Inspected regularly (monthly, or as required).

■ Treatment of waste to control microorganisms,

as required.

■ Recordkeeping of biocide use – brand, volume,

and results.

■ Training of workers for hazards involved.

Humidifiers

■ Written maintenance and inspection program.

■ Inspected weekly during operation.

■ Cleaned and disinfected as required.

■ No visual buildup of mold or slime.

■ Disinfectants removed before reactivating 

humidifiers.

Cooling Coils

■ Written maintenance and inspection program.

■ Monthly (or, as required) inspections during 

operation.

■ Removal of dirt, slime, and mold, as required.

■ Upstream filters operating properly.

Drain Pans, drainage systems

■ Written maintenance and inspection program.

■ Monthly inspection (or, as required).

■ Drains maintained in free-flowing condition.

■ No accumulation of stagnant water.

■ No buildup of slime, mold, or dirt.

■ Removal of dirt, slime, and mold, as required.

■ Sample water for microbes, as required.

4See Items 24 and 37 in the last section of this document titled

“References.”
Appendix D: Investigating

IAQ Problems and 

Complaints

Identifying the cause(s) of IAQ problems and 

complaints may be difficult if an obvious source is

not evident. Investigating unclear IAQ problems

should take into account patterns and factors, such

as occupant complaints and symptoms, location(s)

in the building, time of day, seasonal differences,

and relationship to activities inside or outside the

building. Below are suggestions of information that

may be helpful to collect. 

Once information is gathered, it should then be 

analyzed for patterns and possible causes of the 

IAQ problem. The analysis may point to specific 

methods, such as those discussed on page 7 

(Identification and Assessment). The next step is to

fix problems identified and evaluate the results. 

Has the fix resolved the problems or complaints? 

If not, then further investigation will need to be 

pursued. Consultation with safety and health 

professionals or other experts should be considered

at any point during an IAQ investigation.

Information that may be helpful in IAQ 

investigations:

General office conditions:

• Housekeeping

• How often is the office vacuumed? 

• How often are carpet and drapes shampooed?

• How often are floors waxed?

• Are there any visible signs of dust?

• Have pesticides been applied recently?

• Is there any evidence of moisture intrusion into

the building?

Air quality in the office:

• Odor

• Dry

• Humid

• Dusty

• Warm

• Cool

• Drafts

• Temperature fluctuation

• Within office

• Between offices

• Between floors

• Any recent changes in:

• Work space

• General office

• Building

• New equipment added to the office

When occupant complaints are related to symptoms

or health problems, medical evaluation may be 

required. Persons with respiratory diagnoses that

may be caused or exacerbated by workplace 

exposures should discuss these with their treating

physician, and treating physicians may access 

additional expertise through the network of National

Institute for Occupational Safety and Health

(NIOSH)-funded Education and Research Centers, 

or through the member clinics of the not-for-profit 

Association of Occupational and Environmental

Clinics. Workers’ compensation systems differ by

states, but may also be available to support medical

care for work-related diseases. 

EPA and NIOSH have published two excellent 

resources to screen and investigate IAQ problems.

The first, published in 1991, is Building Air Quality:

A Guide for Building Owners and Facility Managers

(http://www.cdc.gov/niosh/baqtoc.html). Chapter 6-

“Diagnosing IAQ Problems” provides a systematic

approach and includes tools, such as logs, questionnaires, diaries, and checklists. The second, published by EPA and NIOSH in 2002, is a companion

document that updates and expands on the 1991

publication. The 2002 publication, Indoor Air Quality

Education and Assessment Model (I-BEAM)

(http://www.epa.gov/iaq/largebldgs/i-beam/index.html),

is separated into modules, and includes online 

interactive examples of problems and solutions.

I N D O O R A I R Q U A L I T Y I N C O M M E R C I A L A N D I N S T I T U T I O N A L B U I L D I N G S 1 9
Appendix E: Selected Resources

Hazard Recognition

IAQ problems can be caused by improperly operated and maintained HVAC systems, overcrowding, 

microbiological contamination, outside air pollutants, and off-gassing from materials in the office and 

mechanical equipment. Related problems also may include discomfort problems due to improper 

temperature and relative humidity conditions.

