The Inside Story: A Guide to Indoor Air Quality (2023)

The information provided in this safety guide is based on current scientific and technical knowledge of the topics presented and reflects the jurisdictional limits established by the statutes of the co-authoring agencies. Following the advice given does not necessarily provide complete protection in all situations or from all health risks that indoor air pollution can cause.

Introduction

Indoor Air Quality Concerns

We are all exposed to a variety of health risks in our daily lives. Driving cars, flying planes, participating in recreational activities, and being exposed to environmental contaminants all pose different levels of risk, some of which simply cannot be avoided. Some we accept because otherwise we would limit our ability to live our lives the way we want. And some risks that we could avoid if we had the opportunity to make informed decisions. Indoor air pollution is a risk you can do something about.

In recent years, mounting scientific evidence indicates that the air inside homes and other buildings, even in the largest and most industrialized cities, may be more polluted than the air outside. Another survey shows that people spend around 90% of their time indoors. Therefore, for many people, the health risks from exposure to air pollution indoors may be greater than outdoors.

Additionally, people who may have been exposed to indoor air pollutants for the longest time are often the most vulnerable to the effects of indoor air pollution. These groups include the young, the elderly, and the chronically ill, especially those with respiratory or cardiovascular disease.

Why an indoor air safety guide?

Although concentrations of pollutants from individual sources may not pose a significant health risk on their own, most homes have more than one source contributing to indoor air pollution. The cumulative effect of these sources can pose a serious risk. Fortunately, there are steps most people can take to reduce risk from existing sources and prevent new problems from arising. This safety guide is issued by the US Environmental Protection Agency (EPA) and the US Consumer Product Safety Commission (CPSC) to help you decide if you should take steps that can reduce air pollution. indoor air in your own home.

Because many Americans spend a lot of time in offices with mechanical heating, cooling, and ventilation systems, there is also a short section on what causes poor office air quality and what you can do if you suspect your office has a problem. . A glossary and a list of organizations from which you can obtain additional information are available in this document.

Indoor air quality in your home

What causes indoor air problems?

Indoor air pollution sources that release gases or particles into the air are the leading cause of indoor air quality problems in homes. Inadequate ventilation can increase indoor pollution levels by not bringing in enough outdoor air to dilute emissions from indoor sources and by not transporting indoor air pollutants out of the home. High temperature and humidity levels can also increase the levels of some pollutants.

pollution sources

There are many sources of indoor air pollution in every home. This includes combustion sources such as oil, gas, kerosene, coal, wood, and tobacco products; Building materials and furniture as diverse as damaged insulation containing asbestos, wet or damp carpeting and cabinets, or furniture made from certain compressed wood products; household cleaning and care products, personal care or hobbies; central heating and cooling systems and humidifiers; and external sources such as radon, pesticides, and outdoor air pollution.

The relative importance of an individual source depends on how much of a given pollutant it emits and how dangerous those emissions are. In some cases, factors such as the age of the well and its correct maintenance are important. For example, an improperly adjusted gas stove can emit much more carbon monoxide than a properly adjusted one.

Some sources, such as building materials, home furnishings, and household products such as air fresheners, release pollutants on a more or less continuous basis. Other sources related to household activities sometimes release pollutants. This includes smoking, the use of stoves, stoves or heaters that are working or not working properly, the use of solvents in cleaning activities and hobbies, the use of strippers in home renovations, and the use of household cleaners and pesticides. After some of these activities, high concentrations of pollutants can remain in the air for a long time.

amount of ventilation

When insufficient outdoor air is brought into a home, pollutants can build up to levels that can lead to health and comfort issues. Unless built with specialized mechanical means of ventilation, homes designed and built to minimize the amount of outside air that can "leak" in and out of the home may have higher levels of pollution than other homes. However, because some weather conditions can drastically reduce the amount of outdoor air drawn into a home, pollutants can accumulate even in homes that are generally considered "leaky."

How does outside air enter a house?

Outdoor air enters and leaves a home through: infiltration, natural ventilation, and mechanical ventilation. In a process known as infiltration, outside air flows into the home through openings, cracks, and crevices in walls, floors, and ceilings, as well as around windows and doors. With natural ventilation, air flows through open doors and windows. Air movement associated with infiltration and natural ventilation is caused by differences in air temperature between indoors and outdoors and by wind. Finally, there is a range of mechanical ventilation devices, from outdoor fans that intermittently extract air from a single room, such as a bathroom and kitchen, to ventilation systems that use fans and ducts to continuously extract indoor air and distribute filtered air and conditioning. diffuse. Outside air to strategic points of the house. The rate at which outdoor air replaces indoor air is called the air exchange rate. With low infiltration, natural ventilation, or mechanical ventilation, the air exchange rate is low and contamination levels may increase.

And if you live in an apartment?

Apartments can have the same indoor air problems as single-family homes because many of the sources of pollutants, such as building materials, furniture, and household products, are similar. Indoor air problems similar to those in offices are caused by sources such as dirty ventilation systems, poorly located external air intakes, or maintenance work.

Solutions to air quality problems in homes, homes, and offices include measures such as: removing or controlling sources of pollution, improving ventilation, and installing air purification devices. Often, a resident can take appropriate steps to improve indoor air quality by removing a source, changing an activity, uncovering a vent, or opening a window to temporarily increase ventilation; however, in other cases, only the building owner or manager can resolve the issue. (See What to do if you suspect a problem.) You can encourage building management to follow EPA and NIOSH's Air Quality in Buildings: A Guide for Building Owners and Facility Managers. To receive the loose-leaf version of Indoor Air Quality with appendices, an index, and a full set of helpful forms, as well as the recently released Indoor Air Quality Action Plan, request GPO Stock Number 055-000- 00602-4, for $28, contact Contact: Superintendent of Documents, U.S. Government Press Office (GPO), P.O. Box 371954, Pittsburgh, PA 15250-7954, or by phone (202) 512-1800, fax (202) 512-2250.

Improving the air quality in your home

indoor air and your health

Health effects from indoor air pollutants can occur soon after exposure or possibly years later.

Immediate effects may occur after single or repeated exposure. These include eye, nose and throat irritation, headaches, dizziness and tiredness. These immediate effects are usually short-term and treatable. Sometimes treatment is simply to eliminate the person's exposure to the source of contamination, if it can be identified. Symptoms of some diseases, such as asthma, hypersensitivity pneumonitis, and humidifier fever, can also appear shortly after exposure to some indoor air pollutants.

The likelihood of immediate reactions to indoor air pollutants depends on several factors. Age and previous illnesses are two important influences. In other cases, a person's reaction to a pollutant depends on individual sensitivity, which varies greatly from person to person. Some people may become sensitized after repeated exposure to biological contaminants, and it appears that some people may also become sensitized to chemical contaminants.

Certain immediate effects are similar to those of the common cold or other viral illnesses, so it is often difficult to determine if symptoms are due to exposure to indoor air pollution. For this reason, it is important to pay attention to when and where the symptoms appear. If symptoms lessen or disappear when a person is away from home and return when the person returns, an attempt should be made to identify indoor air sources that could be possible causes. Some effects may be exacerbated by an insufficient supply of outdoor air or by the prevailing heating, cooling, or humid conditions in the home.

Other health effects may occur years after exposure or only after prolonged or repeated exposure. These effects, which include some respiratory and heart diseases and cancer, can be very debilitating or deadly. It is advisable to try to improve the quality of the indoor air in your home, even if there are no symptoms. For more information on the potential health effects of certain indoor air pollutants, see the A Look at Source-Specific Controls section.

Although pollutants commonly found in indoor air are responsible for many adverse effects, there is considerable uncertainty about what concentrations or durations of exposure are required to produce specific health problems. People also react very differently to exposure to indoor air pollutants. More research is needed to better understand the health effects of exposure to average household levels of pollutants and those of short-term exposure to higher levels.

The health effects associated with some indoor air pollutants are summarized in the "Reference Guide to Major Household Indoor Air Pollutants" section.

Identification of air quality problems

Some health effects can be useful indicators of an indoor air quality problem, especially when they occur after a person has moved into a new apartment, remodeled or redecorated a home, or treated a home with pesticides. If you think you have symptoms that could be related to your home environment, discuss them with your doctor or local health department to see if they may be caused by indoor air pollution. You may also want to see a licensed allergist or occupational medicine doctor to get answers to your questions.

Another way to assess whether your home has or could have indoor air problems is to identify potential sources of indoor air pollution. While the presence of such sources does not necessarily mean that you have an indoor air quality problem, knowing the types and number of potential sources is an important step in evaluating the air quality in your home.

A third way to decide if your home has 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 ventilation problems in your home. Signs that your home may not be adequately ventilated include condensation on windows or walls, smelly or stale air, dirty central heating and air conditioning equipment, and areas where books, shoes, or other items are moldy. To detect odors in your home, go outside for a few minutes and, when you re-enter the house, see if you notice any odors.

Measurement of contaminant levels

The federal government recommends measuring the level of radon in your home. Without measurements, it is not possible to determine if radon is present, since it is a colourless, odorless and radioactive gas. Inexpensive devices are available to measure radon. EPA provides guidance on the risks associated with different levels of exposure and when the public should consider taking corrective action. There are specific abatement techniques that have been shown to be effective in reducing radon concentrations in homes. (See Radon for more information on home radon testing and control.)

