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Frequently Asked Air Questions

Following are some of the most common questions that are asked by our web site visitors. If you don't find the answer that you need below, then you can submit your question to us by telephone, mail, email, or web form via our Contact Us page.

Find Questions by Subject List

  1. Administrative Questions
  2. Acid Rain
  3. Air Pollution
  4. Air Pollution Complaints
  5. Air Toxics (Hazardous Air Pollutants) 
  6. Asthma
  7. Carbon Monoxide
  8. Criteria Air Pollutants
  9. Diesel Particulate Matter
  10. Indoor Air Quality
  11. NAAQS
  12. Nitrogen Oxides
  13. Ozone (Smog)
  14. Particulate Matter
  15. Pollution Prevention
  16. Radiation
  17. Ultra-low sulfur diesel fuel
  18. Vehicles, Engines and Fuels

Administrative Questions

Q: What states make up Region 3?

A: EPA Region 3 consists of the states of:

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Q: Who should I contact about air pollution problems?

A: While the Region 3 office oversees the 6 mid-Atlantic state area, these states have the first line of responsibility for air, water and waste issues in their states. Each state has its own environmental agency.  The two largest local agencies in Region 3 are listed also.

Their phone numbers are:

Delaware 800-662-8802
District of Columbia 202-535-2250
Maryland 410-631-3215 or 410-243-8700
Pennsylvania 800-541-2050
Virginia 800-592-5482
West Virginia 304-926-3647
Allegheny County (PA) 412-687-ACHD
Philadelphia, PA (215) 685-7580

You may also submit a complaint or tip to EPA via our Citizen Tip/Complaint Form. Please note, however, that your first point of contact for any air pollution complaint (or tip) should be the appropriate state or local air quality agency listed above since these agencies have primary responsibility under the Clean Air Act for enforcement of air quality regulations within their jurisdiction(s). You may also contact the above agencies on the web through our State & Local Air Quality Agencies contact page.

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Q: How can I order EPA publications?

A: Many EPA publications are available free-of-charge from the National Service Center for Environmental Publications (NSCEP, formerly NCEPI), which is located in Cincinnati, OH. To order publications, call NSCEP toll-free at 1-800-490-9198. To search a catalog of EPA publications, and for further information about EPA publications, visit NSCEP's web site.

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Q: How can I locate the phone numbers and mailing addresses of EPA staff people?

A: EPA's automated National Employee Directory contains the telephone numbers of most EPA employees and associated contractors. You can search the directory by the name of the employee. The main mailing address for EPA nationally is:

Environmental Protection Agency
401 M St, SW
Washington, DC 20460

To send a letter to a certain person, you would need to add their name, and the appropriate mail code (listed in the National People Locator) for the employee's office to the above address.

Key Region 3 phone numbers are available. The mailing address for EPA Region 3 is:

Environmental Protection Agency
Region 3
1650 Arch Street
Philadelphia, PA  19103-2029

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Q: How do I report a violation of environmental regulations?

A: State and local governments have responsibility for enforcing most environmental laws in the area where you live. You can locate these government offices through your telephone directory. In most communities, the responsible agency is the city or county health department. At the state level, an environmental agency carries out the pollution control laws, whereas an agriculture agency often handles regulation of pesticides. If these sources can't help you, contact EPA Region 3.

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Q: How can I report an environmental emergency?

A: Environmental emergencies such as oil and chemical spills should be reported immediately to the National Response Center at 1-800-424-8802 or contact EPA Region 3's Response Center at 215-814-9016 or our Superfund Hotline at 800-553-2509.  For more information on environmental emergencies, visit EPA's Concerned Citizens' Environmental Emergencies page.

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Q: How can I find out about job openings and internships at the EPA?

A: The Office of Human Resources and Organizational Services is the key contact for all employment information within the EPA. However, job information is not contained centrally on the EPA Internet server, but is instead maintained by the Federal Office of Personnel Management (OPM). Exit EPA Click for disclaimer OPM offers information about all federal jobs that fit specific qualifications, and will soon be searchable by specific Agencies or Departments.

EPA offers several opportunities for internships. You can find information on these opportunities from the Office of Human Resources and Organizational Services students web site.

You may also wish to contact EPA Region 3 directly for information about employment and internship opportunities in the mid-Atlanitic region.

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Q: How can I submit an official comment on proposed environmental regulations?

A: Comments on proposed rules should be submitted to the EPA docket for the regulatory area that oversees the rule. Many dockets accept comments via e-mail. Consult our list of EPA dockets for the address, telephone number and e-mail address for the docket you may wish to contact.

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Q: How do EPA's rules and policies affect small business?

A: EPA has many assistance programs for small business and provides information with the small business entrepreneur in mind. The Small Business Gateway offers complete information about regulations and policies that relate to small business.

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Air Pollution

Q: What is air pollution?

A: Air pollution is the contamination of air by the discharge of harmful substances. Air pollution threatens the health of human beings and other living things on our planet. While often invisible, pollutants in the air create smog and acid rain, cause cancer or other serious health effects, diminish the protective ozone layer in the upper atmosphere, and contribute to the potential for world climate change. Since polluted air can move from one area or region to another, it has the potential to affect virtually all of us. Air pollution can cause health problems including burning eyes and nose, itchy irritated throat, respiratory problems, aggravate heart and respiratory problems. Above certain concentration and durations, certain air pollutants are extremely dangerous and can cause severe injury or death. Level, extent, and duration of exposure, age, individual susceptibility and other factors play a significant role in determining whether or not someone will experience pollution-related health problems. Air pollution also can result in haze, which reduces visibility in national parks and elsewhere, and can sometimes interfere with aviation. Air pollution can also damage the environment and property.