The following references aid in recognizing IAQ hazards in the workplace:

• OSHA Technical Manual. OSHA Directive TED 01-00-015 [TED 1-0.15A] (1999, January 20).

https://www.osha.gov/dts/osta/otm/otm_toc.html

• Indoor Air Quality Investigation. Contains guidelines for IAQ investigations, recommendations on 

sampling instrumentation and methods, as well as guidelines for employers to prevent or alleviate IAQ

problems. https://www.osha.gov/dts/osta/otm/otm_iii/otm_iii_2.html

• Carbon Monoxide Poisoning. OSHA Fact Sheet (2002) .

http://www.osha.gov/OshDoc/data_General_Facts/carbonmonoxide-factsheet.pdf 

• Mold. OSHA Safety and Health Topics Page. https://www.osha.gov/SLTC/molds/index.html

• Stachybotrys Chartarum. OSHA Safety and Health Topics Page. 

https://www.osha.gov/dts/chemicalsampling/data/CH_267785.html#General

• Indoor Environmental Quality. National Institute for Occupational Safety and Health (NIOSH) Safety and

Health Topic Page. Links to several other NIOSH publications, including the NIOSH fact sheet on IEQ.

http://www.cdc.gov/niosh/topics/indoorenv

• Preventing Carbon Monoxide Poisoning from Small Gasoline-Powered Engines and Tools. U.S. 

Department of Health and Human Services, National Institute for Occupational Safety and Health 

Publication No. 96-118, (1996). Gives examples of the many situations in which people have been 

poisoned because they did not recognize the danger of using small gasoline-powered engines indoors.

These poisonings can occur quickly, even in the presence of what many would consider “adequate 

ventilation,” and in areas that many would define as relatively open spaces, such as parking garages.

http://www.cdc.gov/niosh/carbon2.html

• Fact Sheet: Ventilation and Air Quality in Offices. Environmental Protection Agency. Gives an overview

of sources of indoor air pollution, health problems and ventilation, control, ventilation standards and

building codes, ventilation system problems and solutions, air cleaners, economic considerations, and

resolving air-quality problems. http://www.epa.gov/iedweb00/pubs/ventilat.htm

• Air - Indoor Air Quality (IAQ). Environmental Protection Agency. Contains an introduction to IAQ, a listing

of common pollutants, and references to IAQ publications, hotlines, and links.

http://www.epa.gov/iaq/pubs

• Mold Remediation in Schools and Commercial Buildings. March 2001. Presents guidelines for the 

investigation, evaluation, and remediation/cleanup of mold and moisture problems in schools and 

commercial buildings. http://www.epa.gov/iaq/molds/mold_remediation.html

• An Office Building Occupant’s Guide to Indoor Air Quality. Describes factors that contribute to indoor air

quality and comfort problems, and the roles of building managers and occupants in maintaining a good

indoor environment. http://www.epa.gov/iaq/pubs/occupgd.html

• The Inside Story: A Guide to Indoor Air Quality. Office of Radiation and Indoor Air, U.S. Consumer 

Product Safety Commission. April 1995. Provides a comprehensive online booklet on IAQ concerns in

homes. http://www.epa.gov/iaq/pubs/insidest.html

• IAQ Resources. Provides a listing of various hotlines and resources related to IAQ.

http://www.epa.gov/iaq/iaqinfo.html

2 0

Occupational Safety and 

Health Administration
• Guidelines on Assessment and Remediation of Fungi in Indoor Environments. New York City Department

of Health. Addresses mold contamination of building components (walls, ventilation systems, support

beams, etc.) that are chronically moist or water damaged. 

http://www.nyc.gov/html/doh/html/epi/moldrpt1.shtml

• Indoor Air Quality Publications. Consumer Product Safety Commission (CPSC). Contains an index of

CPSC publications related to IAQ. http://www.cpsc.gov/cpscpub/pubs/iaq.html

Evaluation and Control

Methods used in an IAQ investigation may include: identification of pollutant sources; evaluation of 

HVAC system performance; observation of production processes and work practices; measurement of 

contamination levels and employee exposure; medical testing or physical examinations; employee 

interviews; and review of records of medical tests, job histories, and injuries and illnesses.