For contaminants other than radon, measurements are most appropriate when health symptoms or signs of poor ventilation are present and specific sources or contaminants have been identified as potential causes of indoor air quality problems. Testing for many contaminants can be expensive. Before monitoring your home for contaminants other than radon, check with your local or state health department or with professionals experienced in troubleshooting indoor air quality in non-industrial buildings.

spice of your house

The federal government recommends aging homes to reduce energy requirements for heating and cooling. However, as weathering continues, steps must also be taken to minimize contamination from indoor sources. (See “Improving the air quality in your home” for recommended actions.) In addition, residents should be on the lookout for signs of inadequate ventilation, such as: B. stale air, moisture condensation on cold surfaces, or mold growth. No further weathering measurements should be made until these issues are resolved.

Weathering does not usually cause indoor air problems as it adds new pollutants to the air. (There are some exceptions, such as caulking, which can sometimes release contaminants.) However, measures like installing shutters, caulking, caulking, and blown-in wall insulation can reduce the amount of outside air drawn into a home. Consequently, after wear and tear, concentrations of indoor air pollutants can increase from indoor sources.

Three Basic Strategies

control source

Generally, the most effective way to improve indoor air quality is to eliminate individual sources of pollutants or reduce their emissions. Some sources, such as those containing asbestos, can be sealed or enclosed; others, like gas stoves, can be modified to reduce the amount of emissions. In many cases, source control is also a more cost-effective approach to protecting indoor air quality than increased ventilation, since increased 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 reducing the concentration of indoor air pollutants in your home is to increase the amount of outdoor air drawn into indoor spaces. Most home heating and cooling systems, including forced-air heating systems, do not mechanically introduce fresh air into the home. Opening windows and doors, running window or attic fans when weather permits, or running a window air conditioner with the vent control open increases the rate of outdoor ventilation. Local bathroom or kitchen fans with external exhaust remove pollutants directly from the room where the fan is located and also increase the rate of ventilation of outdoor air.

It is especially important to perform as many of these steps as possible while doing short-term activities that may generate high levels of pollutants, such as: B. Painting, stripping, heating with oil stoves, cooking or maintenance work, and hobbies such as welding , weld or grind. You can also do some of these activities outdoors if you can and the weather permits.

New advanced home designs are beginning to feature mechanical systems that bring outside air into the home. Some of these designs include energy efficient heat recovery fans (also known as air-to-air heat exchangers). For more information on air-to-air heat exchangers, contact the Conservation and Renewable Energy Inquiry and Referral Service (CAREIRS), PO Box 3048, Merrifield, VA 22116; (800) 523-2929.

air filter

There are many types and sizes of air purifiers on the market, from relatively inexpensive tabletop models to more sophisticated and expensive complete home systems. Some air purifiers are very effective at removing particles, while others, including most tabletop models, are much less so. Air purifiers are generally not designed to remove gaseous pollutants.

The effectiveness of an air filter depends on how well it removes contaminants from indoor air (expressed as an efficiency percentage) and how much air it pulls through the cleaning element or filter (expressed in cubic feet per minute). A highly efficient collector with low airflow will not be effective, nor will a purifier with high airflow, but a less efficient collector will. The long-term performance of an air purifier depends on maintaining it according to the manufacturer's instructions.

Another important factor in determining the effectiveness of an air purifier is the strength of the polluting source. In particular, tabletop air fresheners may not remove satisfactory levels of contaminants from strong nearby sources. People with sensitivity to specific sources may find air fresheners only helpful in conjunction with a concerted effort to eliminate the source.

In recent years, there have been some publications suggesting that houseplants have been shown in laboratory experiments to reduce levels of some chemicals. However, there is currently no evidence that a reasonable number of houseplants remove significant amounts of pollutants in homes and offices. Indoor plants should not be over-watered, as soil that is too wet can encourage the growth of microorganisms that can affect allergy sufferers.

The EPA does not currently recommend the use of air purifiers to reduce levels of radon and its breakdown products. The effectiveness of these devices is uncertain because they only partially remove radon breakdown products and do not reduce the amount of radon entering the home. The EPA plans to further investigate whether air purifiers are, or could become, a reliable means of reducing radon health risks. EPA Brochure,Air purification devices for private homes., provides more information on air purification devices to reduce indoor air pollutants.

For most indoor air quality problems in the home, source control is the most effective solution. This section looks source by source at the most common indoor air pollutants, their potential health impacts, and ways to reduce exposure to pollution in the home. (For a summary of the points raised in this section, see the section titled "Reference Guide to Major Household Indoor Air Pollutants.") The EPA recently published,Ozone generators sold as air purifiers🇧🇷 The purpose of this document (available only through this website) is to provide accurate information on the use of ozone generating devices in occupied indoor spaces. This information is based on the most credible scientific evidence currently available.

The EPA recently published,"Should you clean the air ducts in your house?"EPA-402-K-97-002, October 1997. This document is intended to help consumers answer this often confusing question. The document explains what an air duct cleaning is, provides guidance to help consumers decide if their home should be serviced, and provides helpful information on choosing an air duct cleaner, determining if the duct cleaning was done correctly and prevent air pollution. channels

A look at font-specific controls

RADON (Rn)

The most common source of indoor radon is uranium in the soil or the rock on which houses are built. When uranium naturally decays, it releases radon gas, which is a colorless and odorless radioactive gas. Radon gas enters homes through dirt floors, cracks in concrete walls and floors, drains, and wetlands. When radon is trapped in buildings and indoor concentrations increase, radon exposure becomes a problem.

Any home can have a radon problem. This means new and old houses, well-sealed and draft-free houses, and houses with or without a basement.

Sometimes radon enters the house through well water. In some homes, building materials can also emit radon. However, building materials alone rarely cause radon problems.

health effects of radon

The predominant health effect associated with exposure to high levels of radon is lung cancer. Research suggests that swallowing water with high levels of radon may also pose risks, although these are considered to be much lower than those from radon-containing breathing air. Major health organizations (such as the Centers for Disease Control and Prevention, the American Lung Association (ALA), and the American Medical Association) concur in estimating that radon causes thousands of preventable deaths from lung cancer each year. The EPA estimates that radon causes about 14,000 deaths a year in the United States, but that number can range from 7,000 to 30,000 deaths a year. If you smoke and your home has high levels of radon, your risk of lung cancer is particularly high.

Reduce Radon Exposure in Homes

Measure radon levels in your home.

You can't see radon, but it's not hard to tell if you have a radon problem in your home. The test is easy and should take very little time.

There are many types of low-cost do-it-yourself radon test kits available through the mail, at hardware stores, and other outlets. Be sure to purchase a test kit that has passed the EPA testing program or is state certified. These kits 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. Testing (gauge) contractors have been evaluated by EPA's voluntary National Radon Proficiency Program (RPP). One EPA-compliant contractor used an EPA-issued RPP identification card. EPA has provided a list of companies and individual contractors on this website, which has also been made available to state radon agencies. you should call yourState Radon Agencyfor a list of qualified contractors in your area. You can also contact the National Environmental Health Association (NEHA) -http://www.neha.orgor o National Radon Safety Board (NRSB) -http://www.nrsb.orgfor a list of competent radon measurement and/or mitigation providers.

Consult the EPA guidelines for information on how to perform tests and interpret test results.

You can get more information about radon in EPA publications,A Citizen's Guide to Radon: The Guide to Protecting You and Your Family from RadonmiRadon Buyers and Sellers Guide, which are also available to youState Radon Agency.

Learn more about radon abatement methods.

Ways to reduce radon in your home are discussed at the EPAConsumer's Guide to Reducing Radon🇧🇷 You can get a copy of yourState Radon Agency🇧🇷 There are simple solutions to radon problems in the home. Thousands of homeowners have already solved their radon problems. Reducing high levels of radon requires technical knowledge and special skills. You should hire a contractor who is trained to fix radon problems.

A trained radon abatement specialist can assess the problem in your home and help you choose the right treatment. check with yourState Radon Agencyby the name of qualified or certified radon abatement companies in your area.

Quit smoking and avoid smoking in your home.

Scientific evidence indicates that smoking in combination with radon poses a particularly serious health risk. Quit smoking and lower your radon levels to reduce your risk of lung cancer.

Treat radon-contaminated water well.

Although radon is not a problem in domestic water supplied by most public water systems, it has been found in well water. If you tested the air in your home and found a radon problem and you have a well, contact a certified water radiation laboratory to have your water tested. Radon water problems are easy to fix. call yoursState Radon Agencyor the EPA Drinking Water Hotline (800-426-4791) for more information.

ENVIRONMENTAL TOBACCO SMOKE (ETS)

Environmental tobacco smoke (ETS) is the mixture of smoke from the burning end of a cigarette, pipe, or cigar and the smoke exhaled by the smoker. It is a complex mixture of more than 4,000 compounds, more than 40 of which are known to cause cancer in humans or animals, and many of which are potent irritants. ETS is often called "secondhand smoke" and exposure to ETS is often called "secondhand smoke."

Health Effects of Secondhand Smoke

In 1992, the EPA completed a comprehensive evaluation of the effects of smoking on respiratory health (Respiratory Health Effects of Passive Smoking: Lung Cancer and Other Disorders EPA/600/6-90/006F). The report concludes that ETS exposure is responsible for approximately 3,000 lung cancer deaths in nonsmoking adults each year and adversely affects the respiratory health of hundreds of thousands of children.

