THE INSIDE STORY A GUIDE TO INDOOR AIR QUALITY

THE INSIDE STORY

A GUIDE TO INDOOR AIR QUALITY

Air Pollution Sources in the Home

Introduction

Indoor Air Quality in Your Home

What If You Live in an Apartment?

Improving the Air Quality in Your Home

A Look at Source-Specific Controls

Radon

Environmental Tobacco Smoke

Biological Contaminants

Stoves, Heaters, Fireplaces, and Chimneys

Household Products

Formaldehyde

Pesticides

Asbestos

Lead

Reference Guide to Major Indoor Air Pollutants in the Home

When Building a New Home

Do You Suspect Your Office Has an Indoor Air Problem?

Where to Go for Additional Information

Glossary

AIR POLLUTION SOURCES IN THE HOME

1. Moisture

2. Pressed Wood Furniture

3. Humidifier

4. Moth Repellents

5. Dry-Cleaned Goods

6. House Dust Mites

7. Personal Care Products

8. Air Freshener

9. Stored Fuels

10. Car Exhaust

11. Paint Supplies

12. Paneling

13. Wood Stove

14. Tobacco Smoke

15. Carpets

16. Pressed Wood Sub flooring

17. Drapes

18. Fireplace

19. Household Chemicals

20. Asbestos Floor Tiles

21. Pressed Wood Cabinets

22. Unvented Gas Stove

23. Asbestos Pipe Wrap

24. Radon

25. Unvented Clothes Dryer

26. Pesticides

27. Stored Hobby Products

28. Lead-Based Paint

INDOOR AIR QUALITY CONCERNS

All of us face a variety of risks to our health as we go

about our day to day lives. Driving in cars, flying in planes,

engaging in recreational activities, and being exposed to

environmental pollutants all pose varying degrees of risk.

Some risks are simply unavoidable. Some we choose to

accept because to do otherwise would restrict our ability to

lead our lives the way we want. And some are risks we might

decide to avoid if we had the opportunity to make informed

choices. Indoor air pollution is one risk that you can do

something about. In the last several years, a growing body of

scientific evidence has indicated that the air within homes and

other buildings can be more seriously polluted than the

outdoor air in even the largest and most industrialized cities.

Other research indicates that people spend approximately 90

percent of their time indoors. Thus, for many people, the risks

to health may be greater due to exposure to air pollution

indoors than outdoors. In addition, people who may be

exposed to indoor air pollutants for the longest periods of time

are often those most susceptible to the effects of indoor air

pollution. Such groups include the young, the elderly, and the

chronically ill, especially those suffering from respiratory or

cardiovascular disease.

WHY A BOOKLET ON INDOOR AIR?

While pollutant levels from individual sources may not pose

a significant health risk by themselves, most homes have

more than one source that contributes to indoor ar pollution.

There can be a serious risk from the cumulative effects of

these sources. Fortunately, there are steps that most people

can take both to reduce the risk from existing sources and to

prevent new problems from occurring. This booklet was

prepared by the U.S. Environmental Protection Agency (EPA)

and the U.S. Consumer Product Safety Commission (CPSC)

to help you decide whether to take actions that can reduce the

level of indoor air pollution in your own home.

Because so many Americans spend a lot of time in offices

with mechanical heating, cooling, and ventilation systems,

there is also a short section on the causes of poor air quality

in offices and what you can do if you suspect that your office

may have a problem. A glossary and a list of organizations

where you can get additional information are listed at the back

of this booklet.

WHAT CAUSES INDOOR AIR PROBLEMS?

Indoor pollution sources that release gases or particles

into the air are the primary cause of indoor air quality

problems in homes. Inadequate ventilation can increase

indoor pollutant levels by not bringing in enough outdoor air to

dilute emissions from indoor sources and by not carrying

indoor air pollutants out of the home. High temperature and

humidity levels can also increase concentrations of some

pollutants.

Pollutant Sources

There are many sources of indoor air pollution in any home.

These include combustion sources such as oil, gas, kerosene,

coal, wood, and tobacco products; building materials and

furnishings as diverse as deteriorated, asbestos containing

insulation, wet or damp carpet, and cabinetry or furniture

made of certain pressed wood products; products for

household cleaning and maintenance, personal care, or

hobbies; central heating and cooling systems and

humidification devices; and outdoor sources such as radon,

pesticides, and outdoor air pollution.

The relative importance of any single source depends on how

much of a given pollutant it emits and how hazardous those

emissions are. In some cases, factors such as how old the

source is and whether it is properly maintained are significant.

For example, an improperly adjusted gas stove can emit

significantly more carbon monoxide than one that is properly

adjusted. Some sources, such as building materials,

furnishings, and household products like air fresheners,

release pollutants more or less continuously. Other sources,

related to activities carried out in the home, release pollutants

intermittently. These include smoking, the use of unvented or

malfunctioning stoves, furnaces, or space heaters, the use of

solvents in cleaning and hobby activities, the use of paint

strippers in redecorating activities, and the use of cleaning

products and pesticides in housekeeping. High pollutant

concentrations can remain in the air for long periods after

some of these activities.

Amount of Ventilation

If too little outdoor air enters a home, pollutants can

accumulate o levels that can pose health and comfort

problems.

Unless they are built with special mechanical means of

ventilation, homes that are designed and constructed to

minimize the amount of outdoor air that can leak into and out

of the home may have higher pollutant levels than other

homes. However, because some weather conditions can

drastically reduce the amount of outdoor air that enters a

home, pollutants can build up even in homes that are normally

considered leaky.

HOW DOES OUTDOOR AIR ENTER A HOUSE?

Outdoor air enters and leaves a house by: infiltration,

natural ventilation, and mechanical ventilation. In a process

known as infiltration, outdoor air flows into the house through

openings, joints, and cracks in walls, floors, and ceilings, and

around windows and doors. In natural ventilation, air moves

through opened windows and doors. Air movement

associated with infiltration and natural ventilation is caused by

air temperature differences between indoors and outdoors

and by wind. Finally, there are a number of mechanical

ventilation devices, from outdoor vented fans that intermittently

remove air from a single room, such as bathrooms and

kitchen, to air handling systems that use fans and duct work to

continuously remove indoor air and distribute filtered and

conditioned outdoor air to strategic points throughout the

house. The rate at which outdoor air replaces indoor air is

described as the air exchange rate. When there is little

infiltration, natural ventilation, or mechanical ventilation, the air

exchange rate is low and pollutant levels can increase.

WHAT IF YOU LIVE IN AN APARTMENT?

Apartments can have the same indoor air problems as single

family homes because many of the pollution sources, such as

the interior building materials, furnishings, and household

products, are similar. Indoor air problems similar to those in

offices are caused by such sources as contaminated

ventilation systems, improperly placed outdoor air intakes, or

maintenance activities.

Solutions to air quality problems in apartments, as in homes

and offices, involve such actions as: eliminating or controlling

the sources of pollution, increasing ventilation, and installing

air cleaning devices. Often a resident can take the

appropriate action to improve the indoor air quality by

removing a source, altering an activity, unblocking an air

supply vent, or opening a window to temporarily increase the

ventilation; in other cases, however, only the building owner or

manager is in a position to remedy the problem. (See the

section What to Do If You Suspect a Problem on page 30.)

You can encourage building management to follow guidance

in EPA and NIOSH s Building Air Quality: A Guide for Building

Owners and Facility Managers. It is available for $24 from the

Superintendent of Documents, P.O. Box 371954, Pittsburgh,

PA 152507954; stock # 055000003904.

INDOOR AIR AND YOUR HEALTH

Health effects from indoor air pollutants may be experienced

soon after exposure or, possibly, years later.

Immediate effects may show up after a single exposure or

repeated exposures. These include irritation of the eyes,

nose, and throat, headaches, dizziness, and fatigue. Such

immediate effects are usually short term and treatable.

Sometimes the treatment is simply eliminating the person s

exposure to the source of the pollution, if it can be identified.

Symptoms of some diseases, including asthma,

hypersensitivity pneumonitis, and humidifier fever, may also

show up soon after exposure to some indoor air pollutants.

The likelihood of immediate reactions to indoor air pollutants

depends on several factors. Age and preexisting medical

conditions are two important influences. In other cases,

whether a person reacts to a pollutant depends on individual

sensitivity, which varies tremendously from person to person.

Some people canbecome sensitized to biological pollutants

after repeated exposures, and it appears that some people

can become sensitized to chemical pollutants as well.

Certain immediate effects are similar to those from colds or

other viral diseases, so it is often difficult to determine if

the symptoms are a result of exposure to indoor air pollution.

For this reason, it is important to pay attention to the time and

place the symptoms occur. If the symptoms fade or go away

when a person is away from the home and return when the

person returns, an effort should be made to identify indoor air

sources that may be possible causes. Some effects may be

made worse by an inadequate supply of outdoor air or from

the heating, cooling, or humidity conditions prevalent in the

home.

Other health effects may show up either years after exposure

has occurred or only after long or repeated periods of

exposure. These effects, which include some respiratory

diseases, heart disease, and cancer, can be severely

debilitating or fatal. It is prudent to try to improve the indoor air

quality in your home even if symptoms are not noticeable.