The following resources provide information about evaluating and controlling IAQ in the workplace.

Evaluation

• Volatile Organic Compounds in Air. OSHA Method PV2120. May 2003.

https://www.osha.gov/dts/sltc/methods/partial/pv2120/pv2120.html

• Ozone in Workplace Atmospheres (Impregnated Glass Fiber Filter). OSHA Method ID-214. March 1995.

https://www.osha.gov/dts/sltc/methods/inorganic/id214/id214.html 

• Carbon Monoxide in Workplace Atmospheres (Direct-Reading Monitor). OSHA Method ID-209. March

1993. https://www.osha.gov/dts/sltc/methods/inorganic/id209/id209.html

• Sulfur Dioxide in Workplace Atmospheres (Impregnated Activated Beaded Carbon). OSHA Method 

ID-200. April 1992. https://www.osha.gov/dts/sltc/methods/inorganic/id200/id200.html

• Carbon Monoxide in Workplace Atmospheres. OSHA Method ID-210. March 1991.

https://www.osha.gov/dts/sltc/methods/inorganic/id210/id210.html

• Formaldehyde in Workplace Atmospheres (3M Model 3721 Monitor). OSHA Method ID-205. 

December 1990. https://www.osha.gov/dts/sltc/methods/inorganic/id205/id205.html

• Carbon Dioxide in Workplace Atmospheres. OSHA Method ID-179. June 1987.

https://www.osha.gov/dts/sltc/methods/inorganic/id172/id172.html

• For additional information, see OSHA's Safety and Health Topics Pages on:

- Formaldehyde https://www.osha.gov/SLTC/formaldehyde/index.html

- Hazardous and Toxic Substances https://www.osha.gov/SLTC/hazardoustoxicsubstances/index.html

- Legionnaires’ Disease https://www.osha.gov/SLTC/legionnairesdisease/index.html

- Sampling and Analysis https://www.osha.gov/SLTC/samplinganalysis/index.html

- Styrene https://www.osha.gov/SLTC/styrene/index.html

• EPA: IAQ Tools for Schools Action Kit. http://www.epa.gov/iaq/schools/actionkit.html

• The National Institute for Occupational Safety and Health (NIOSH), through its Health Hazard Evaluation

(HHE) Program, responds to requests from employers, employees and their representatives, and 

government agencies. NIOSH conducts workplace assessments to determine if workers are exposed to

hazardous materials or harmful conditions, and whether these exposures are affecting workers’ health.

NIOSH has conducted more than 200 IAQ-related HHEs. Recent reports can be found on NIOSH’s Indoor

Environmental Quality website at http://www.cdc.gov/niosh/topics/indoorenv

• Department of Energy. Guide to Operating and Maintaining EnergySmart Schools. Building Technology

Program. U.S. Department of Energy. Office of Energy Efficiency and Renewable Energy.

http://apps1.eere.energy.gov/buildings/publications/pdfs/energysmartschools/ess_o-and-m-guide.pdf

• GSA 2003 Facilities Standards (P100) Overview. Environmental Policies & Practices.

http://www.gsa.gov/portal/content/101230

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• U.S. Green Building Council LEED for Existing Buildings. Leadership in Environmental and 

Energy Design for Existing Buildings. http://www.usgbc.org/DisplayPage.aspx?CMSPageID=221#v2008

Control 

• A Brief Guide to Mold in the Workplace. OSHA Safety and Health Information Bulletin. October 10, 2003.

https://www.osha.gov/dts/shib/shib101003.html

• Ventilation. OSHA Safety and Health Topics Page. https://www.osha.gov/SLTC/ventilation/index.html

• Building Air Quality: A Guide for Building Owners and Facility Managers. U.S. Department of Health and

Human Services, National Institute for Occupational Safety and Health (NIOSH) Publication No. 91-114.