Babies and young children whose parents smoke around them are at increased risk of lower respiratory tract infections (pneumonia and bronchitis) and are more likely to experience symptoms of respiratory irritation such as coughing, excessive phlegm, and wheezing. The EPA estimates that secondhand smoke causes between 150,000 and 300,000 lower respiratory tract infections in infants and children under 18 months of age annually, resulting in between 7,500 and 15,000 hospitalizations per year. These children may also have fluid buildup in the middle ear, which can lead to ear infections. Older children who have been exposed to secondhand smoke may have slightly impaired lung function.

Asthmatic children are particularly at risk. The EPA estimates that secondhand smoke exposure increases the number of episodes and severity of symptoms in hundreds of thousands of children with asthma and may cause thousands of non-asthmatic children to develop the disease each year. The EPA estimates that between 200,000 and 1,000,000 children with asthma worsen their condition from secondhand smoke each year. Secondhand smoke causes irritation to the eyes, nose, and throat. It can affect the cardiovascular system, and some studies have linked secondhand smoke exposure to chest pain. For ETS publications, seeIndoor Air Quality Publicationsor contact EPA's Indoor Air Quality Information Center (IAQ INFO), 800-438-4318 or (703) 356-4020.

Reduce exposure to secondhand smoke

Don't smoke in your home and don't let other people smoke. Ask smokers to smoke outdoors.

The 1986 Surgeon General's report concluded that physically separating smokers and nonsmokers in a shared airspace, such as different rooms in the same house, can reduce, but not eliminate, nonsmokers' exposure to secondhand smoke.

If indoor smoking cannot be avoided, increase ventilation in the smoking area.

Open windows or use exhaust fans. Ventilation, a common method of reducing exposure to indoor air pollutants, will also reduce, but not eliminate, exposure to secondhand smoke. Because smoking creates large amounts of contaminants, natural or mechanical ventilation techniques will not remove them from the air in your home as quickly as they accumulate. In addition, the large increases in ventilation required to significantly reduce environmental exposure to tobacco smoke can also significantly increase energy costs. Consequently, the most effective way to reduce exposure to tobacco smoke in the home is to quit smoking in the home.

Do not smoke in the presence of children, especially babies and young children.

Children are particularly vulnerable to the effects of secondhand smoke. Do not allow babysitters or other people who work in your home to smoke in the house. Discourage others from smoking around children. Find out about the anti-smoking regulations of nurseries, schools and other caregivers of your children. The directive should protect children from exposure to ETS.

BIOLOGICAL CONTAMINANTS

Biological contaminants include bacteria, mold, fungus, viruses, pet dander and cat saliva, dust mites, cockroaches, and pollen. There are many sources of these contaminants. Pollen comes from plants; Viruses are transmitted by humans and animals; The bacteria are transmitted by humans, animals, soil, and plant residues; and pets are sources of animal dander and saliva. Protein in rat and mouse urine is a powerful allergen. When it is dry, it can remain in the air. Contaminated central ventilation systems can become breeding grounds for mold and other sources of biological contaminants, and then spread these contaminants throughout the home.

Controlling the relative humidity in a home can minimize the growth of some biological sources. In general, a relative humidity of 30 to 50 percent is recommended for living spaces. Standing water, water-damaged materials, or wet surfaces also serve as breeding grounds for fungi, bacteria, and insects. Dust mites, the source of one of the most powerful biological allergens, thrive in warm, humid environments.

Health Effects of Biological Contaminants

Some biological contaminants trigger allergic reactions, such as hypersensitivity pneumonitis, allergic rhinitis, and some types of asthma. Infectious diseases like the flu, measles, and chickenpox are spread through the air. Mold releases toxins that cause disease. Symptoms of health problems caused by biological contaminants 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, this reaction can occur immediately after a new exposure or after multiple exposures over time. As a result, people who have experienced only mild or no allergic reactions can suddenly become very sensitive to certain allergens.

Some illnesses, such as humidifier fever, are associated with exposure to toxins from microorganisms that can grow in the ventilation systems of large buildings. However, these diseases can also be traced to microorganisms that grow in home heating and cooling systems and humidifiers. Children, the elderly, and people with respiratory difficulties, allergies, and lung diseases are particularly susceptible to airborne biological pathogens.

Reduced exposure to biological contaminants

Install and use outdoor exhaust fans in kitchens and bathrooms, and vent outdoor clothes dryers.

These measures can remove much of the moisture accumulated from daily activities. There are cooker hoods on the market that produce low noise, which is an important consideration for some people. Another benefit of using kitchen and bathroom range hoods is that they can reduce the levels of organic contaminants that evaporate from hot water used in showers and dishwashers.

Ventilate the attic and basement to prevent moisture buildup.

Keeping humidity below 50% in these areas can prevent water condensation on building materials.

If you use ultrasonic or cool mist humidifiers, clean the units according to the manufacturer's instructions and fill them with fresh water every day.

Because these humidifiers can become breeding grounds for biological contaminants, they can cause illnesses such as hypersensitivity pneumonia and humidifier fever. The evaporative trays of air conditioners, dehumidifiers, and refrigerators should also be cleaned periodically.

Thoroughly clean and dry (within 24 hours if possible) or remove and replace water-damaged carpeting and building materials.

Water-damaged carpeting and building materials can harbor fungus and bacteria. It is very difficult to completely remove these biological contaminant materials.

Keep the house clean. Dust mites, pollen, pet dander, and other allergy triggers can be reduced by regular cleaning, but not eliminated.

People allergic to these contaminants should use allergen-proof mattress covers, wash bedding in hot water (130 degrees Fahrenheit), and avoid dusty furniture, especially if it cannot be washed in hot water. People with allergies should also leave the house while vacuuming, as vacuuming can increase levels of allergens from dust mites and other airborne biological contaminants. Using central vacuums that vent to the outside or vacuums with heavy-duty filters can also help.

Take steps to minimize biological contaminants in basements.

Clean and sanitize your basement drain regularly. Do not finish a basement unless all water leaks are fixed and there is adequate outside ventilation and heating to prevent condensation. If necessary, use a dehumidifier in the basement to keep the relative humidity between 30 and 50 percent.

For more information on biological contaminants, readBiological contaminants in your homeIssued by the US Consumer Product Safety Commission and American Lung Association. See the Additional Information section for contact information.

STOVES, HEATERS, FIREPLACES AND FIREPLACES

In addition to secondhand tobacco smoke, other sources of combustion products include ventless kerosene and gas heaters, wood stoves, fireplaces, and gas furnaces. The main pollutants emitted are carbon monoxide, nitrogen dioxide and particulate matter. Unvented kerosene heaters can also produce acid aerosols.

Flue gases and particulates also come from improperly installed or maintained chimneys and flues and from cracked furnace heat exchangers. In particularly weather-beaten homes, pollutants from fireplaces and wood-burning stoves can "back up" from the fireplace into the living room without their own outside air supply.

Health Effects of Combustion Products

carbon monoxide(CO) is a colorless, odorless gas that disrupts the flow of oxygen throughout the body. In high concentrations it can cause unconsciousness and death. Lower levels can produce a variety of symptoms, from headache, dizziness, weakness, nausea, confusion, and disorientation to fatigue in healthy people and episodes of increasing chest pain in people with chronic heart disease. The symptoms of carbon monoxide poisoning are sometimes confused with those of the flu or food poisoning. Unborn babies, infants, the elderly, and people with anemia or a history of heart or respiratory disease may be particularly sensitive to carbon monoxide exposure.

nitrogen dioxide(NO2) is a colorless, odorless gas that irritates the mucous membranes of the eyes, nose, and throat and causes difficulty breathing when exposed to high concentrations. There is evidence that high levels or prolonged exposure to low levels of nitrogen dioxide increase the risk of respiratory infection; There is also evidence from animal studies that repeated exposure to high levels of nitrogen dioxide can cause or contribute to the development of lung diseases such as emphysema. People at particular risk from nitrogen dioxide are children and people with asthma and other respiratory conditions.

Particlereleased when fuels are not completely burned can lodge in the lungs and irritate or damage lung tissue. Several pollutants, including radon and benzo(a)pyrene, which can cause cancer, bind to small particles that are inhaled and then carried deep into the lungs.

Reduce exposure to combustion products in homes.

Take special precautions when operating fuel-burning ventless space heaters.

Consider the possible effects of indoor air pollution when using a ventless kerosene or gas heater. Follow the manufacturer's instructions, especially those regarding the correct fuel and proper heater setting. A sustained yellow tipped flame is usually an indicator of a mismatch and increased emissions. While a heater is running, open a door from the room where the heater is located to the rest of the house and slightly open a window.

Install and use exhaust fans over gas stoves and ranges and keep burners properly adjusted.

Using an exhaust fan with an external fan will significantly reduce exposure to contaminants during cooking. An incorrect fit, often indicated by a continuous yellow flame at the tip, will cause increased polluting emissions. Ask your gas supplier to adjust the burner so that the tip of the flame turns blue. If you're buying a new stove or gas stove, consider buying one with pilotless ignition, since it doesn't have a continuously burning pilot flame. Never use a gas stove to heat your home. Always make sure the gas fireplace vent is open when the fireplace is in use.

Minimize emissions from wood stoves. Choose new, correctly sized stoves that meet EPA emissions standards.

Make sure the doors on old wood stoves close tightly. Use only aged or hardened (dry) wood and follow manufacturer's instructions for lighting, fueling, and extinguishing fires in wood-burning stoves. Chemicals are used to treat wood under pressure; This wood should never be burned indoors. (Since some old wood stove door gaskets contain asbestos, follow the CPSC, ALA, and EPA brochure instructions when replacing gaskets,asbestos in your hometo avoid an asbestos problem. The new seals are fiberglass.)