More information on potential health effects from particular

indoor air pollutants is provided in the section, A Look at

Source Specific Controls.

While pollutants commonly found in indoor air are responsible

for many harmful effects, there is considerable uncertainty

about what concentrations or periods of exposure are

necessary to produce specific health problems. People also

react very differently to exposure to indoor air pollutants.

Further research is needed to better understand which health

effects occur after exposure to the average pollutant

concentrations found in homes and which occur from the

higher concentrations that occur for short periods of time.

The health effects associated with some indoor air pollutants

are summarized in the chart in the middle of this booklet titled

Reference Guide to Major Indoor Air Pollutants in the Home.

IDENTIFYING AIR QUALITY PROBLEMS

Some health effects can be useful indicators of an indoor air

quality problem, especially if they appear after a person

moves to a new residence, remodels or refurnishes a home,

or treats a home with pesticides. If you think that you have

symptoms that may be related to your home environment,

discuss the with your doctor or your local health department to

see if they could be caused by indoor air pollution. You may

also want to consult a board certified allergist or an

occupational medicine specialist for answers to your

questions.

Another way to judge whether your home has or could develop

indoor air problems is to identify potential sources of indoor

air pollution. Although the presence of such sources (see

illustration at the beginning of this booklet) does not

necessarily mean that you have an indoor air quality problem,

being aware of the type and number of potential sources is an

important step toward assessing the air quality in your home.

A third way to decide whether your home may have poor

indoor air quality is to look at your lifestyle and activities.

Human activities can be significant sources of indoor air

pollution. Finally, look for signs of problems with the ventilation

in your home. Signs that can indicate your home may not have

enough ventilation include moisture condensation on windows

or walls, smelly or stuffy air, dirty central heating and air

cooling equipment, and areas where books, shoes, or other

items become moldy. To detect odors in your home, step

outside for a few minutes, and then upon reentering your

home, note whether odors are noticeable.

MEASURING POLLUTANT LEVELS

The federal government recommends that you measure the

level of radon in your home. Without measurements there is no

way to tell whether radon is present because it is a colorless,

odorless, radioactive gas. Inexpensive devices are available

for measuring radon. EPA provides guidance as to risks

associated with different levels of exposure and when the

public should consider corrective action. There are specific

mitigation techniques that have proven effective in reducing

levels of radon in the home. (See Radon section on p. 11 of

this booklet for additional information about testing and

controlling radon in homes.)

For pollutants other than radon, measurements are most

appropriate when there are either health symptoms or signs of

poor ventilation and specific sources or pollutants have been

identified as possible causes of indoor air quality problems.

Testing for many pollutants can be expensive. Before

monitoring your home for pollutants besides radon, consult

your state or local health department or professionals who

have experience in solving indoor air quality problems in

nonindustrial buildings.

WEATHERIZING YOUR HOME

The federal government recommends that homes be

weatherized in order to reduce the amount of energy needed

for heating and cooling. While weatherization is underway,

however, steps should also be taken to minimize pollution

from sources inside the home. (See Improving the Air Quality

in Your Home for recommended actions.) In addition,

residents should be alert to the emergence of signs of

inadequate ventilation, such as stuffy air, moisture

condensation on cold surfaces, or mold and mildew growth.

Additional weatherization measures should not be undertaken

until these problems have been corrected.

Weatherization generally does not cause indoor air problems

by adding new pollutants to the air. (There are a few

exceptions, such as caulking, that can sometimes emit

pollutants.) However, measures such as installing storm

windows, weather stripping, caulking, and blown in wall

insulation can reduce the amount of outdoor air infiltrating into

a home. Consequently, after weatherization, concentrations of

indoor air pollutants from sources inside the home can

increase.

THREE BASIC STRATEGIES

Source Control

Usually the most effective way to improve indoor air quality is

to eliminate individual sources of pollution or to reduce their

emissions. Some sources, like those that contain asbestos,

can be sealed or enclosed; others, like gas stoves, can be

adjusted to decrease the amount of emissions. In many

cases, source control is also a more cost efficient approach to

protecting indoor air quality than increasing ventilation

because increasing ventilation can increase energy costs.

Specific sources of indoor air pollution in your home are listed

later in this section.

Ventilation Improvements

Another approach to lowering the concentrations of indoor air

pollutants in your home is to increase the amount of outdoor

air coming indoors. Most home heating and cooling systems,

including forced air heating systems, do not mechanically

bring fresh air into the house. Opening windows and doors,

operating window or attic fans, when the weather permits, or

running a window air conditioner with the vent control open

increases the outdoor ventilation rate. Local bathroom or

kitchen fans that exhaust outdoors remove contaminants

directly from the room where the fan is located and also

increase the outdoor air ventilation rate.

It is particularly important to take as many of these steps

as possible while you are involved in short-term activities that

can generate high levels of pollutants for example, painting,

paint stripping, heating with kerosene heaters, cooking, or

engaging in maintenance and hobby activities such as

welding, soldering, or sanding. You might also choose to do

some of these activities outdoors, if you can and if weather

permits.

Advanced designs of new homes are starting to feature

mechanical systems that bring outdoor air into the home.

Some of these designs include energy efficient heat recovery

ventilators (also known as air-to-air heat exchangers). For

more information about air-to-air heat exchangers, contact the

Conservation and Renewable Energy Inquiry and Referral

Service (CAREIRS), PO Box 3048, Merrifield, VA 22116;

(800) 5232929.

Air Cleaners

There are many types and sizes of air cleaners on the market,

ranging from relatively inexpensive tabletop models to

sophisticated and expensive whole house systems. Some air

cleaners are highly effective at particle removal, while others,

including most tabletop models, are much less so. Air

cleaners are generally not designed to remove gaseous

pollutants.

The effectiveness of an air cleaner depends on how well it

collects pollutants from indoor air (expressed as a percentage

efficiency rate) and how much air it draws through the cleaning

or filtering element (expressed in cubic feet per minute). A

very efficient collector with a low air circulation rate will not be

effective, nor will a cleaner with a high air circulation rate

but a less efficient collector. The long term performance of any

air cleaner depends on maintaining it according to the

manufacturer s directions.

Another important factor in determining the effectiveness of

an air cleaner is the strength of the pollutant source. Tabletop

air cleaners, in particular, may not remove satisfactory

amounts of pollutants from strong nearby sources. People with

a sensitivity to particular sources may find that air cleaners are

helpful only in conjunction with concerted efforts to remove the

source.

Over the past few years, there has been some publicity

suggesting that house plants have been shown to reduce

levels of some chemicals in laboratory experiments. There is

currently no evidence, however, that a reasonable number of

houseplants remove significant quantities of pollutants in

homes and offices. Indoor houseplants should not be over

watered because overly damp soil may promote the growth of

microorganisms which can affect allergic individuals.

At present, EPA does not recommend using air cleaners to

reduce levels of radon and its decay products. The

effectiveness of these devices is uncertain because they only

partially remove the radon decay products and do not diminish

the amount of radon entering the home. EPA plans to do

additional research on whether air cleaners are, or could

become, a reliable means of reducing the health risk from

radon. EPA s booklet, Residential Air Cleaning Devices,

provides further information on air cleaning devices to reduce

indoor air pollutants

For most indoor air quality problems in the home, source

control is the most effective solution. This section takes a

source by source look at the most common indoor air

pollutants, their potential health effects, and ways to reduce

levels in the home. (For a summary of the points made in this

section, see the chart in the middle of this booklet titled

Reference Guide to Major Indoor Air Pollutants in the Home. )

RADON

The most common source of indoor radon is uranium in the

soil or rock on which homes are built. As uranium naturally

breaks down, it releases radon gas which is a colorless,

odorless, radioactive gas. Radon gas enters homes through

dirt floors, cracks in concrete walls and floors, floor drains, and

sumps.

When radon become strapped in buildings and

concentrations build up indoors, exposure to radon becomes

a concern.

Any home may have a radon problem. This means new and

old homes, well sealed and drafty homes, and homes with or

without basements.

Sometimes radon enters the home through well water. In a

small number of homes, the building materials can give off

radon, too. However, building materials rarely cause radon

problems by themselves.

Health Effects of Radon

The predominant health effect associated with exposure to

elevated levels of radon is lung cancer. Research suggests

that swallowing water with high radon levels may pose risks,

too, although these are believed to be much lower than those

from breathing air containing radon. Major health

organizations (like the Centers for Disease Control and

Prevention, the American Lung Association (ALA), and the

American Medical Association) agree with estimates that

radon causes thousands of preventable lung cancer deaths

each year. EPA estimates that radon causes about 14,000

deaths per year in the United States however, this number

could range from 7,000 to 30,000 deaths per year. If you

smoke and your home has high radon levels, your risk of lung

cancer is especially high.

Reducing Exposure to Radon in Homes

Measure levels of radon in your home.

You can t see radon, but it s not hard to find out if you have a

radon problem in your home. Testing is easy and should only

take a little of your time.