Also, referenced as Environmental Protection Agency (EPA) Publication No. 400/1-91/003. December

1991. http://www.cdc.gov/niosh/baqtoc.html

• Building Air Quality: Action Plan. Publication No. 98-123. Also, referenced as EPA Publication No. 

402-K-98-001. June 1998. Provides an 8-step building air-quality action plan for building owners and

managers to be used with NIOSH Publication No. 91-114 and EPA Publication No. 400/1-91/033.

http://www.cdc.gov/niosh/98-123a.html

2 2

Occupational Safety and 

Health Administration
Appendix F: OSHASponsored Environmental 

Tobacco Smoke Workshops

Workshop I

Workshop Summary: Assessing Exposure to 

Environmental Tobacco Smoke in the Workplace.

Jonathan M. Samet. Environmental Health 

Perspectives Supplements, vol. 107, no. S2, May

1999.

Environmental tobacco smoke (ETS) is a term now

widely used to refer to the mixture of sidestream

smoke and exhaled mainstream smoke that pollutes

air in locations where tobacco smoking is taking

place. A multidisciplinary workshop was convened

to address key issues related to ETS exposure in the

workplace in order to prepare the groundwork for a

risk assessment of the hazard ETS poses to workers.

Workshop participants concluded that substantial

evidence was now available on worker exposure to

ETS using both direct and indirect approaches to 

exposure assessment, and that these data could be

used to project distribution of exposures to ETS in

the nation's workplaces. This summary of the 

discussions at the workshop is an overview of the

suggested approach to exposure assessment.

http://ehpnet1.niehs.nih.gov/docs/1999/Suppl-2/309-312samet/abstract.html

I N D O O R A I R Q U A L I T Y I N C O M M E R C I A L A N D I N S T I T U T I O N A L B U I L D I N G S 2 3

Workshop II

OSHA/ACGIH® Environmental Tobacco Smoke Workshop Proceedings, Publication #99-078

Proceedings of the OSHA/ACGIH® Environmental

Tobacco Smoke Workshop held June 6, 1998, in

Cincinnati, OH. The workshop brought together a

panel of ventilation experts, along with hospitality

industry managers and design engineers, to discuss

effective and non-effective ventilation strategies for

smoking sections in restaurants and bars. 

Workshop III

Workshop Summary: Workshop on Health Risks 

Attributable to ETS Exposure in the Workplace.

Maritta S. Jaakkola and Jonathan M. Samet (Johns

Hopkins University, Baltimore, Maryland, USA). 

Environmental Health Perspectives, vol. 107, supp.

6, December 1999.

This 1998 workshop was convened to address the

health risks of exposure to environmental tobacco

smoke (ETS) in the workplace. It was paired with a

1997 workshop on issues related to ETS exposure in

work environments. The 1998 workshop involved a

multidisciplinary group of participants who reviewed evidence on the quantitative risks to health

posed by ETS and discussed the development of

risk assessment methodology for the future. 
2 4

Occupational Safety and 

Health Administration

References

1. U.S. EPA. An Office Building Occupant's Guide to Indoor Air Quality. 

http://www.epa.gov/iaq/pubs/occupgd.html

2. U.S. EPA. Indoor Air Quality. The Inside Story: A Guide to Indoor Air Quality.

http://www.epa.gov/iaq/pubs/insidest.html

3. CDC. Healthy Housing Reference Manual. Chapter 5: Indoor Air Pollutants and Toxic Materials.

http://www.cdc.gov/nceh/publications/books/housing/cha05.html

4. NIOSH Recommendations for the Cleaning and Remediation of Flood-Contaminated HVAC Systems: A

Guide for Building Owners and Managers. http://www.cdc.gov/niosh/topics/emres/Cleaning-Flood-HVAC.html

5. American Society of Heating, Refrigerating and Air-Conditioning Engineers (ASHRAE) (2010). ASHRAE

Standard 62.1. Ventilation for Acceptable Indoor Air Quality. Atlanta, GA.