Have central ventilation systems, including fireboxes, flues, and chimneys, inspected annually and promptly repaired for cracks or damaged parts.

Clogged, leaking or damaged chimneys or chimneys release harmful combustion gases and particulates and even deadly levels of carbon monoxide. Strictly follow all manufacturer's recommended service and maintenance procedures, including how often to change the filter. If the manufacturer's instructions are not available, change the filters once or twice a month during the period of use. Proper maintenance is also important for new stoves, as they too can corrode and leak flue gases, including carbon monoxide.

HOME'S PRODUCTS

Organic chemicals are commonly used as ingredients in household products. Paints, varnishes, and waxes contain organic solvents, as do many cleaning, disinfecting, cosmetic, degreasing, and hobby products. Fuels consist of organic chemicals. All of these products can release organic compounds during use and, to some extent, during storage.

EPA's Total Exposure Assessment Methodology (TEAM) studies have found that levels of about a dozen common organic contaminants are 2 to 5 times higher inside homes than outdoors, regardless of whether the homes are found in rural or highly industrialized areas. Additional TEAM studies indicate that people can expose themselves and others to very high levels of contaminants when using products containing organic chemicals, and that high levels can remain in the air long after the activity is complete.

Health Effects of Household Chemicals

The ability of organic chemicals to cause health effects varies widely, from highly toxic to those with no known health effects. As with other contaminants, the magnitude and nature of the health effects depend on many factors, including the level of exposure and the duration of exposure. Eye and respiratory irritation, headaches, dizziness, blurred vision, and memory problems are among the immediate symptoms that some people experience shortly after exposure to some organic compounds. Currently, not much is known about the health effects of common levels of organic matter in the home. Many organic compounds are known to cause cancer in animals; Some are suspected or known to cause cancer in humans.

Reduce exposure to household chemicals

Follow label directions carefully.

Potentially hazardous products often have warning labels designed to reduce user exposure. For example, if a label says to use the product in a well-ventilated area, go outside or into an area equipped with an exhaust fan to use it. If not, open windows to provide as much outside air as possible.

Safely dispose of partially filled containers of old or obsolete chemicals.

Since vapors can escape even from closed containers, this one step can help reduce levels of organic chemicals in your home. (Make sure any materials you choose to store are kept not only in a well-ventilated area, but also out of the reach of children.) Don't throw those unwanted items in the trash. Find out if your local government or an organization in your community sponsors special days for the collection of household hazardous waste. If these days are available, use them to safely dispose of unwanted containers. If such a collection day is not available, consider arranging one.

Buy limited quantities.

If you only use products occasionally or seasonally, e.g. B. Paint, stripper, and space heating kerosene or lawn mower gasoline, only buy what you will use immediately.

Minimize exposure to emissions from products containing methylene chloride.

Consumer products containingmethylene hydrochlorideThese include strippers, adhesive removers, and spray paints. Methylene chloride is known to cause cancer in animals. Additionally, methylene chloride converts to carbon monoxide in the body and can cause symptoms associated with carbon monoxide exposure. Read labels carefully for information on health risks and precautions for proper use of these products. If possible, use products containing methylene chloride outdoors; use indoors only if 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 secondhand smoke, stored fuel and paint supplies, and automobile exhaust from attached garages. Measures to reduce exposure to benzene include not smoking in the home, providing maximum ventilation while painting, and disposing of paint supplies and specialty fuels that are not used immediately.

Minimize exposure to perchlorethylene emissions from freshly dry-cleaned materials.

Perchlorethylene is the most widely used chemical in dry cleaning. It has been shown to cause cancer in animals in laboratory studies. Recent studies show that people breathe small amounts of this chemical both in homes where dry cleaning products are stored and when wearing dry cleaning clothing. Dry cleaners recapture perchlorethylene during the dry cleaning process so they can save money by reusing it, and they remove more of the chemical during the pressing and refining process. However, some chemical cleaners do not always remove as much PERC as possible. It is advisable to take steps to minimize your exposure to this chemical. If dry-cleaned items have a strong chemical odor when you pick them up, do not accept them until they have dried properly. If you receive products with a chemical smell on subsequent visits, try another dry cleaner.

FORMAT SKIN

FormaldehydeIt is an important chemical widely used by industry to make building materials and many household products. It is also a byproduct of combustion and other natural processes. Therefore, it can be present in significant concentrations both indoors and outdoors.

Household sources of formaldehyde include building materials, smoking, household products, and the use of unvented fuel-burning appliances, such as gas stoves or kerosene heaters. Formaldehyde, alone or in combination with other chemicals, serves many purposes in manufactured products. For example, it is used to impart permanent printing properties to clothing and draperies, as a component of adhesives and adhesives, and as a preservative in some paints and coatings.

In homes, the most significant sources of formaldehyde are likely to be chipboard products made with adhesives containing urea formaldehyde (UF) resins. Compressed wood products manufactured for interior use include: particleboard (used in subfloors and shelving, as well as cabinets and furniture); hardwood plywood panels (for use as decorative wall coverings and for use in cabinets and furniture); and medium-density cardboard (used for drawer fronts, cupboards, and furniture tops). Medium-density fiberboard contains a higher ratio of resin to wood than any other UF particleboard product and is generally recognized as the highest formaldehyde emitting particleboard product.

Other particleboard products, such as softwood plywood and oriented strandboard or flakeboard, are manufactured for use in outdoor construction and contain dark or red/black colored phenol formaldehyde (PF) resin. Although formaldehyde is present in both types of resin, particle boards containing PF resin generally emit formaldehyde at significantly lower levels than those containing UF resin.

Since 1985, the Department of Housing and Urban Development (HUD) has only allowed the use of plywood and particleboard that meets certain formaldehyde emission limits in the construction of mobile and manufactured homes. Historically, some of these houses had elevated levels of formaldehyde due to the large number of high-emissivity compressed wood products used in their construction and their relatively small interior space.

The rate at which products such as compressed wood or textiles release formaldehyde can change. Formaldehyde emissions generally decrease as products age. With new products, high internal temperatures or humidity may cause an increase in the release of formaldehyde from these products.

In the 1970s, many homeowners installed urea formaldehyde foam insulation (UFFI) in the voids of their homes as an energy-saving measure. However, relatively high levels of formaldehyde were observed inside many of these houses shortly after the installation of the UFFI. Few houses are now insulated with this product. Studies show that formaldehyde emissions from UFFI decrease over time; As such, homes that had UFFI installed many years ago are unlikely to have high levels of formaldehyde.

Health Effects of Formaldehyde

Formaldehyde, a colorless gas with a pungent odor, can cause watery eyes, burning eyes and throat, nausea, and shortness of breath in some people exposed to high levels (greater than 0.1 parts per million). Elevated levels can trigger attacks in people with asthma. There is evidence that some people may develop sensitivity to formaldehyde. It has also been shown to cause cancer in animals and can cause cancer in humans.

Reduce exposure to formaldehyde in homes

Before you buy, ask about the formaldehyde content of particleboard products, including building materials, cabinets, and furniture.

If you have adverse reactions to formaldehyde, avoid using chipboard products and other products that emit formaldehyde. Even if you don't have these reactions, you may want to reduce your exposure as much as possible by purchasing outdoor products that emit less formaldehyde. For more information on formaldehyde and consumer products, contact the EPA's Toxic Substances Control Act (TSCA) Hotline (202-554-1404).

Some studies suggest that coating hardboard products with polyurethane can reduce formaldehyde emissions over a period of time. To be effective, this coating must cover all surfaces and edges and remain intact. Increase ventilation and carefully follow manufacturer's instructions when applying these coatings. (If you are sensitive to formaldehyde, check the label before purchasing coating products to avoid purchasing products that contain formaldehyde, which emit the chemical for a short time after application.) Maintain moderate temperature and humidity and ensure adequate ventilation. The rate at which formaldehyde is released is accelerated by heat and can also depend somewhat on humidity. Therefore, the use of dehumidifiers and air conditioners to control humidity and maintain a moderate temperature can help reduce formaldehyde emissions. (Drain and clean dehumidifier drain pans frequently to prevent them from becoming a breeding ground for microorganisms.) Increasing the ventilation rate in your home also helps reduce formaldehyde levels.

PESTICIDES

According to a recent survey, 75% of American households use at least onepesticidesProduct indoors last year. Insecticides and disinfectants are the most used. Another study suggests that 80% of most people are exposed to pesticides indoors, and measurable levels of up to a dozen pesticides have been found in indoor air. The amount of pesticides found in homes appears to be greater than can be explained by recent pesticide use in these homes; Other possible sources include contaminated soil or dust that is blown in or brought in from outside, stored pesticide containers, and household surfaces that collect and then release pesticides. Pesticides used in and around the home include products to control insects (insecticides), termites (termiticides), rodents (rodicides), fungi (fungicides), and microbes (disinfectants). They are sold as sprays, liquids, sticks, powders, crystals, mints, and vaporizers.

In 1990, the American Association of Poison Control Centers reported that approximately 79,000 children were involved in poisoning or exposure to household pesticides. In households with children under the age of five, nearly half have at least one pesticide product stored within children's reach.

The EPA registers the use of pesticides and requires manufacturers to include information on the label about when and how the pesticide should be used. It's important to remember that the "-cide" in pesticides means "to kill."These products can be dangerous if not used correctly.

In addition to the active ingredient, pesticides also consist of ingredients that serve as vehicles for the active ingredient. These carriers are called "inert" in pesticides because they are not toxic to the target pest; However, some inert substances can cause health problems.