There are many kinds of inexpensive, do-it-yourself radon

test kits you can get through the mail and in hardware stores

and other retail outlets. Make sure you buy a test kit that has

passed EPA s testing program or is state certified. These kits

will usually display the phrase Meets EPA Requirements. If

you prefer, or if you are buying or selling a home, you can hire

a trained contractor to do the testing for you. The EPA Radon

Measurement Proficiency (RMP) Program evaluates testing

contractors. A contractor who has met EPA s requirements

will carry a special RMP identification card. EPA provides a

list of companies and individual contractors to state radon

offices.

You can call your state radon office to obtain a list of qualified

contractors in your area (call 800-SOS-RADON for a list of

state radon offices).

Refer to the EPA guidelines on how to test and interpret your

test results.

You can learn more about radon through EPA s publications,

A Citizen s Guide to Radon: The Guide to Protecting Yourself

and Your Family From Radon and Home Buyer s and Seller s

Guide to Radon, which are available from state radon offices.

Learn about radon reduction methods.

Ways to reduce radon in your home are discussed in EPA s

Consumer s Guide to Radon Reduction. You can get a copy

from your state radon office. There are simple solutions to

radon problems in homes. Thousands of homeowners have

already fixed radon problems. Lowering high radon levels

requires technical knowledge and special skills. You should

use a contractor who is trained to fix radon problems.

The EPA Radon Contractor Proficiency (RCP) Program tests

these contractors. EPA provides a list of RCP contractors to

state radon offices. A contractor who is listed by EPA will

carry a special RCP identification card. A trained RCP

contractor can study the problem in your home and help you

pick the correct treatment method. Check with your state

radon office for names of qualified or state certified radon

reduction contractors in your area.

Stop smoking and discourage smoking in your home.

Scientific evidence indicates that smoking combined with

radon is an especially serious health risk. Stop smoking and

lower your radon level to reduce lung cancer risk.

Treat radon contaminated well water.

While radon in water is not a problem in homes served by

most public water supplies, it has been found in well water. If

you've tested the air in your home and found a radon problem,

and you have a well, contact a lab certified to measure

radiation in water to have your water tested. Radon problems

in water can be readily fixed. Call your state radon office or the

EPA Drinking Water Hotline (8004264791) for more

information.

ENVIRONMENTAL TOBACCO SMOKE

Environmental tobacco smoke (ETS) is the mixture of smoke

that comes from the burning end of a cigarette, pipe, or cigar,

and smoke exhaled by the smoker. It is a complex mixture of

over 4,000 compounds, more than 40 of which are known to

cause cancer in humans or animals and many of which are

strong irritants. ETS is often referred to as secondhand

smoke and exposure to ETS is often called passive smoking.

Health Effects of Environmental Tobacco Smoke

In 1992, EPA completed a major assessment of the

respiratory health risks of ETS (Respiratory Health Effects of

Passive Smoking: Lung Cancer and Other Disorders EPA/

600/690/ 006F). The report concludes that exposure to ETS is

responsible for approximately 3,000 lung cancer deaths each

year in non-smoking adults and impairs the respiratory health

of hundreds of thousands of children.

Infants and young children whose parents smoke in their

presence are at increased risk of lower respiratory tract

infections (pneumonia and bronchitis) and are more likely to

have symptoms of respiratory irritation like cough, excess

phlegm, and wheeze. EPA estimates that passive smoking

annually causes between 150,000 and 300,000 lower

respiratory tract infections in infants and children under 18

months of age, resulting in between 7,500 and 15,000

hospitalizations each year. These children may also have a

buildup of fluid in the middle ear, which can lead to

ear infections. Older children who have been exposed to

secondhand smoke may have slightly reduced lung function.

Asthmatic children are especially at risk. EPA estimates that

exposure to secondhand smoke increases the number of

episodes and severity of symptoms in hundreds of thousands

of asthmatic children, and may cause thousands of non-

asthmatic children to develop the disease each year. EPA

estimates that between 200,000 and 1,000,000 asthmatic

children have their condition made worse by exposure to

secondhand smoke each year.

Exposure to secondhand smoke causes eye, nose, and throat

irritation. It may affect the cardiovascular system and some

studies have linked exposure to secondhand smoke with the

onset of chest pain. For publications about ETS, contact EPA

s Indoor Air Quality Information Clearinghouse (IAQ-INFO),

8004384318.

Reducing Exposure to Environmental Tobacco Smoke

Don't smoke at home or permit others to do so. Ask smokers

to smoke outdoors.

The 1986 Surgeon General s report concluded that physical

separation of smokers and nonsmokers in a common air

space, such as different rooms within the same house, may

reduce but will not eliminate nonsmokers exposure to

environmental tobacco smoke.

If smoking indoors cannot be avoided, increase ventilation in

the area where smoking takes place.

Open windows or use exhaust fans. Ventilation, a common

method of reducing exposure to indoor air pollutants, also will

reduce but not eliminate exposure to environmental tobacco

smoke.

Because smoking produces such large amounts of pollutants,

natural or mechanical ventilation techniques do not remove

them from the air in your home as quickly as they build up. In

addition, the large increases in ventilation it takes to

significantly reduce exposure to environmental tobacco

smoke can also increase energy costs substantially.

Consequently, the most effective way to reduce exposure to

environmental tobacco smoke in the home is to eliminate

smoking there.

Do not smoke if children are present, particularly infants and

toddlers.

Children are particularly susceptible to the effects of passive

smoking. Do not allow baby sitters or others who work in your

home to smoke indoors. Discourage others from smoking

around children. Find out about the smoking policies of the

day care center providers, schools, and other care givers for

your children. The policy should protect children from exposure

to ETS.

BIOLOGICAL CONTAMINANTS

Biological contaminants include bacteria, molds, mildew,

viruses, animal dander and cat saliva, house dust mites,

cockroaches, and pollen. There are many sources of these

pollutants. Pollens originate from plants; viruses are

transmitted by people and animals; bacteria are carried by

people, animals, and soil and plant debris; and household

pets are sources of saliva and animal dander. The protein in

urine from rats and mice is a potent allergen. When it dries, it

can become airborne. Contaminated central air handling

systems can become breeding grounds for mold, mildew, and

other sources of biological contaminants and can then

distribute these contaminants through the home.

By controlling the relative humidity level in a home, the

growth of some sources of biologicals can be minimized. A

relative humidity of 3050 percent is generally recommended

for homes. Standing water, water-damaged materials, or wet

surfaces also serve as a breeding ground for molds, mildews,

bacteria, and insects. House dust mites, the source of one of

the most powerful biological allergens, grow in damp, warm

environments.

Health Effects From Biological Contaminants

Some biological contaminants trigger allergic reactions,

including hypersensitivity pneumonitis, allergic rhinitis, and

some types of asthma. Infectious illnesses, such as influenza,

measles, and chicken pox are transmitted through the air.

Molds and mildews release disease causing toxins.

Symptoms of health problems caused by biological pollutants

include sneezing, watery eyes, coughing, shortness of breath,

dizziness, lethargy, fever, and digestive problems.

Allergic reactions occur only after repeated exposure to a

specific biological allergen. However, that reaction may occur

immediately upon re-exposure or after multiple exposures

over time. As a result, people who have noticed only mild

allergic reactions, or no reactions at all, may suddenly find

themselves very sensitive to particular allergens.

Some diseases, like humidifier fever, are associated with

exposure to toxins from microorganisms that can grow in large

building ventilation systems. However, these diseases can

also be traced to microorganisms that grow in home heating

and cooling systems and humidifiers. Children, elderly people,

and people with breathing problems, allergies, and lung

diseases are particularly susceptible to disease causing

biological agents in the indoor air.

Reducing Exposure to Biological Contaminants

Install and use exhaust fans that are vented to the outdoors in

kitchens and bathrooms and vent clothes dryers outdoors.

These actions can eliminate much of the moisture that builds

up from everyday activities. There are exhaust fans on the

market that produce little noise, an important consideration for

some people. Another benefit to using kitchen and bathroom

exhaust fans is that they can reduce levels of organic

pollutants that vaporize from hot water used in showers and

dishwashers.

Ventilate the attic and crawl spaces to prevent moisture

buildup. Keeping humidity levels in these areas below 50

percent can prevent water condensation on building materials.

If using cool mist or ultrasonic humidifiers, clean appliances

according to manufacturer s instructions and refill with fresh

water daily.

Because these humidifiers can become breeding grounds for

biological contaminants, they have the potential for causing

diseases such as hypersensitivity pneumonitis and humidifier

fever. Evaporation trays in air conditioners, dehumidifiers, and

refrigerators should also be cleaned frequently.

Thoroughly clean and dry water-damaged carpets and

building materials (within 24 hours if possible) or consider

removal and replacement.

Water-damaged carpets and building materials can harbor

mold and bacteria. It is very difficult to completely rid such

materials of biological contaminants.

Keep the house clean. House dust mites, pollens, animal

dander, and other allergy causing agents can be reduced,

although not eliminated, through regular cleaning.