6. Fisk, W.J. (2000). Health and Productivity Gains from Better Indoor Air Environments and Their Relationship with Building Energy Efficiency. Annual Review of Energy and the Environment, 25: 537-566.

7. Spengler, J. D., Samet, J. M., and McCarthy, J. F. (2001). Indoor Air Quality Handbook. McGraw-Hill.

8. U.S. EPA. An Introduction to Indoor Air Quality (IAQ). 

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9. American Thoracic Society. Environmental Controls and Lung Disease. American Review of 

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10. American Lung Association. Health Effects and Sources of Indoor Air Pollution, Parts I and II, 1989,

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Report 10. Effects of Indoor Air Pollution on Human Health (1991).

12. U.S. EPA. Indoor Air Pollution: An Introduction for Health Professionals. (Last updated April 28, 2010).

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13. Bernstein, J. A., Alexis, N., Bacchus, H., Bernstein, I. L., Fritiz, P., et al. (2008). The Health Effects of 

Nonindustrial Indoor Air Pollution. Journal of Allergy and Immunology, 12(3): 585-590.

14. Stapczynski, J.S., 2004. Chapter 62: Respiratory Distress. Tintinalli, J.E., Kelen, G.D., Stapczynski, J.S.,

Ma, O.J., and Cline, D.M. Tintinalli’s Emergency Medicine, 6th Edition.

15. WHO. 2009 WHO Guidelines for Indoor Air Quality – Dampness and Mold. 

http://katysexposure.wordpress.com/2009/07/19/2009-who-guidelines-for-indoor-air-quality-dampness-and-mold-2

16. CDC Online Source for Credible Health Information: Mold. http://www.cdc.gov/mold

17. OSHA. Preventing Mold-Related Problems in the Indoor Workplace. OSHA 3304-04N 2006.

http://www.osha.gov/Publications/preventing_mold.pdf

18. CDC. Healthy Housing Reference Manual. Chapter 5, Indoor Air Pollutants and Toxic Materials.

http://www.cdc.gov/nceh/publications/books/housing/cha05.html

19. U.S. EPA. IAQ Building Education and Assessment Model (I-BEAM): TIA Maintenance and 

Housekeeping Programs. 

http://www.epa.gov/iaq/largebldgs/i-beam/text/maintenance_and_housekeeping.html#IAQ%20Housekeeping%20Tasks

20. OSHA. A Brief Guide to Mold in the Workplace. OSHA Safety and Health Information Bulletin, October

10, 2003. http://www.osha.gov/dts/shib/shib101003.html

21. Institute of Medicine (IOM) (2004). Damp Indoor Spaces and Health. Washington, DC: National 

Academy of Sciences.

22. Fisk, W. J., Lei-Gomez, Q., Mendell, M. J. (2007). Meta-analysis of the Associations of Respiratory

Health Effects with Dampness and Mold in Homes. Indoor Air 17(4):284-296.

23. World Health Organization (WHO) (2009). WHO Guidelines for Indoor Air Quality: Dampness and

Mould. WHO Regional Office for Europe.

http://www.euro.who.int/__data/assets/pdf_file/0017/43325/E92645.pdf
24. U.S. EPA. Indoor Air Quality. Tools for Schools Action Kit IAQ Coordinator’s Guide: A Guide to 

Implementing an IAQ Program. http://www.epa.gov/iaq/schools/tools4s2.html

25. ASHRAE Standard 55 (2010). Thermal Environmental Conditions for Human Occupancy.

26. ASTM Standard D-6245-98. Using Indoor Carbon Dioxide Concentrations to Evaluate Indoor Air 

Quality and Ventilation.