Effects of pesticides on health

Both the active and inert ingredients of pesticides can be organic compounds; Therefore, both could increase the levels of organic matter in the air in homes. Both types of ingredients can produce the effects discussed under Household Products in this document, but as with other household products, there is currently not enough knowledge about what concentrations of pesticides are required to produce these effects.

Exposure to high levels of cyclodiene pesticides, commonly associated with misapplication, has produced a variety of symptoms including headaches, dizziness, muscle spasms, weakness, tingling, and nausea. Additionally, the EPA is concerned that cyclodienes may cause long-term damage to the liver and central nervous system and increase the risk of cancer.

The following cyclodienes or related pesticides are not permitted for resale or commercial use: chlordane, aldrin, dieldrin, and heptachlor. The one exception is the use of heptachlor by utility companies to control fire ants in underground wiring boxes.

Reduce exposure to pesticides in homes

Read the label and follow the instructions. It is illegal to use a pesticide in any way that does not follow the directions on the label.

Never use a pesticide restricted for use by government certified pest controllers unless you have been specially trained and certified. These pesticides are simply too dangerous to be applied by an uncertified person. Use only pesticides approved for use by the general public and only in recommended amounts; Increasing the amount does not provide better pest protection and may be harmful to you, your plants, and pets.

Ventilate the area well after using pesticides.

Mix or dilute pesticides outdoors or in a well-ventilated area and only in amounts needed right away. If possible, take plants and pets outside if you use pesticides on them.

Use non-chemical pest control methods whenever possible.

Since pesticides can be found far from where they were originally applied, it is prudent to reduce the use of chemical pesticides both outdoors and indoors. Depending on the location and the pest to be controlled, one or more of the following measures may be effective: use of biological pesticides such as Bacillus thuringiensis to control the gypsy moth; selection of disease resistant plants; and frequent washing of houseplants and pets. Termite damage can be reduced or avoided by ensuring that wood building materials do not come in direct contact with the ground and by storing firewood outside the home. Proper fertilizing, watering, and aerating your lawn can dramatically reduce the need for chemical pesticide treatments.

When choosing a pest control company, choose one carefully.

Request a home inspection and receive a written inspection schedule for your evaluation before signing a contract. The control program should list the specific names of the pests to be controlled and the chemicals to be used; it should also reflect any of your security concerns. Insist on proven experience and customer satisfaction.

Dispose of unwanted pesticides safely.

If you have unused or partially used pesticide containers that you want to throw away, dispose of them according to label directions or on special Household Hazardous Waste collection days. If your community does not have such collection days, work with others to organize them.

Keep exposure to moth repellants to a minimum.

A common household pesticide is paradichlorobenzene, an active ingredient commonly used in moth repellents. This chemical is known to cause cancer in animals, but there is great scientific uncertainty about the effects, if any, of long-term human exposure to paradichlorobenzene. The EPA requires that products containing paradichlorobenzene carry warnings such as "avoid breathing vapors" to alert users of potential short-term toxic effects. Whenever possible, paradichlorobenzene and items to be protected from moths should be stored in suitcases or other containers that can be stored in separate, ventilated areas of the home, such as attics and detached garages. Paradichlorobenzene is also the main active ingredient in many air fresheners (in fact, some moth repellent labels recommend that the same products be used as air fresheners or deodorants). Proper ventilation and basic home cleaning go a long way in preventing unpleasant odors.

Call the National Pesticide Telecommunications Network (NPTN).

EPA sponsors the NPTN (800-858-PEST) to answer your pesticide questions and provide you with selected EPA pesticide publications.

ASBESTOS

AsbestosIt is a mineral fiber commonly used in a variety of building materials for insulation and as a flame retardant. The EPA and CPSC have banned several asbestos products. Manufacturers have also voluntarily restricted the use of asbestos. Today, asbestos is most commonly found in older homes, pipe and furnace insulation materials, asbestos shingles, cardboard, textured paint, and other siding and shingle materials.

Elevated levels of asbestos in the air can occur after asbestos-containing materials have been disturbed by cutting, grinding, or other disturbances. Improper attempts to remove these materials can release asbestos fibers into the air inside homes, increasing asbestos levels and putting the people living in those homes at risk.

Effects of asbestos on health

The most dangerous asbestos fibers are too small to be visible. Once inhaled, they can remain and accumulate in the lungs. Asbestos can cause lung cancer, mesothelioma (a cancer of the lining of the chest and abdomen), and asbestosis (irreversible scarring of the lungs that can be fatal). Symptoms of these diseases do not appear until many years after exposure begins. Most people with asbestos-related illnesses have been exposed to high levels at work; some became ill from exposure to clothing and equipment brought home from the workplace.

Reduce exposure to asbestos in homes

Find out how asbestos problems arise in homes.

read the little book,asbestos in your home, published by the CPSC, ALA and EPA. See the More Information section for information on how to contact these organizations.

If you think your house may have asbestos, don't panic!

Asbestos material is generally best left in good condition alone. In general, materials in good condition do not emit asbestos fibers. There is no danger unless the fibers are released and inhaled into the lungs.

Do not cut, shred or shred materials containing asbestos.

Leave untouched materials alone and protect them from damage, interference, or contact as much as possible. Inspect regularly for damage or wear. Discard any asbestos gloves, stove mats, or ironing board covers that are damaged or worn. Consult local health, environmental or other relevant authorities for information on proper handling and disposal.

When asbestos material is more than slightly damaged, or if you are making changes to your home that may disturb you, it should be repaired or removed by a professional. Before you remodel your home, find out if there are any asbestos materials.

If you need to remove or remediate asbestos, contact a professionally trained contractor.

Select a contractor only after carefully discussing the problems in your home and the steps the contractor will take to fix or correct them. Consider sealing the materials instead of removing them.

Call the EPA's TSCA Hotline (202-554-1404) to find out if 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 summoned the leader"The number one environmental threat to the health of children in the United States."People are exposed to lead in many ways: through the air, drinking water, food, contaminated soil, paint decay, and dust. Airborne lead enters the body when a person inhales or swallows lead particles or dust once they have settled. Before it was known how harmful lead could be, it was used in paint, gasoline, water pipes, and many other products.

Old lead paint is the largest source of lead in the United States today. Harmful exposure to lead can occur when lead-based paint is improperly removed from surfaces by dry scraping, grinding, or burning with an open flame. High concentrations of lead particles in the air of homes can also be caused by lead dust from outside sources, including contaminated soil brought in and the use of lead in certain indoor activities, such as soldering and stained glass.

Health Effects of Lead Exposure

Lead affects virtually every system in the body. At high levels, it can cause seizures, coma, and even death. Lower lead levels can affect the brain, central nervous system, blood cells, and kidneys.

The effects of lead exposure on fetuses and young children can be serious. These include delays in physical and mental development, lower IQ scores, shorter attention spans, and increased behavioral problems. Fetuses, infants, and children are more susceptible to lead exposure than adults because lead is more easily absorbed by the growing body and young children's tissues are more sensitive to the harmful effects of lead. Children may have higher exposures because they are more likely to get lead dust on their hands and then put their fingers or other lead-contaminated objects in their mouths.

Have your child tested for lead exposure. To find out where you can get it, call your doctor or your local health clinic. For more information on health effects, see the Centers for Disease Control issue, Preventing Lead Poisoning in Young Children (October 1991).

Ways to Reduce Lead Exposure

Keep areas where children play as dust-free and clean as possible.

Scrub floors and clean window sills and chewy surfaces, such as cribs, with a solution of detergent in warm water. (Dishwasher detergents are recommended due to their high phosphate content.) Most general purpose cleaners will not remove lead from common dust. Wash toys and stuffed animals regularly. Make sure children wash their hands before meals, naps, and at bedtime.

Reduce the risk of lead paint.

Most homes built before 1960 contain high-lead paint. Some homes built in 1978 may also contain lead-based paint. This color can be on window frames, walls, on the outside of houses or on any other surface. Do not burn painted wood as it may contain lead.

Leave lead-based paint intact if it is in good condition; do not sand or burn paint that may contain lead.

Lead paint in good condition is generally not a problem, except where painted surfaces rub against each other and create dust (for example, when opening a window).

Do not remove lead paint yourself.

People have been poisoned by scraping or grinding lead paint, since these activities generate large amounts of lead dust. Contact your state department of health or housing for suggestions on which private labs or public agencies can help you test your home for lead paint. Home test kits do not detect low levels of lead under certain conditions. Have someone with special training in lead paint troubleshooting remove the lead paint. Residents, particularly children and pregnant women, must leave the building until all work and cleanup is complete.
For more information on lead paint abatement, contact the Department of Housing and Urban Development to request the following two documents: Comprehensive and Feasible Plan for the Reduction of Lead Paint in Private Homes: Report to Congress (December 7 1990) and Lead-Based Paint: Interim Guidelines for Identifying and Reducing Hazards in Public and Indian Housing (Sept. 1990).

Do not bring lead dust home.

If you work in construction, demolition, painting, batteries, radiator shop, lead factory, or your hobby involves lead, you could unknowingly bring lead into your home on your hands or clothing. You can also track lead in the soil around your home. Soil near homes may be contaminated by lead paint on the exterior of the building. The soil on roads and highways can be contaminated by years of exhaust fumes from cars and trucks that used leaded gasoline. Use mats to dry your feet before entering the house. If you use lead in your work or hobby, change your clothes before you go home and wash them separately. Encourage your children to play on sand and grass surfaces instead of dirt that sticks to fingers and toys. Try to discourage your children from eating dirt and make sure they wash their hands when they come into the house.