People who are allergic to these pollutants should use

allergen proof mattress encasements, wash bedding in hot

(130 F) water, and avoid room furnishings that accumulate

dust, especially if they cannot be washed in hot water. Allergic

individuals should also leave the house while it is being

vacuumed because vacuuming can actually increase airborne

levels of mite allergens and other biological contaminants.

Using central vacuum systems that are vented to the outdoors

or vacuums with high efficiency filters may also be of help.

Take steps to minimize biological pollutants in basements.

Clean and disinfect the basement floor drain regularly. Do not

finish a basement below ground level unless all water leaks

are patched and outdoor ventilation and adequate heat to

prevent condensation are provided. Operate a dehumidifier in

the basement if needed to keep relative humidity levels

between 30 50 percent.

To learn more about biological pollutants, read Biological

Pollutants in Your Home issued by the U.S. Consumer Product

Safety Commission and the American Lung Association. For

contact information, see the section, Where to Go For

Additional Information.

STOVES, HEATERS, FIREPLACES, AND CHIMNEYS

In addition to environmental tobacco smoke, other sources of

combustion products are unvented kerosene and gas space

heaters, wood stoves, fireplaces, and gas stoves. The major

pollutants released are carbon monoxide, nitrogen dioxide,

and particles. Unvented kerosene heaters may also generate

acid aerosols.

Combustion gases and particles also come from chimneys

and flues that are improperly installed or maintained and

cracked furnace heat exchangers. Pollutants from fireplaces

and wood stoves with no dedicated outdoor air supply can be

back drafted from the chimney into the living space,

particularly in weatherized homes.

Health Effects of Combustion Products

Carbon monoxide is a colorless, odorless gas that interferes

with the delivery of oxygen throughout the body. At high

concentrations it can cause unconsciousness and death.

Lower concentrations can cause a range of symptoms from

headaches, dizziness, weakness, nausea, confusion, and

disorientation, to fatigue in healthy people and episodes of

increased chest pain in people with chronic heart disease.

The symptoms of carbon monoxide poisoning are sometimes

confused with the flu or food poisoning. Fetuses, infants,

elderly people, and people with anemia or with a history of

heart or respiratory disease can be especially sensitive to

carbon monoxide exposures.

Nitrogen dioxide is a colorless, odorless gas that irritates

the mucous membranes in the eye, nose, and throat and

causes shortness of breath after exposure to high

concentrations. There is evidence that high concentrations or

continued exposure to low levels of nitrogen dioxide increases

the risk of respiratory infection; there is also evidence from

animal studies that repeated exposures to elevated nitrogen

dioxide levels may lead, or contribute, to the development of

lung disease such as emphysema. People at particular risk

from exposure to nitrogen dioxide include children and

individuals with asthma and other respiratory diseases.

Particles, released when fuels are incompletely burned, can

lodge in the lungs and irritate or damage lung tissue. A

number of pollutants, including radon and benzo(a)pyrene,

both of which can cause cancer, attach to small particles that

are inhaled and then carried deep into the lung.

Reducing Exposure to Combustion Products in Homes

Take special precautions when operating fuel burning

unvented space heaters.

Consider potential effects of indoor air pollution if you use an

unvented kerosene or gas space heater. Follow the

manufacturers directions, especially instructions on the proper

fuel and keeping the heater properly adjusted. A persistent

yellow tipped flame is generally an indicator of maladjustment

and increased pollutant emissions. While a space heater is in

use, open a door from the room where the heater is located to

the rest of the house and open a window slightly.

Install and use exhaust fans over gas cooking stoves and

ranges and keep the burners properly adjusted.

Using a stove hood with a fan vented to the outdoors greatly

reduces exposure to pollutants during cooking. Improper

adjustment, often indicated by a persistent yellow tipped

flame, causes increased pollutant emissions. Ask your gas

company to adjust the burner so that the flame tip is blue. If

you purchase a new gas stove or range, consider buying one

with pilotless ignition because it does not have a pilot light that

burns continuously. Never use a gas stove to heat your home.

Always make certain the flue in your gas fireplace is open

when the fire place is in use.

Keep wood stove emissions to a minimum. Choose properly

sized new stoves that are certified as meeting EPA emission

standards.

Make certain that doors in old wood stoves are tight fitting.

Use aged or cured (dried) wood only and follow the

manufacturer s directions for starting, stoking, and putting out

the fire in wood stoves. Chemicals are used to pressure treat

wood; such wood should never be burned indoors. (Because

some old gaskets in wood stove doors contain asbestos,

when replacing gaskets refer to the instructions in the CPSC,

ALA, and EPA booklet, Asbestos in Your Home, to avoid

creating an asbestos problem. New gaskets are made of

fiberglass.)

Have central air handling systems, including furnaces, flues,

and chimneys, inspected annually and promptly repair cracks

or damaged parts.

Blocked, leaking, or damaged chimneys or flues release

harmful combustion gases and particles and even fatal

concentrations of carbon monoxide. Strictly follow all service

and maintenance procedures recommended by the

manufacturer, including those that tell you how frequently to

change the filter. If manufacturer s instructions are not readily

available, change filters once every month or two during

periods of use. Proper maintenance is important even for new

furnaces because they can also corrode and leak combustion

gases, including carbon monoxide. Read the

booklet What You Should Know About Combustion

Appliances and Indoor Air Pollution to learn more about

combustion pollutants.

The booklet is available by contacting CPSC, EPA s IAQ

INFO Clearinghouse, or your local ALA. (See Where to Go for

Additional Information for contact information.)

HOUSEHOLD PRODUCTS

Organic chemicals are widely used as ingredients in

household products. Paints, varnishes, and wax all contain

organic solvents, as do many cleaning, disinfecting, cosmetic,

decreasing, and hobby products. Fuels are made up of

organic chemicals. All of these products can release organic

compounds while you are using them, and, to some degree,

when they are stored.

EPA s Total Exposure Assessment Methodology (TEAM)

studies found levels of about a dozen common organic

pollutants to be 2 to 5 times higher inside homes than outside,

regardless of whether the homes were located in rural or

highly industrial areas. Additional TEAM studies indicate that

while people are using products containing organic

chemicals, they can expose themselves and others to very

high pollutant levels, and elevated concentrations can persist

in the air long after the activity is completed.

Health Effects of Household Chemicals

The ability of organic chemicals to cause health effects varies

greatly from those that are highly toxic, to those with no

known health effect. As with other pollutants, the extent and

nature of the health effect will depend on many factors

including level of exposure and length of time exposed. Eye

and respiratory tract irritation, headaches, dizziness, visual

disorders, and memory impairment are among the immediate

symptoms that some people have experienced soon after

exposure to some organics. At present, not much is known

about what health effects occur from the levels of organics

usually found in homes. Many organic compounds are known

to cause cancer in animals; some are suspected of causing,

or are known to cause, cancer in humans.

Reducing Exposure to Household Chemicals

Follow label instructions carefully.

Potentially hazardous products often have warnings aimed at

reducing exposure of the user. For example, if a label says to

use the product in a well ventilated area, go outdoors or in

areas equipped with an exhaust fan to use it. Otherwise, open

up windows to provide the maximum amount of outdoor air

possible.

Throw away partially full containers of old or unneeded

chemicals safely.

Because gases can leak even from closed containers, this

single step could help lower concentrations of organic

chemicals in your home. (Be sure that materials you decide to

keep are stored not only in a well ventilated area but are also

safely out of reach of children.) Do not simply toss these

unwanted products in the garbage can. Find out if your local

government or any organization in your community sponsors

special days for the collection of toxic household wastes. If

such days are available, use them to dispose of the unwanted

containers safely. If no such collection days are available, think

about organizing one.

Buy limited quantities.

If you use products only occasionally or seasonally, such as

paints, paint strippers, and kerosene for space heaters or

gasoline for lawn mowers, buy only as much as you will use

right away.

Keep exposure to emissions from products containing

methylene chloride to a minimum.

Consumer products that contain methylene chloride include

paint strippers, adhesive removers, and aerosol spray paints.

Methylene chloride is known to cause cancer in animals. Also,

methylene chloride is converted to carbon monoxide in the

body and can cause symptoms associated with exposure to

carbon monoxide. Carefully read the labels containing health

hazard information and cautions on the proper use of these

products. Use products that contain methylene chloride

outdoors when possible; use indoors only if the area is well

ventilated.

Keep exposure to benzene to a minimum.

Benzene is a known human carcinogen. The main indoor

sources of this chemical are environmental tobacco smoke,

stored fuels and paint supplies, and automobile emissions in

attached garages.

Actions that will reduce benzene exposure include eliminating

smoking within the home, providing for maximum ventilation

during painting, and discarding paint supplies and special

fuels that will not be used immediately.

Keep exposure to perchloroethylene emissions from newly dry

cleaned materials to a minimum.

Perchloroethylene is the chemical most widely used in dry

cleaning. In laboratory studies, it has been shown to cause

cancer in animals. Recent studies indicate that people

breathe low levels of this chemical both in homes where dry

cleaned goods are stored and as they wear dry cleaned

clothing. Dry cleaners recapture the perchloroethylene during

the dry cleaning process so they can save money by re using

it, and they remove more of the chemical during the pressing

and finishing processes. Some dry cleaners, however, do not

remove as much perchloroethylene as possible all of the time.