27. U.S. Consumer Product Safety Commission. Tips for Purchasing and Installing New Carpet. 

CPSC Document #454. http://www.cpsc.gov/cpscpub/pubs/454.html

28. Carpet and Rug Institute (1999). Carpet and Indoor Air Quality Technical Bulletin. 

http://www.carpet-rug.org/technical_bulletins/9902_Carpet_and_IAQ.pdf

29. NIOSH. Building Air Quality: Action Plan. http://www.cdc.gov/niosh/baqact4.html

30. U.S. Consumer Product Safety Commission. The Senseless Killer. 1993 GAO Publication 

No. 1993-0-356-764.

31. Mott, J. A., Wolfe, M. I., Alverson, C. J., Macdonald, S. C., Baily, C. R., Ball, L. B., et al. (2002). National

Vehicle Emissions Policies and Practices and Declining U.S. Carbon Monoxide Mortality. JAMA, 288:

988-995.

32. American Lung Association. Carbon Monoxide Indoors. 

http://www.lungusa.org/healthy-air/home/resources/carbon-monoxide-indoors.html

33. U.S. EPA. An Introduction to Indoor Air Quality: Carbon Monoxide. http://www.epa.gov/iaq/co.html

34. OSHA. Carbon Monoxide Poisoning. Fact Sheet, 2002. 2 pages.

http://www.osha.gov/OshDoc/data_General_Facts/carbonmonoxide-factsheet.pdf

35. OSHA. Carbon Monoxide in Workplace Atmospheres. OSHA Method ID-210, March 1991.

http://www.osha.gov/dts/sltc/methods/inorganic/id210/id210.html

36. Health Canada. Indoor Air Quality in Office Buildings. Carbon Dioxide. 

http://www.hc-sc.gc.ca/ewh-semt/pubs/air/office_building-immeubles_bureaux/co2-eng.php

37. Canadian Centre for Occupational Health and Safety. Health Effects of Carbon Dioxide Gas.

http://www.ccohs.ca/oshanswers/chemicals/chem_profiles/carbon_dioxide/health_cd.html

38. U.S. EPA. An Introduction to Indoor Air Quality: Pesticide. http://www.epa.gov/iaq/pesticid.html

39. U.S. EPA. A Citizen’s Guide to Radon. The Guide to Protecting Yourself and Your Family from Radon.

EPA 402/K-09/001. January 2009. http://www.epa.gov/radon

40. Agency for Toxic Substances and Disease Registry (ATSDR). Radon. September 2008. 

CAS ID #: 14859-67-7. http://www.atsdr.cdc.gov/substances/toxsubstance.asp?toxid=71 

41. OSHA. Mold. Safety and Health Topics Page. http://www.osha.gov/SLTC/molds/index.html

42. Canadian Centre for Occupational Health and Safety. Legionnaires Disease. 

http://www.ccohs.ca/oshanswers/diseases/legion.html

43. CDC. Legionellosis Resource Site (Legionnaires’ Disease and Pontiac Fever). Patient Facts: Learn More

about Legionnaires’ disease. http://www.cdc.gov/Legionella/patient_facts.html

44. OSHA. Legionnaires’ Disease. Safety and Health Topics Page. 

http://www.osha.gov/SLTC/legionnairesdisease/index.html

45. OSHA. Volatile Organic Compounds in Air. OSHA Method PV2120, May 2003.

http://www.osha.gov/dts/sltc/methods/partial/pv2120/pv2120.html

46. U.S. EPA. An Introduction to Indoor Air Quality: Volatile Organic Compounds (VOCs).

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47. Yu, C. and Crump, D. (1998). A Review of Emission of VOCs from Polymeric Materials Used in 

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640-658.

I N D O O R A I R Q U A L I T Y I N C O M M E R C I A L A N D I N S T I T U T I O N A L B U I L D I N G S 2 5
U.S. Department of Labor

www.osha.gov (800) 321-OSHA (6742)

For more information: 

Occupational

Safety and Health

Administration