Learn about lead in drinking water.

Most city and well water does not normally contain lead. Water normally accumulates lead inside household pipes made of lead materials. The only way to determine if there is lead in your drinking water is to test it. Contact your local health department or water company to find out how to test your water. Request the EPA brochure Lead and Your Drinking Water for more information on what to do if your drinking water contains lead. Call EPA's Safe Drinking Water Hotline (800-426-4791) for more information.

Eat properly.

A child who gets enough iron and calcium absorbs less lead. Iron-rich foods include eggs, red meat, and beans. Dairy products are rich in calcium. Do not store food or liquids in imported or antique ceramic or lead crystal glass. If you are reusing old plastic bags to store or transport groceries, leave the print 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.

WHAT ABOUT THE CARPET?

In recent years, many consumers have associated a variety of symptoms with installing new carpet. Scientists have not been able to determine if the chemicals emitted by new carpets are to blame. When installing new carpet, you should follow these steps:

• Talk to your carpet dealer. Ask about carpet emissions.
• Ask the dealer to unroll and air out the carpet in a well-ventilated area before installation.
• Ask for low emission adhesives when you need adhesives.
• Consider leaving the site during and immediately after carpet installation. You can schedule the installation when most family members or office workers are away.
• Make sure the retailer requires the installer to follow the Carpet and Rug Institute installation guidelines.
• Open doors and windows. Increasing the amount of fresh air in the home reduces exposure to most chemicals released from carpets. During and after installation, use window fans, air conditioners, or other mechanical ventilation devices you have installed in your home to vent smoke to the outside. Let them run for 48 to 72 hours after installing the new carpet.
• Contact your carpet dealer if unpleasant odors persist.
• Follow the manufacturer's instructions for proper carpet care.

WHEN BUILDING A NEW HOUSE

Building a new home offers the opportunity to prevent indoor air problems. However, it can lead to exposure to higher concentrations of indoor air pollutants if attention is not paid to potential sources of pollution and the rate of air renewal.

Express your indoor air quality concerns to your architect or contractor and ask for their cooperation in taking steps to ensure good indoor air quality. Discuss the purchase of low-emission building materials and furniture, as well as proper ventilation.

The American Society of Heating, Refrigerating, and Air-Conditioning Engineers (ASHRAE) recommends a ventilation rate of 0.35 ach (air changes per hour) for new homes, and some new homes are being built to even more stringent specifications. In such homes, special care must be taken to ensure that high concentrations of indoor air pollutants do not accumulate.

Here are some key actions that can make a difference:

Use radon-resistant construction techniques.

Get a copy of the EPA brochure,Model Standards and Techniques for Radon Control in New Homes, of youState Radon Agencyor the health authority, state homebuilders association, or EPA regional office.

Choose building materials and furnishings that minimize indoor air pollution.

There are many steps a homeowner can take to select products that will prevent indoor air problems from occurring, some of which are listed here. First, use exterior hardboard products made with phenol-formaldehyde resin on floors, cabinets, and wall surfaces. Or alternatively, consider using solid wood products. Second, if you plan to install carpet over ground-contact concrete, especially basement concrete, be sure to install an effective moisture barrier before laying the carpet. Do not permanently glue the mat to the concrete with adhesives so the mat can be removed if it gets wet.

For new construction, provide adequate drainage and seal the foundation.

The air that enters the house through the foundation can contain more moisture than is generated by all the activities of the occupants.

Familiarize yourself with mechanical ventilation systems and consider installing one.

New advanced home designs are beginning to feature mechanical systems that bring outside air into the home. Some of these designs include energy efficient heat recovery fans (also known as air-to-air heat exchangers).

Make sure combustion appliances, including stoves, fireplaces, wood-burning stoves, and space heaters, are properly vented and have adequate airflow.

Combustion gases, including carbon monoxide, and particulates can be blown back into the living space from the chimney or chimney if the chimney is not properly vented or not getting a sufficient air supply. Crevices can be a particular problem in worn-out or heavily built-up homes. Installing a dedicated outside air supply to the combustion appliance can help prevent backflow.

DO YOU UNDERSTAND THAT YOUR OFFICE HAS AN INDOOR AIR PROBLEM?

Indoor air quality problems are not limited to homes. In fact, many office buildings have significant sources of air pollution. Some of these buildings may not be adequately ventilated. For example, mechanical ventilation systems may not be designed or operated to provide adequate amounts of outside air. Finally, people often have less control over the indoor climate in their offices than they do at home. As a result, the frequency of reported health problems has increased.

health effects

Several well-identified diseases, such as Legionnaires' disease, asthma, hypersensitivity pneumonitis, and wet fever, have been directly linked to specific construction problems. These are known as construction-related diseases. Most of these diseases are treatable, but some carry serious risks.

However, sometimes building occupants experience symptoms that do not fit the pattern of a specific disease and are difficult to trace back to a specific cause. This phenomenon is known as 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; Sneeze; stuffy or runny nose; tiredness or lethargy; Headache; Dizziness; nausea; irritability and forgetfulness. Poor lighting, noise, vibration, thermal discomfort, and psychological stress can also cause or contribute to these symptoms.

There is no one way for these health problems to occur. In some cases, the problems begin when employees enter their offices and subside when employees leave; In other cases, symptoms persist until the condition is treated. Sometimes many workers in a building have bouts of illness; in other cases, health symptoms appear only in individual workers.

According to some experts from the World Health Organization, up to 30% of new or converted commercial buildings may experience unusual levels of occupant health and comfort issues that may be related to indoor air quality.

What causes problems?

The three main reasons for poor indoor air quality in office buildings are the presence of sources of indoor air pollution; poorly designed, maintained or operated ventilation systems; and uses of the building that were unforeseen or poorly planned in the design or renovation of the building.

Sources of air pollution in the office

As in homes, the most important factor affecting indoor air quality is the presence of polluting sources. Common office pollutants and their sources include environmental tobacco smoke; Asbestos for insulating and fireproof building materials; formaldehyde from hardboard products; other organic matter from building materials, carpets and other office furniture, cleaning materials and activities, bathroom fresheners, paints, adhesives, photocopiers, and photographic and printing facilities; Biological contaminants from dirty ventilation systems or water-damaged walls, ceilings, and carpets; and pesticides from pest control practices.

ventilation system

Mechanical ventilation systems in large buildings are not only designed and function to heat and cool air, but also to draw in and circulate outdoor air. However, when ventilation systems are poorly designed, operated, or maintained, they can contribute to indoor air problems in many ways.

Problems arise, for example, when ventilation systems do not provide enough outside air to save energy. Inadequate ventilation also occurs when the air supply and exhaust openings in each room are blocked or positioned so that outside air does not actually reach the breathing zone of the building occupants. Poorly positioned external air intakes can also bring in air contaminated with car and truck exhaust, boiler emissions, smoke from rubbish bins, or air from bathrooms. Finally, the ventilation systems themselves can be a source of indoor fouling, spreading biological contaminants that have multiplied in cooling towers, humidifiers, dehumidifiers, air conditioning units, or on the inside surfaces of ventilation ducts.

building use

Indoor air pollutants can flow into offices in the same building from parts of the building that are used for specific purposes, such as restaurants, print shops, and dry cleaners. Carbon monoxide and other components of automobile exhaust can be transported into offices from underground parking garages via stairways and elevator shafts.

Additionally, buildings originally designed for a specific purpose may end up being converted for use as offices. If not properly modified during building renovation, partitions and the ventilation system can contribute to indoor air quality problems by restricting air circulation or providing an insufficient supply of outdoor air.

What to do if you suspect a problem

If you or others in your office have health or comfort issues that you suspect are caused by indoor air pollution, here are some things you can do:

• Talk to other workers, your manager, and union representatives to see if others are experiencing the same problems, and ask management to keep a record of reported health conditions if they haven't already.
• Talk to your own doctor and report your concerns to the company doctor, nurse or health and safety officer.
• Call your local or state health department or air pollution control agency to discuss symptoms and possible causes.
• Encourage building managers to obtain a copy of EPA's Building Air Quality: A Guide for Building Owners and Facility Managers. Building Air Quality (BAQ) is written simply, but provides comprehensive information on how to identify, correct, and prevent indoor air quality problems. BAQ also provides support information, e.g. For example, when and how to select outside technical support, how to communicate with others about indoor air problems, and where to find additional sources of information. To receive the loose-leaf version of Indoor Air Quality with appendices, an index, and a full set of helpful forms, as well as the recently released Indoor Air Quality Action Plan, request GPO Stock Number 055-000- 00602-4, for $28, contact Contact: Superintendent of Documents, U.S. Government Press Office (GPO), P.O. Box 371954, Pittsburgh, PA 15250-7954, or by phone (202) 512-1800, fax (202) 512-2250.
• Get a copy of"Office Resident's Guide to Indoor Air Quality",EPA-402-K-97-003, October 1997 from IAQ INFO at 1-800-438-4318.
• Often, indoor air quality problems in large commercial buildings cannot be effectively identified or resolved without a comprehensive building inspection. These investigations may begin with written questionnaires and telephone inquiries, during which building investigators assess the occupants' symptom history and building operating procedures. In some cases, these investigations can quickly reveal the problem and on-site visits are unnecessary.
• More often, however, investigators must enter the building to conduct face-to-face interviews with residents, look for possible causes of problems, and inspect the design and operation of the ventilation system and other building features. Because measuring contaminants at the very low levels commonly found in office buildings is expensive and may not provide useful information for identifying sources of problems, many measurements may not be made by researchers. The process of resolving indoor air quality issues that result in health and comfort complaints can be time consuming and involve much trial and error before successful corrective actions are identified.
• When hiring a professional firm to conduct a building survey, select a firm based on their experience identifying and solving indoor air quality problems in non-industrial buildings.
• Work with others to develop a smoking policy that eliminates the unintentional exposure of non-smokers to environmental tobacco smoke.
• For information on obtaining a health hazard assessment at your office (800-35NIOSH), call the National Institute for Occupational Safety and Health (NIOSH) or contact the Occupational Safety and Health Administration, (202) 219- 8151.