Taking steps to minimize your exposure to this chemical is

prudent. If dry cleaned goods have a strong chemical odor

when you pick them up, do not accept them until they have

been properly dried. If goods with a chemical odor are

returned to you on subsequent visits, try a different dry

cleaner.

FORMALDEHYDE

Formaldehyde is an important chemical used widely by

industry to manufacture building materials and numerous

household products.

It is also a byproduct of combustion and certain other natural

processes. Thus, it may be present in substantial

concentrations both indoors and outdoors.

Sources of formaldehyde in the home include building

materials, smoking, household products, and the use of

unvented, fuel burning appliances, like gas stoves or kerosene

space heaters. Formaldehyde, by itself or in combination with

other chemicals, serves a number of purposes in

manufactured products.

For example, it is used to add permanent press qualities to

clothing and draperies, as a component of glues and

adhesives, and as a preservative in some paints and coating

products.

In homes, the most significant sources of formaldehyde are

likely to be pressed wood products made using adhesives

that contain ureaformaldehyde (UF) resins. Pressed wood

products made for indoor use include: particle board (used as

sub flooring and shelving and in cabinetry and furniture);

hardwood plywood paneling (used for decorative wall

covering and used in cabinets and furniture); and medium

density fiberboard (used for drawer fronts, cabinets, and

furniture tops). Medium density fiberboard contains a higher

resin to wood ratio than any other UF pressed wood product

and is generally recognized as being the highest

formaldehyde emitting pressed wood product.

Other pressed wood products, such as softwood plywood and

flake or oriented strand board, are produced for exterior

construction use and contain the dark, or red/black colored

phenolformaldehyde (PF) resin. Although formaldehyde is

present in both types of resins, pressed woods that contain

PF resin generally emit formaldehyde at considerably lower

rates than those containing UF resin.

Since 1985, the Department of Housing and Urban

Development (HUD) has permitted only the use of plywood

and particle board that conform to specified formaldehyde

emission limits in the construction of prefabricated and mobile

homes. In the past, some of these homes had elevated levels

of formaldehyde because of the large amount of high emitting

pressed wood products used in their construction and

because of their relatively small interior space.

The rate at which products like pressed wood or textiles

release formaldehyde can change. Formaldehyde emissions

will generally decrease as products age. When the products

are new, high indoor temperatures or humidity can cause

increased release of formaldehyde from these products.

During the 1970s, many homeowners had ureaformaldehyde

foam insulation (UFFI) installed in the wall cavities of their

homes as an energy conservation measure. However, many

of these homes were found to have relatively high indoor

concentrations of formaldehyde soon after the UFFI

installation.

Few homes are now being insulated with this product. Studies

show that formaldehyde emissions from UFFI decline with

time; herefore, homes in which UFFI was installed many years

ago are unlikely to have high levels of formaldehyde now.

Health Effects of Formaldehyde

Formaldehyde, a colorless, pungent smelling gas, can cause

watery eyes, burning sensations in the eyes and throat,

nausea, and difficulty in breathing in some humans exposed at

elevated levels (above 0.1 parts per million). High

concentrations may trigger attacks in people with asthma.

There is evidence that some people can develop a sensitivity

to formaldehyde. It has also been shown to cause cancer in

animals and may cause cancer in humans.

Reducing Exposure to Formaldehyde in Homes

Ask about the formaldehyde content of pressed wood

products, including building materials, cabinetry, and furniture

before you purchase them.

If you experience adverse reactions to formaldehyde, you may

want to avoid the use of pressed wood products and other

formaldehyde emitting goods. Even if you do not experience

such reactions, you may wish to reduce your exposure as

much as possible by purchasing exterior grade products,

which emit less formaldehyde. For further information on

formaldehyde and consumer products, call the EPA Toxic

Substance Control Act (TSCA) assistance line (2025541404).

Some studies suggest that coating pressed wood products

with polyurethane may reduce formaldehyde emissions for

some period of time. To be effective, any such coating must

cover all surfaces and edges and remain intact. Increase the

ventilation and carefully follow the manufacturer s instructions

while applying these coatings. (If you are sensitive to

formaldehyde, check the label contents before purchasing

coating products to avoid buying products that contain

formaldehyde, as they will emit the chemical for a short time

after application.)

Maintain moderate temperature and humidity levels and

provide adequate ventilation.

The rate at which formaldehyde is released is accelerated by

heat and may also depend somewhat on the humidity level.

Therefore, the use of dehumidifiers and air conditioning to

control humidity and to maintain a moderate temperature can

help reduce formaldehyde emissions. (Drain and clean

dehumidifier collection trays frequently so that they do not

become a breeding ground for microorganisms.) Increasing

the rate of ventilation in your home will also help in reducing

formaldehyde levels.

PESTICIDES

According to a recent survey, 75 percent of U.S. households

used at least one pesticide product indoors during the past

year.

Products used most often are insecticides and disinfectants.

Another study suggests that 80 90 percent of most people s

exposure to pesticides occurs indoors and that measurable

levels of up to a dozen pesticides have been found in the air

inside homes. The amount of pesticides found in homes

appears to be greater than can be explained by recent

pesticide use in those households; other possible sources

include contaminated soil or dust that floats or is tracked in

from outside, stored pesticide containers, and household

surfaces that collect and then release the pesticides.

Pesticides used in and around the home include

products to control insects (insecticides), termites

(termiticides), rodents (rodenticides), fungi (fungicides), and

microbes (disinfectants). They are sold as sprays, liquids,

sticks, powders, crystals, balls, and foggers.

In 1990, the American Association of Poison Control Centers

reported that some 79,000 children were involved in common

household pesticide poisonings or exposures. In households

with children under five years old, almost one half stored at

least one pesticide product within reach of children.

EPA registers pesticides for use and requires manufacturers

to put information on the label about when and how to use the

pesticide. It is important to remember that the "cide" in

pesticides means to kill. These products can be dangerous if

not used properly.

In addition to the active ingredient, pesticides are also made

up of ingredients that are used to carry the active agent.

These carrier agents are called "inerts" in pesticides because

they are not toxic to the targeted pest; nevertheless, some

inerts are capable of causing health problems.

Health Effects From Pesticides

Both the active and inert ingredients in pesticides can be

organic compounds; therefore, both could add to the levels of

airborne organics inside homes. Both types of ingredients can

case the effects discussed in this booklet under Household

Products. However, as with other household products, there is

insufficient understanding at present about what pesticide

concentrations are necessary to produce these effects.

Exposure to high levels of cyclodiene pesticides, commonly

associated with misapplication, has produced various

symptoms, including headaches, dizziness, muscle twitching,

weakness, tingling sensations, and nausea. In addition, EPA

is concerned that cyclodienes might cause long term damage

to the liver and the central nervous system, as well as an

increased risk of cancer.

There is no further sale or commercial use permitted for the

following cyclodiene or related pesticides: chlordane, aldrin,

dieldrin, and heptachlor. The only exception is the use of

heptachlor by utility companies to control fire ants in

underground cable boxes.

Reducing Exposure to Pesticides in Homes

Read the label and follow the directions. It is illegal to use

any pesticide in any manner inconsistent with the directions on

its label.

Unless you have had special training and are certified, never

use a pesticide that is restricted to use by state certified pest

control operators. Such pesticides are simply too dangerous

for application by a non certified person. Use only the

pesticides approved for use by the general public and then

only in recommended amounts; increasing the amount does

not offer more protection against pests and can be harmful to

you and your plants and pets.

Ventilate the area well after pesticide use.

Mix or dilute pesticides outdoors or in a well ventilated area

and only in the amounts that will be immediately needed. If

possible, take plants and pets outside when applying

pesticides to them.

Use nonchemical methods of pest control when possible.

Since pesticides can be found far from the site of their original

application, it is prudent to reduce the use of chemical

pesticides outdoors as well as indoors. Depending on the site

and pest to be controlled, one or more of the following steps

can be effective: use of biological pesticides, such as Bacillus

thuringiensis, for the control of gypsy moths; selection of

disease resistant plants; and frequent washing of indoor

plants and pets. Termite damage can be reduced or

prevented by making certain that wooden building materials

do not come into direct contact with the soil and by storing

firewood away from the home.

By appropriately fertilizing, watering, and aerating lawns, the

need for chemical pesticide treatments of lawns can be

dramatically reduced.

If you decide to use a pest control company, choose one

carefully. Ask for an inspection of your home and get a written

control program for evaluation before you sign a contract. The

control program should list specific names of pests to be

controlled and chemicals to be used; it should also reflect any

of your safety concerns. Insist on a proven record of

competence and customer satisfaction.

Dispose of unwanted pesticides safely.

If you have unused or partially used pesticide containers you

want to get rid of, dispose of them according to the directions

on the label or on special household hazardous waste

collection days. If there are no such collection days in your

community, work with others to organize them.

Keep exposure to moth repellents to a minimum.

One pesticide often found in the home is

paradichlorobenzene,

a commonly used active ingredient in moth repellents. This

chemical is known to cause cancer in animals, but substantial

scientific uncertainty exists over the effects, if any, of long term

human exposure to paradichlorobenzene. EPA requires that

products containing paradichlorobenzene bear warnings such

as avoid breathing vapors to warn users of potential short

term toxic effects. Where possible, paradichlorobenzene, and

items to be protected against moths, should be placed in

trunks or other containers that can be stored in areas that are

separately ventilated from the home, such as attics and

detached garages. Paradichlorobenzene is also the key

active ingredient in many air fresheners (in fact, some labels

for moth repellents recommend that these same products be

used as air fresheners or deodorants). Proper ventilation and

basic household cleanliness will go a long way toward

preventing unpleasant odors.

Call the National Pesticide Telecommunications Network

(NPTN).

EPA sponsors the NPTN (800-858-PEST) to answer your

questions about pesticides and to provide selected EPA

publications on pesticides.

ASBESTOS

Asbestos is a mineral fiber that has been used commonly in a

variety of building construction materials for insulation and as

a fire retardant. EPA and CPSC have banned several

asbestos products. Manufacturers have also voluntarily limited

uses of asbestos. Today, asbestos is most commonly found in

older homes, in pipe and furnace insulation materials,

asbestos shingles, mill board, textured paints and other

coating materials, and floor tiles.

Elevated concentrations of airborne asbestos can occur after

asbestos containing materials are disturbed by cutting,

sanding or other remodeling activities. Improper attempts to

remove these materials can release asbestos fibers into the

air in homes, increasing asbestos levels and endangering

people living in those homes.

Health Effects of Asbestos

The most dangerous asbestos fibers are too small to be

visible.

After they are inhaled, they can remain and accumulate in the

lungs. Asbestos can cause lung cancer, mesothelioma (a

cancer of the chest and abdominal linings), and asbestosis

(irreversible lung scarring that can be fatal). Symptoms of

these diseases do not show up until many years after

exposure began. Most people with asbestos related diseases

were exposed to elevated concentrations on the job; some

developed disease from exposure to clothing and equipment

brought home from job sites.

Reducing Exposure to Asbestos in Homes

Learn how asbestos problems are created in homes. Read

the booklet, Asbestos in Your Home, issued by CPSC, the

ALA, and EPA.

To contact these organizations, see the section, Where to Go

For More Information.

If you think your home may have asbestos, don t panic!

Usually it is best to leave asbestos material that is in good

condition alone. Generally, material in good condition will not

release asbestos fiber. There is no danger unless fibers are

released and inhaled into the lungs.

Do not cut, rip, or sand asbestos containing materials.

Leave undamaged materials alone and, to the extent

possible, prevent them from being damaged, disturbed, or

touched. Periodically inspect for damage or deterioration.

Discard damaged or worn asbestos gloves, stove top pads,

or ironing board covers. Check with local health,

environmental, or other appropriate officials to find out about

proper handling and disposal procedures.

If asbestos material is more than slightly damaged, or if

you are going to make changes in your home that might

disturb it, repair or removal by a professional is needed.

Before you have your house remodeled, find out whether

asbestos materials are present.

When you need to remove or clean up asbestos, use a

professionally trained contractor.

Select a contractor only after careful discussion of the

problems in your home and the steps the contractor will take

to clean up or remove them. Consider the option of sealing off

the materials instead of removing them.

Call EPA s TSCA assistance line (2025541404) to find out

whether your state has a training and certification program for

asbestos removal contractors and for information on EPA s

asbestos programs.

LEAD

Lead has long been recognized as a harmful environmental

pollutant. In late 1991, the Secretary of the Department of

Health and Human Services called lead the number one

environmental threat to the health of children in the United

States. There are many ways in which humans are exposed to

lead:

through air, drinking water, food, contaminated soil,

deteriorating paint, and dust. Airborne lead enters the body

when an individual breathes or swallows lead particles or dust

once it has settled. Before it was known how harmful lead

could be, it was used in paint, gasoline, water pipes, and

many other products.

Old lead based paint is the most significant source of lead

exposure in the U.S. today. Harmful exposures to lead can be

created when lead based paint is improperly removed from

surfaces by dry scraping, sanding, or open flame burning.

High concentrations of airborne lead particles in homes can

also result from lead dust from outdoor sources, including

contaminated soil tracked inside, and use of lead in certain

indoor activities such as soldering and stained glass making.

Health Effects of Exposure to Lead

Lead affects practically all systems within the body. At high

levels it can cause convulsions, coma, and even death. Lower

levels of lead can adversely affect the brain, central nervous

system, blood cells, and kidneys.

The effects of lead exposure on fetuses and young children

can be severe. They include delays in physical and mental

development, lower IQ levels, shortened attention spans, and

increased behavioral problems. Fetuses, infants, and children

are more vulnerable to lead exposure than adults since lead is

more easily absorbed into growing bodies, and the tissues of

small children are more sensitive to the damaging effects of

lead. Children may have higher exposures since they are

more likely to get lead dust on their hands and then put their

fingers or other lead contaminated objects into their mouths.

Get your child tested for lead exposure. To find out where to

do this, call your doctor or local health clinic. For more

information on health effects, get a copy of the Centers for

Disease Control s, Preventing Lead Poisoning in Young

Children (October 1991).

Ways to Reduce Exposure to Lead

Keep areas where children play as dust free and clean as

possible.

Mop floors and wipe window ledges and chewable surfaces

such as cribs with a solution of powdered automatic

dishwasher detergent in warm water. (Dishwasher detergents

are recommended because of their high content of

phosphate.)

Most multipurpose cleaners will not remove lead in ordinary

dust. Wash toys and stuffed animals regularly. Make sure that

children wash their hands before meals, nap time, and

bedtime.

Reduce the risk from lead based paint.

Most homes built before 1960 contain heavily leaded paint.

Some homes built as recently as 1978 may also contain lead

paint. This paint could be on window frames, walls, the outside

of homes, or other surfaces. Do not burn painted wood since it

may contain lead.

Leave lead based paint undisturbed if it is in good condition

do not sand or burn off paint that may contain lead.

Lead paint in good condition is usually not a problem except

in places where painted surfaces rub against each other and

create dust (for example, opening a window).

Do not remove lead paint yourself.

Individuals have been poisoned by scraping or sanding lead

paint because these activities generate large amounts of lead

dust. Consult your state health or housing department for

suggestions on which private laboratories or public agencies

may be able to help test your home for lead in paint. Home

test kits cannot detect small amounts of lead under some

conditions. Hire a person with special training for correcting

lead paint problems to remove lead based paint. Occupants,

especially children and pregnant women, should leave the

building until all work is finished and cleanup is done.

For additional information dealing with lead based paint

abatement contact the Department of Housing and Urban

Development for the following two documents:

Comprehensive and Workable Plan for the Abatement of

Lead Based Paint in Privately Owned Housing:

Report to Congress (December 7, 1990) and Lead Based

Paint: Interim Guidelines for Hazard Identification and

Abatement in Public and Indian Housing (September 1990).

Do not bring lead dust into the home.

If you work in construction, demolition, painting, with

batteries, in a radiator repair shop or lead factory, or your

hobby involves lead, you may unknowingly bring lead into your

home on your hands or clothes. You may also be tracking in

lead from soil around your home. Soil very close to homes

may be contaminated from lead paint on the outside of the

building. Soil by roads and highways may be contaminated

from years of exhaust fumes from cars and trucks that used

leaded gas. Use door mats to wipe your feet before entering

the home. If you work with lead in your job or a hobby, change

your clothes before you go home and wash these clothes

separately.

Encourage your children to play in sand and grassy areas

instead of dirt which sticks to fingers and toys. Try to keep

your children from eating dirt, and make sure they wash their

hands when they come inside.

Find out about lead in drinking water.

Most well and city water does not usually contain lead. Water

usually picks up lead inside the home from household

plumbing that is made with lead materials. The only way to

know if there is lead in drinking water is to have it tested.

Contact the local health department or the water supplier to

find out how to get the water tested. Send for the EPA

pamphlet, Lead and Your Drinking Water, for more

information about what you can do if you have lead in your

drinking water. Call EPA s Safe Drinking Water Hotline

(8004264791) for more information.

Eat right.

A child who gets enough iron and calcium will absorb less lead.

Foods rich in iron include eggs, red meats, and beans. Dairy

products are high in calcium. Do not store food or liquid in

lead crystal glassware or imported or old pottery. If you reuse

old plastic bags to store or carry food, keep the printing on the

outside of the bag.

You can get a brochure, Lead Poisoning and Your Children,

and more information by calling the National Lead Information

Center, 800-LEAD-FYI.

Building a new home provides the opportunity for preventing

indoor air problems. However, it can result in exposure to

higher levels of indoor air contaminants if careful attention

is not given to potential pollution sources and the air exchange

rate.