REFERENCE GUIDE TO THE MAIN INTERNAL POLLUTANTS IN THE HOME

The contaminants listed in this guide have been shown to have the listed health effects. However, it is not necessarily correct that the observed effects occur at typical concentrations of household pollutants. In many cases, our understanding of contaminants and their health effects is too limited to determine the levels at which the listed effects may occur.

RADON (Rn)

Origins:dirt and rock under the house; well water; Construction materials.

Health Effects:No immediate symptoms. It is estimated that between 7,000 and 30,000 deaths from lung cancer occur each year. Smokers are at increased risk of developing radon-induced lung cancer.

House levels:Based on a 1991 National Residential Radon Survey, the average indoor radon level is 1.3 picocuries per liter (pCi/L). The average value in open air is about 0.4 pCi/L.

Steps to reduce exposure:

• Testing your home for radon_it's easy and inexpensive.
• Repair your home if your radon level is 4 picocuries per liter (pCi/L) or higher.
• Radon levels below 4 pCi/L still pose a risk and, in many cases, can be reduced.
• For more information about radon, contact your state radon agency or call 800-SOS-RADON.

ENVIRONMENTAL TOBACCO SMOKE (ETS)

Those:Smoking cigarettes, pipes and cigars.

Health Effects:eye, nose and throat irritation; Headache; Lung cancer; can contribute to heart disease. Increased risk of lower respiratory tract infections, such as bronchitis and pneumonia, and ear infections, particularly in children; fluid buildup in the middle ear; increased severity and frequency of asthma attacks; decreased lung function.

House levels:Particle levels in homes without smoke or other strong sources of particulates are the same as or lower than outdoors. In homes with one or more smokers, particulate levels can be many times higher than outside.

Steps to reduce exposure:

• Don't smoke in your home and don't let other people smoke.
• Do not smoke in the presence of children, especially babies and young children.
• If indoor smoking cannot be avoided, increase ventilation in the smoking area. Open windows or use exhaust fans.

BIOLOGY

Origins:Wet or damp walls, ceilings, carpets, and furniture; poorly maintained humidifiers, dehumidifiers, and air conditioners; Pijama; pets.

Health Effects:eye, nose and throat irritation; Shortness of breath; Dizziness; Lethargy; Fever; digestive problems. It can cause asthma; humidifier fever; Flu and other infectious diseases.

House levels:Pollen and mold concentrations indoors are lower than outdoors (unless there are sources of fungus indoors). The concentration of dust mites inside is higher than outside.

Steps to reduce exposure:

• Install and use outdoor exhaust fans in kitchens and bathrooms.
• Vent the dryer to the outside.
• Clean ultrasonic and cool mist humidifiers according to manufacturer's instructions and refill with clean water daily.
• Frequently empty the water trays in air conditioners, dehumidifiers, and refrigerators.
• Clean and dry or remove water damaged rugs.
• Use basements as living quarters only if they are closed and adequately ventilated. If necessary, use dehumidifiers to keep the humidity between 30 and 50 percent.

CARBON MONOXIDE (CO)

Origins:ventless gas and kerosene heaters; leaky chimneys and furnaces; removal of stoves, water heaters, wood stoves and fireplaces; gas stoves Escape the car from the attached garages. Environmental tobacco smoke.

Health Effects:At low levels, fatigue in healthy people and chest pain in people with heart disease. At higher concentrations, visual and coordination disturbances; Headache; Dizziness; Confusion; nausea. It can cause flu-like symptoms that go away after you leave the house. Deadly in very high concentrations.

House levels:Average levels in homes without a gas stove range from 0.5 to 5 parts per million (ppm). Levels close to correctly set gas ranges are typically 5-15 ppm and those near poorly set ranges can be 30 ppm or higher.

Steps to reduce exposure:

• Keep gas appliances properly adjusted.
• Consider purchasing a vented heater if you are replacing a non-vented one.
• Use the proper fuel in kerosene space heaters.
• Install and use a range hood that extends over gas stoves.
• Open flues if chimneys are used.
• Choose the right size wood stoves that are certified to meet EPA emissions standards. Make sure all doors to the wood stove are securely closed.
• Have your central heating system (stoves, ducts, and chimneys) inspected, cleaned, and adjusted annually by a qualified professional. Fix any leaks immediately.
• Do not leave the car parked in the garage.

NITROGEN DIOXIDE (NO2)

Origins:Oil heaters, ventless gas stoves and space heaters. Environmental tobacco smoke. Health Effects: Irritation of eyes, nose and throat. It can affect lung function and increase respiratory infections in young children.

House levels:The average level in homes without combustion appliances is approximately half that outside. In homes with gas stoves, kerosene heaters, or ventless gas heaters, indoor levels often exceed outdoor levels.

Steps to reduce exposure:See steps in Carbon Monoxide.

ORGANIC GASES

Origins:Household products including: paints, strippers and other solvents; wood preservatives; aerosol sprays; cleaning and disinfection products; moth repellents and air fresheners; stored fuels and automotive products; hobby supplies; dry clean clothes.

Health Effects:eye, nose and throat irritation; headache, loss of coordination, nausea; Damage to the liver, kidneys and central nervous system. Some organic substances can cause cancer in animals; some are suspected or known to cause cancer in humans.

House levels:Studies have shown that indoor levels of various organic matter are, on average, 2 to 5 times higher than outdoor levels. During and for several hours immediately after certain activities, such as

Steps to reduce exposure:

• Use household products according to the manufacturer's instructions.
• Provide plenty of fresh air when using these products.
• Safely dispose of unused or barely used containers; Buy in quantities that you will use soon.
• Keep out of the reach of children and pets.
• Never mix household care products unless directed to do so on the label.

ATEMBARE PARTIKEL

Origins:Fireplaces, wood stoves and kerosene heaters. Environmental tobacco smoke.

Health Effects:eye, nose and throat irritation; respiratory infections and bronchitis; Lung cancer. (Effects attributable to environmental tobacco smoke are listed elsewhere.)

House levels:Particle levels in homes without smoke or other strong sources of particulates are at or below outdoor levels.

Steps to reduce exposure:

• Vent all ovens; Keep doors to the rest of the house open when using ventless heaters.
• Choose the right size wood stoves that are certified to meet EPA emissions standards; Make sure all doors to the wood stove are securely closed.
• Have your central heating system (stove, ducts, and chimneys) inspected, cleaned, and adjusted annually by a qualified professional. Fix any leaks immediately.
• Change filters in central heating and cooling systems and air cleaners according to manufacturer's instructions.

FORMAT SKIN

Origins:Compressed wood products (hardwood plywood carpeting, particle board, fiberboard) and furniture made from these compressed wood products. Urea formaldehyde foam insulation (UFFI). Combustion sources and tobacco smoke in the area. Durable pressed fabrics, other textiles, and adhesives.

Health Effects:eye, nose and throat irritation; wheezing and coughing; Fatigue; Rash; severe allergic reactions. It can cause cancer. May also cause other effects listed under "organic gases".

House levels:Average concentrations in older homes without UFFI are generally well below 0.1 (ppm). In homes with significant amounts of new particleboard products, levels can exceed 0.3 ppm.

Steps to reduce exposure:

• Use "outdoor" agglomerate products (fewer emissions as they contain phenolic resins and not urea resins).
• Use air conditioners and dehumidifiers to maintain a moderate temperature and reduce humidity.
• Increase ventilation, especially after bringing new sources of formaldehyde into the home.

PESTICIDES

Origins:Products used to kill household pests (insecticides, termiticides and disinfectants). Also products used on lawns and gardens that are drifting or tracked indoors.

Health Effects:eye, nose and throat irritation; damage to the central nervous system and kidneys; increased risk of cancer.

House levels:Preliminary surveys indicate a widespread presence of pesticide residues in homes.

Steps to reduce exposure:

• Use strictly in accordance with the manufacturer's instructions.
• Mix or dilute outdoors.
• Apply only in the recommended amounts.
• Increase ventilation when used indoors. Take plants or pets outside if you apply pesticides to them.
• Use non-chemical pest control methods whenever possible.
• If you hire a pest control company, select it carefully.
• Don't store unnecessary pesticides indoors; Safely dispose of unused containers.
• If possible, store clothes with moth repellent in separately ventilated rooms.
• Keep indoor spaces clean, dry, and well ventilated to avoid pest and odor problems.

ASBESTOS

Origins:Deteriorated, damaged or broken insulation, fire protection, acoustic materials and tiles.

Health Effects:No immediate symptoms but long-term risk of breast and abdominal cancer and lung disease. Smokers are at increased risk of developing asbestos-induced lung cancer.

House levels:Elevated levels can occur in homes where asbestos-containing materials are damaged or disturbed.

Steps to reduce exposure:

• It is best to leave asbestos material intact when it is not likely to be disturbed.
• Use contractors who are trained and qualified for asbestos control and cleanup.
• Follow proper procedures when replacing door seals on wood stoves that may contain asbestos.