Express your concerns about indoor air quality to your

architect or builder and enlist his or her cooperation in taking

measures to provide good indoor air quality. Talk both about

purchasing building materials and furnishings that are low

emitting and about providing an adequate amount of ventilation.

The American Society of Heating, Refrigerating, and Air

Conditioning Engineers recommends a ventilation rate of 0.35

ach (air changes per hour) for new homes, and some new

homes are built to even tighter specifications. Particular care

should be given in such homes to preventing the buildup of

indoor air pollutants to high levels.

Here are a few important actions that can make a difference:

Use radon resistant construction techniques.

Obtain a copy of the EPA booklet, Radon Resistant

Construction Techniques for Residential Construction, from

your state radon office or health agency, your state

homebuilders association, or your EPA regional office.

Choose building materials and furnishings that will keep

indoor air pollution to a minimum.

There are many actions a homeowner can take to select

products that will prevent indoor air problems from occurring a

couple of them are mentioned here. First, use exterior grade

pressed wood products made with phenolformaldehyde resin

in floors, cabinetry, and wall surfaces. Or, as an alternative,

consider using solid wood products. Secondly, if you plan to

install wall to wall carpet on concrete in contact with the

ground, especially concrete in basements, make sure that an

effective moisture barrier is installed prior to installing the

carpet. Do not permanently adhere carpet to concrete with

adhesives so that the carpet can be removed if it becomes wet.

Provide proper drainage and seal foundations in new

construction.

Air that enters the home through the foundation can contain

more moisture than is generated from all occupant activities.

Become familiar with mechanical ventilation systems and

consider installing one.

Advanced designs of new homes are starting to feature

mechanical systems that bring outdoor air into the home.

Some of these designs include energy efficient heat recovery

ventilators (also known as air to air heat exchangers).

Ensure that combustion appliances, including furnaces,

fireplaces, wood stoves, and heaters, are properly vented and

receive enough supply air.

Combustion gases, including carbon monoxide, and particles

can be back drafted from the chimney or flue into the living

space if the combustion appliance is not properly vented or

does not receive enough supply air. Back drafting can be a

particular problem in weatherized or tightly constructed homes.

Installing a dedicated outdoor air supply for the combustion

appliance can help prevent back drafting.

Indoor air quality problems are not limited to homes. In fact,

many office buildings have significant air pollution sources.

Some of these buildings may be inadequately ventilated. For

example, mechanical ventilation systems may not be

designed or operated to provide adequate amounts of

outdoor air. Finally, people generally have less control over the

indoor environment in their offices than they do in their homes.

As a result, there has been an increase in the incidence of

reported health problems.

HEALTH EFFECTS

A number of well identified illnesses, such as Legionnaire s

disease, asthma, hypersensitivity pneumonitis, and humidifier

fever, have been directly traced to specific building problems.

These are called building related illnesses. Most of these

diseases can be treated nevertheless, some pose serious

risks.

Sometimes, however, building occupants experience

symptoms that do not fit the pattern of any particular illness

and are difficult to trace to any specific source. This

phenomenon has been labeled sick building syndrome.

People may complain of one or more of the following

symptoms: dry or burning mucous membranes in the nose,

eyes, and throat; sneezing; stuffy or runny nose; fatigue or

lethargy; headache; dizziness; nausea; irritability an

forgetfulness. Poor lighting, noise, vibration, thermal

discomfort, and psychological stress

may also cause, or contribute to, these symptoms.

There is no single manner in which these health problems appear.

In some cases, problems begin as workers enter their offices

and diminish as workers leave; other times, symptoms

continue until the illness is treated. Sometimes there are

outbreaks of illness among many workers in a single building;

in other cases, health symptoms show up only in individual workers.

In the opinion of some World Health Organization experts, up

to 30 percent of new or remodeled commercial buildings may

have unusually high rates of health and comfort complaints

from occupants that may potentially be related to indoor air

quality.

WHAT CAUSES PROBLEMS?

Three major reasons for poor indoor air quality in office

buildings are the presence of indoor air pollution sources;

poorly designed, maintained, or operated ventilation systems;

and uses of the building that were unanticipated or poorly

planned for when the building was designed or renovated.

Sources of Office Air Pollution

As with homes, the most important factor influencing indoor air

quality is the presence of pollutant sources. Commonly found

office pollutants and their sources include environmental

tobacco smoke; asbestos from insulating and fire retardant

building supplies; formaldehyde from pressed wood products;

other organics from building materials, carpet, and other office

furnishings, cleaning materials and activities, rest room air

fresheners, paints, adhesives, copying machines, and

photography and print shops; biological contaminants from

dirty ventilation systems or water damaged walls, ceilings, and

carpets; and pesticides from pest management practices.

Ventilation Systems

Mechanical ventilation systems in large buildings are

designed and operated not only to heat and cool the air, but

also to draw in and circulate outdoor air. If they are poorly

designed, operated, or maintained, however, ventilation

systems can contribute to indoor air problems in several ways.

For example, problems arise when, in an effort to save

energy, ventilation systems are not used to bring in adequate

amounts of outdoor air. Inadequate ventilation also occurs if

the air supply and return vents within each room are blocked

or placed in such a way that outdoor air does not actually

reach the breathing zone of building occupants. Improperly

located outdoor air intake vents can also bring in air

contaminated with automobile and truck exhaust, boiler

emissions, fumes from dumpsters, or air vented from rest

rooms. Finally, ventilation systems can be a source of indoor

pollution themselves by spreading biological contaminants

that have multiplied in cooling towers, humidifiers,

dehumidifiers, air conditioners, or the inside surfaces of

ventilation duct work.

Use of the Building

Indoor air pollutants can be circulated from portions of the

building used for specialized purposes, such as restaurants,

print shops, and dry cleaning stores, into offices in the same

building. Carbon monoxide and other components of

automobile exhaust can be drawn from underground parking

garages through stairwells and elevator shafts into office

spaces.

In addition, buildings originally designed for one purpose

may end up being converted to use as office space. If not

properly modified during building renovations, the room

partitions and ventilation system can contribute to indoor air

quality problems by restricting air recirculation or by providing

an inadequate supply of outdoor air.

WHAT TO DO IF YOU SUSPECT A PROBLEM

If you or others at your office are experiencing health or

comfort problems that you suspect may be caused by indoor

air pollution, you can do the following:

Talk with other workers, your supervisor, and union

representatives to see if the problems are being experienced

by others and urge that a record of reported health complaints

be kept by management, if one has not already been

established.

Talk with your own physician and report your problems to the

company physician, nurse, or health and safety officer.

Call your state or local health department or air pollution

control agency to talk over the symptoms and possible causes.

Encourage building management to obtain a copy of Building

Air Quality: A Guide for Building Owners and Facility Managers.

Building Air Quality (BAQ) is simply written, yet provides

comprehensive information for identifying, correcting, and

preventing indoor air quality problems. BAQ also provides

supporting information such as when and how to select

outside technical assistance, how to communicate with others

regarding indoor air issues, and where to find additional

sources of information. BAQ is available for $24 from U.S.

GPO, Superintendent of Documents, P.O. Box 371954,

Pittsburgh, PA 152507954; stock #055000003904.

Frequently, indoor air quality problems in large commercial

buildings cannot be effectively identified or remedied without

a comprehensive building investigation. These investigations

may start with written questionnaires and telephone

consultations in which building investigators assess the history

of occupant symptoms and building operation procedures. In

some cases, these inquiries may quickly uncover the problem

and on site visits are unnecessary.

More often, however, investigators will need to come to the

building to conduct personal interviews with occupants, to look

for possible sources of the problems, and to inspect the

design and operation of the ventilation system and other

building features. Because taking measurements of pollutants

at the very low levels often found in office buildings is

expensive and may not yield information readily useful in

identifying problem sources, investigators may not take many

measurements. The process of solving indoor air quality

problems that result in health and comfort complaints can be a

slow one, involving several trial solutions before successful

remedial actions are identified.

If a professional company is hired to conduct a building

investigation, select a company on the basis of its experience

in identifying and solving indoor air quality problems in

nonindustrial buildings.

Work with others to establish a smoking policy that eliminates

involuntary nonsmoker exposure to environmental tobacco

smoke.

Call the National Institute for Occupational Safety and Health

(NIOSH) for information on obtaining a health hazard

evaluation of your office (800-35-N-EACH), or contact the

Occupational Safety and Health Administration, (202)

2198151.

Federal Information Services

Federal agencies with indoor air quality information may be

contacted as follows:

U.S. Environmental Protection Agency (EPA)

Public Information Center

401 M St., SW

Washington, DC 20460

(202) 260-7751

Indoor Air Quality Information Clearinghouse (IAQ INFO)

P.O. Box 37133

Washington, DC 200137133

(800) 438-4318

(301) 585-9020

Operates Monday to Friday from 9 to 5 Eastern Standard

Time (EST). Distributes EPA publications, answers questions

on the phone, and makes referrals to other nonprofit and

governmental organizations.

National Radon Hotline

(800) SOS-RADON

Information recording operates 24 hours a day.

National Lead Information Center

(800) LEAD-FYI

Operates 24 hours a day, seven days a week. Callers may

order an information package. To speak to an information

specialist, call (800)4245323. Operates Monday to Friday

from 8:30 to 5 EST.

National Pesticides Telecommunications Network

National toll free number: (800) 858-PEST

In Texas: (806) 7433091

Operates Monday to Friday from 8 to 6 Central Standard Time.

Provides information about pesticides to the general public

and the medical, veterinary, and professional communities.

RCRA/Super fund Hotline

National toll free number: (800) 4249346

In Washington, DC area: (703) 4129810

Operates Monday to Friday from 8:30 to 7:30 EST. Provides

information on regulations under both the Resources

Conservation and Recovery Act (including solid and

hazardous waste issues) and the Superfund law.

Safe Drinking Water Hotline

(800) 4264791

Operates Monday to Friday from 8:30 to 5 EST. Provides

information on regulations under the Safe Drinking Water Act,

lead and radon in drinking water, filter information, and a

list of state drinking water offices.

TSCA Assistance Information Service

(202) 5541404

Operates Monday to Friday from 8:30 to 5 EST. Provides

information on regulations under the Toxic Substances Control

Act and on EPA's asbestos program.

U.S. Consumer Product Safety Commission (CPSC)

Washington, DC 202070001

Product Safety Hotline: (800) 638-CPSC

Teletypewriter for the hearing impaired (outside Maryland):

(800) 638-8270; Maryland only: (800) 492-8104. Recorded

information is available 24 hours a day when calling from a

touch tone phone.

Operators are on duty Monday to Friday from 10:30 to 4 EST

to take complaints about unsafe consumer products.

U.S. Department of Housing and Urban Development

Office of Energy and the Environment

Washington, DC 20410

HUD USER National toll free number: (800) 245-2691

In Washington, DC area: (301) 251-5154.

U.S. Department of Energy

Office of Conservation and Renewable Energy

1000 Independence Ave., SW

Washington, DC 20585

Conservation and Renewable Energy Inquiry and Referral

Service (CAREIRS)

PO Box 3048, Merrifield, VA 22116; (800) 523-2929.

Operates Monday to Friday from 9 to 5 EST. Provides

consumer information on conservation and renewable energy

in residences.

U.S. Public Health Service

Division of Federal Occupational Health

Office of Environmental Hygiene, Region III, Room 1310

3535 Market St., Philadelphia, PA 19104

(215) 596-1888; fax: 215-596-5024

Provides indoor air quality consultative services to federal

agency managers.

Centers for Disease Control and Prevention

Lead Poisoning Prevention Branch

4770 Buford Highway, NE (F42), Atlanta, GA 30341-3724

(800) 488-7330

Office on Smoking and Health

Centers for Disease Control and Prevention

U.S. Department of Health and Human Services

4770 Buford Highway, NE (K50), Atlanta, GA 30341-3724

(404) 488-5701

Occupational Safety and Health Administration

Office of Information and Consumer Affairs

Room N-3647

200 Constitution Avenue, NW, Washington, DC 20210

(202) 219-8151

Bonneville Power Administration

Portland, OR 97208

General Services Administration

18th and F Streets, NW, Washington, DC 20405

Tennesee Valley Authority

Industrial Hygiene Branch

Multipurpose Building (1B), Muscle Shoals, AL 35660

State and Local Organizations

Your questions or concerns about indoor air problems can

frequently be answered by the government agencies in your

state or local government. Responsibilities or indoor air

quality issues are usually divided among many different

agencies.

Calling or writing the agencies responsible for health or air

quality control is the best way to start getting information from

your state or local government. To obtain state agency

contacts, write or call EPA s IAQ Information Clearinghouse,

(800) 4384318.

CPSC REGIONAL OFFICES

Eastern Regional Center

6 World Trade Center

Vesey Street, 3rd Floor Room 350

New York, NY 10048-0950

(212) 466-1612

Central Regional Center

230 South Dearborn Street Room 2944

Chicago, IL 60604-1601

(312) 353-8260

Western Regional Center

600 Harrison Street Room 245

San Francisco, CA 94107

(415) 744-2966

States in Region

Connecticut, District of Columbia, Delaware, Florida,

Massachusetts, Maryland, Maine, North Carolina, New

Hampshire, New York, Pennsylvania, South Carolina, Rhode

Island, Virginia, Vermont, West Virginia

Alabama, Georgia, Iowa, Illinois, Indiana, Kansas, Kentucky,

Michigan, Minnesota, Missouri, Mississippi, North Dakota,

Nebraska, Ohio, South Dakota, Tennessee, Wisconsin

Alaska, Arkansas, Arizona, California, Colorado, Hawaii,

Idaho, Louisiana, Montana, New Mexico, Nevada, Oklahoma,

Oregon, Texas, Utah, Washington, Wyoming

EPA REGIONAL OFFICES

Address inquiries to the Indoor Air Coordinators in the EPA

regional offices at the following addresses:

Region 1

EPA

John F. Kennedy Federal Building

Boston, MA 02203

617-565-4502

Region 2

EPA (2AWM-RAD)

26 Federal Plaza

New York, NY 10278

212-264-4418

Region 3

EPA

841 Chestnut Building

Philadelphia, PA 19107

215-595-8322

215-597-4084 (radon)

Region 4

EPA

345 Courtland Street NE

Atlanta, GA 30365

404-347-2864

Region 5

EPA AT-18L

77 W. Jackson Blvd.

Chicago, IL 60604

312-353-2205

Region 6

EPA

First Interstate Bank Tower

1445 Ross Avenue

Dallas, TX 75202

214-655-7223

Region 7

EPA ARTX / ARBR-RAID

726 Minnesota Avenue

Kansas City, KS 66101

913-551-7222

Region 8

EPA 999 18th Street, Suite 500

Denver, CO 80202-2466

303-293-1709

The following organizations have information discussed in this

booklet. EPA s IAQ Information Clearinghouse, (800)438-

4318, can provide the names of a variety of organizations that

have information on all of the issues discussed in this

publication.

American Association of Poison Control Centers

3800 Reservoir Rd., NW

Washington, DC 20007

American Society of Heating, Refrigerating, and Air-

Conditioning

(ASHRAE)

1791 Tullie Circle NE

Atlanta, GA 30329

World Health Organization

Publications Center

49 Sheridan Avenue

Albany, NY 12210

Your local American Lung Association (ALA)

1740 Broadway

New York, NY 10019

(800) LUNG-USA

GLOSSARY

Acid aerosol

Acidic liquid or solid particles that are small enough to

become airborne. High concentrations of acid aerosols can

be irritating to the lungs and have been associated with some

respiratory diseases, such as asthma.

Animal dander

Tiny scales of animal skin.

Allergen

A substance capable of causing an allergic reaction because

of an individual s sensitivity to that substance.

Allergic rhinitis

Inflammation of the mucous membranes in the nose that is

caused by an allergic reaction.

Building-related illness

A discrete, identifiable disease or illness that can be traced to

a specific pollutant or source within a building. (Contrast with

Sick building syndrome ).

Chemical sensitization

Evidence suggests that some people may develop health

problems characterized by effects such as dizziness, eye and

throat irritation, chest tightness, and nasal congestion that

appear whenever they are exposed to certain chemicals.

People may react to even trace amounts of chemicals to

which they have become sensitized.

Environmental tobacco smoke

Mixture of smoke from the burning end of a cigarette, pipe, or

cigar and smoke exhaled by the smoker (also secondhand

smoke or passive smoking).

Fungi

Any of a group of parasitic lower plants that lack chlorophyll,

including molds and mildews.

Humidifier fever

A respiratory illness caused by exposure to toxins from

microorganisms found in wet or moist areas in humidifiers

and air conditioners. Also called air conditioner or ventilation

fever.

Hypersensitivity pneumonitis

A group of respiratory diseases that cause inflammation of the

lung (specifically granulomatous cells). Most forms of

hypersensitivity pneumon-itis are caused by the inhalation of

organic dusts, including molds.

Organic compounds

Chemicals that contain carbon. Volatile organic compounds

vaporize at room temperature and pressure. They are found in

many indoor sources, including many common household

products and building materials.

Picocurie

A unit for measuring radioactivity, often expressed as

picocuries per liter of air.

Pressed wood products

A group of materials used in building and furniture

construction that are made from wood veneers, particles, or

fibers bonded together with an adhesive under heat and

pressure.

Radon and radon decay products

Radon is a radioactive gas formed in the decay of uranium.

The radon decay products (also called radon daughters or

progeny) can be breathed into the lung where they continue to

release radiation as they further decay.

Sick building syndrome

Term that refers to a set of symptoms that affect some number

of building occupants during the time they spend in the

building and diminish or go away during periods when they

leave the building.

Cannot be traced to specific pollutants or sources within the

building. (Contrast with Building related illness ).

Ventilation rate

The rate at which indoor air enters and leaves a building.

Expressed in one of two ways: the number of changes of

outdoor air per unit of time (air changes per hour, or ach ) or

the rate at which a volume of outdoor air enters per unit of

time (cubic feet per minute, or cfm )