LEAD

Origins:Lead-based paint, contaminated soil, dust, and drinking water.

Health Effects:Lead affects virtually every system in the body. Lead in high concentrations (lead concentrations up to 80 micrograms per deciliter (80 ug/dl) of blood) can cause seizures, coma, and even death. Lower lead levels can have adverse effects on the central nervous system, kidneys, and blood cells. Blood lead levels as low as 10 ug/dl can affect mental and physical development.

Steps to reduce exposure:

• Keep areas where children play as dust-free and clean as possible.
• Leave lead-based paint intact if it is in good condition; Do not open or burn paint that may contain lead.
• Do not remove lead paint yourself.
• Do not bring lead dust home.
• If your job or hobby involves lead, change your clothes and use rugs before you go home.
• Eat a balanced diet rich in calcium and iron.

Where to get additional information on indoor air quality

Links to other federal agencies on this page are references to other servers and locations on the Internet. This information is provided here as a service.

Federal sources of information on indoor air quality

Federal agencies with information on indoor air quality can be contacted as follows:

US Environmental Protection Agency (US EPA)

INDOOR AIR QUALITY - Information Center (IAQ INFO)
PO Box 37133
Washington, DC 20013-7133
(800) 438-4318; (703) 356-4020
(Fax) 703-356-5386the email:iaqinfo@aol.com
Open from Monday to Friday from 9 am. at 5 p.m. m., Eastern Standard Time (EST). Distributes EPA publications, answers telephone inquiries, and makes recommendations to other government and nonprofit organizations.

NATIONAL RADON HOTLINES
(800) SOS-RADON
[(800) 767-7236]
The information registry works 24 hours a day.

LEADING NATIONAL INFORMATION CENTER
(800) PLOMO-FYI
[(800) 532-3394]
Operation 24 hours a day, seven days a week. Callers can request an information packet. To speak with an information specialist, call (800) 424-5323. Open Monday through Friday from 8:30 a.m. until 5 pm EUROPEAN SUMMER TIME.

NATIONAL TELECOMMUNICATIONS NETWORK FOR PESTICIDES
National toll-free number:(800) 858-PEST
[Me Oregon - (800) 858-7378]
Open Monday through Friday from 6:30 a.m. at 4:30 p.m. m., Pacific time. Provides pesticide information to the general public and the medical, veterinary, and professional communities. Medical and government personnel can call 800-858-7377.

RCRA/SUPERFUND HOTLINE
National toll-free number:(800) 424-9346
In the Washington, DC area: (703) 412-9810
Open Monday through Friday from 8:30 a.m. until 19.30 EUROPEAN SUMMER TIME. Provides information on the regulations of the Resource Conservation and Recovery Act (including solid and hazardous waste issues) and the Superfund Act.

SAFE DRINKING WATER HOTLINE
(800) 426-4791
Open Monday through Friday from 8:30 a.m. until 5 pm EUROPEAN SUMMER TIME. Provides information on Safe Drinking Water Act regulations, lead and radon in drinking water, information on filtration, and a list of state drinking water agencies.

TSCA SUPPORT INFORMATION SERVICE
(202) 554-1404
Open Monday through Friday from 8:30 a.m. until 5 pm EUROPEAN SUMMER TIME. Provides information on Toxic Substances Control Act regulations and EPA's Asbestos Program.

US Consumer Product Safety Commission (CPSC)

US Department of Housing and Urban Development

Office of Energy and Environment, Washington, DC 20410
HUD USER National Toll Free Number: (800) 245-2691
In the Washington, DC area: (301) 251-5154

US Department of Energy

Agency for the Conservation of Nature and Renewable Energy
1000 Independence Avenue, SW, Washington, DC 20585

Consultation and Recommendation Service for Conservation and Renewable Energies (CAREIRS)
Postfach 3048, Merrifield, VA 22116; (800) 523-2929.
Open Monday through Friday, 9 am to 5 pm EST. Provides consumer information on energy savings and renewable energy in homes.

US Health Service

Department of Occupational Medicine of the Federal Government
Department of Environmental Health, Region III, Room 1310
3535 Market Street, Philadelphia, PA 19104
(215) 596-1888; Fax: 215-596-5024
Provides indoor air quality consulting services to federal agency leaders.

Centers for Disease Control and Prevention

Lead Poisoning Prevention Unit
Centers for Disease Control and Prevention
4770 Buford Highway, NE (F-42)
Atlanta, Georgia 30341-3724
(800) 488-7330

Secretary of Tobacco and Health
Centers for Disease Control and Prevention
4770 Buford Highway, Nebraska (K-50)
Atlanta, Georgia 30341-3724
(404) 488-5701

Occupational Health and Safety Authority(OSHA)

Consumer Information and Defense Office
Raum N-3647, 200 Constitución Avenue, NW
Washington, DC 20210
(202) 219-8151

Bonneville Energieverwaltung

Portland, Oregon 97208

General Services Management

18th and E Streets, NW
Washington, DC 20405

Tennessee Valley Authority

Industrial Hygiene Department
Multi-Use Building (1-B)
Muscle Swarms, AL 35660

State and local organizations

Your state or local government agency can answer your questions or concerns about indoor air problems. Responsibilities for indoor air quality problems are typically divided among many different agencies. Calling or writing government agencies responsible for health or air quality control is the best way to obtain information from your state or local government. We obtainGovernment Agency Contacts, write or call EPAIndoor Air Quality Information Center, (800) 438-4318, (703) 356-4020 in the Washington, DC area.

Other Organizations

The following organizations have information specifically covered in this brochure. Call to...Indoor Air Quality Information Centerat (800) 438-4318 for the names of various organizations that have more information on specific and general indoor air quality issues.

American Association of Poison Control Centers (AAPCC)
3800 Embalse Road, NW
Washington, DC 20007
Webistas:www.aapcc.org

Association of Home Appliance Manufacturers (AHAM)
20 North Wacker Drive
Chicago, 60606
(312) 984-5800, ext. 308
Website:www.aham.org

American Society for Heating, Refrigeration, and Air-Conditioning (ASHRAE)
1791 Tullie-Bred NO
Atlanta, GA30329
Website:www.ashrae.org

World Health Organization (WHO)
launch center
Avenida Sheridan, 49
Albany, New York 12210
Website:www.who.org

Un local de la American Lung Association (ALA)
ALA National Headquarters
1740 Broadway
New York, New York 10019
(800) LUNG-EE.UU.
Website:www.lungusa.org

Glossary of terms

• ACID SPRAY: Acidic liquid or solid particles small enough to be transported by air. High levels of acidic aerosols can irritate the lungs and have been linked to some respiratory diseases, including asthma.
• animal's hair: Tiny scales of animal skin.
• ALLERGEN: A substance that can cause an allergic reaction due to a person's sensitivity to that substance.
• REVERSIBLE ALLERGICS: Inflammation of the lining of the nose caused by an allergic reaction.
• CONSTRUCTION RELATED ILLNESS: A discrete and identifiable illness or disease that can be attributed to a specific contaminant or source within a building. (Opposite of "Sick Building Syndrome").
• CHEMICAL SENSITIZATION: There is evidence that some people may develop health problems characterized by effects such as dizziness, eye and throat irritation, chest tightness, and nasal congestion that occur when exposed to certain chemicals. People can even react to trace amounts of chemicals to which they have been "sensitized."
• ENVIRONMENTAL TOBACCO SMOKE (ETS): Mixture of smoke from the burning end of a cigarette, pipe, or cigar and the smoke exhaled by the smoker (also known as passive smoking or secondhand smoke).
• MUSHROOMS: Any of a group of lower parasitic plants lacking chlorophyll, including fungi and molds.
• HUMIDIFIER FEVER: Respiratory disease caused by exposure to toxins from microorganisms found in wet or humid areas in humidifiers and air conditioners. Also called air conditioning or ventilation fever.
• HYPERSENSITIVITY PNEUMONITIS: A group of respiratory diseases that cause inflammation of the lungs (especially granulomatous cells). Most forms of hypersensitivity pneumonitis are caused by breathing in organic dusts, including mold.
• ORGANIC COMPOUNDS: Chemicals that contain carbon. Volatile organic compounds evaporate at room temperature and pressure. They can be found in many indoor sources, including many common household products and building materials.
• PICOCURIA (pCi): A unit of measurement for radioactivity, often expressed in picocuries per liter (pCi/L) of air.
• PRESS WOOD PRODUCTS: A group of materials used in the construction and manufacture of furniture, consisting of wood veneers, particles, or fibers held together by an adhesive under heat and pressure.
• RADONIUM (Rn) AND PRODUCTS OF DESTRUCTION OF RADONIUM: Radon is a radioactive gas produced when uranium decays. Radon decay products (also called radon progeny or progenitors) can be aspirated into the lungs, where they continue to release radiation as they continue to decay.
• SICK BUILDING SYNDROME: Term that refers to a set of symptoms that affect a certain number of building occupants during the time they are in the building and that decrease or disappear when they leave the building. It cannot be attributed to specific contaminants or sources within the building. (As opposed to "building-related illness").
• VENTILATION RATE: The speed at which indoor air enters and leaves a building. Expressed in two ways: the number of outside air changes per unit time (air changes per hour or "ach"), or the rate at which a volume of outside air enters per unit time (cubic feet per minute or "cfm" ).
• CPSC and EPA have not reviewed or approved all of the information and documents on indoor air quality that may be provided by other groups or organizations.