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Q: What are criteria air pollutants?

A: The Clean Air Act established two types of national air quality standards. "Primary" standards are designed to establish limits to protect public health, including the health of "sensitive" populations such as asthmatics, children, and the elderly. "Secondary" air quality standards set limits to protect public welfare, including protection against decreased visibility and damage to animals, crops, vegetation, and buildings.

EPA has set national air quality standards for six principal pollutants (referred to as "criteria" pollutants): carbon monoxide (CO), lead (Pb), nitrogen dioxide (NO2), ozone (O3), particulate matter (PM), and sulfur dioxide (SO2). [Note: The pollutant ozone is not emitted directly into the air, but is formed when sunlight acts on emissions of nitrogen oxides (NOx) and volatile organic compounds (VOC).]

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 Q: What are the sources of air pollution?

A: Air pollution has many sources. Some sources are obvious- like industrial smokestacks, chemical plants, automobiles, trucks and buses. Others are not so obvious- like gasoline stations; dry-cleaners; outboard motors; lawn, garden, farm and construction equipment engines; certain paints; and various household products.

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Acid Rain

Q: What is acid rain?

A: Acid rain is rain that is more acidic than normal. Sulfur dioxides (SO2) and nitrogen oxides (NOx) produced by the burning of fossil fuels are the major cause of acid rain. SO2 and NOx combine with moisture in the air to form acid rain. Acid rain causes acidification of lakes and streams and contributes to damage of trees at high elevations. In addition, acid rain accelerates the decay of building materials and paints, including irreplaceable buildings, statues, and sculptures that are part of our nation's cultural heritage. For more information, see the Mid-Atlantic Acid Rain Program Page.

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Air Toxics/Hazardous Air Pollutants (HAPs)

Q: What are toxic (hazardous) air pollutants?

A: Toxic air pollutants (or Hazardous Air Pollutants, HAPs) are a subset of air pollutants. Air toxics are known or suspected to cause cancer or other serious heath effects, such as damage to respiratory or nervous systems. Toxic air pollutants may exist as particulate matter or as vapors (gases). Air toxics include metals, particles, and certain vapors from fuels and other sources. To find out more about toxic air pollutants visit our Air Toxics in the Mid-Atlantic States web page or EPA's "about air toxics" page. Also check out EPA's National Air Toxics Assessment (NATA) website.

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Indoor Air Quality

Q: What causes indoor air quality problems and how can I tell whether I have a problem?

A: Indoor pollution sources that release gases or particles into the air are the primary cause of indoor air quality problems in homes. Inadequate ventilation can increase indoor pollutant levels by not bringing in enough outdoor air to dilute emissions from indoor sources and by not carrying indoor air pollutants out of the home. High temperature and humidity levels can also increase concentrations of some pollutants. EPA has developed a Building Survey to help you determine if there's a problem.

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Q: What is Ozone (O3)?

A: Ozone is a gas that forms in the atmosphere when 3 atoms of oxygen are combined. It is not emitted directly into the air, but at ground level is created by a chemical reaction between oxides of nitrogen (NOx), and volatile organic compounds (VOC) in the presence of sunlight. Ozone has the same chemical structure whether it occurs high above the earth or at ground level and can be "good" or "bad", depending on its location in the atmosphere.

Q: How can Ozone be both "good" and "bad"?

A: Ozone occurs in two layers of the atmosphere. The layer surrounding the earth's surface is the troposphere. Here, ground-level or "bad" ozone is an air pollutant that damages human health, vegetation, and many common materials. It is a key ingredient of urban smog. The troposphere extends to a level about 10 miles up, where it meets the second layer, the stratosphere. The stratospheric or "good" ozone layer extends upward from about 10 to 30 miles and protects life on earth from the sun's harmful ultraviolet rays (UV).

Ozone is "Good up high, bad nearby."

Q: What is happening to the "good" ozone layer?

A: Ozone occurs naturally in the stratosphere and is produced and destroyed at a constant rate. But this "good" ozone is gradually being destroyed by manmade chemicals called chlorofluorocarbons (CFCs), halons, and other ozone depleting substances (used in coolants, foaming agents, fire extinguishers and solvents). These ozone depleting substances degrade slowly and can remain intact for many years as they move through the troposphere until they reach the stratosphere. There they are broken down by the intensity of the sun's ultraviolet rays and release chlorine and bromine molecules, which destroy 'good" ozone. One chlorine or bromine molecule can destroy 100,000 ozone molecules, causing ozone to disappear much faster than nature can replace it.  It can take years for ozone depleting chemicals to reach the stratosphere, and even though we have reduced or eliminated the use of many CFCs, their impact from years past is just starting to affect the ozone layer. Substances released into the air today will contribute to ozone destruction well into the future.  Satellite observations indicate a world-wide thinning of the protective ozone layer. The most noticeable losses occur over the North and South poles because ozone depletion accelerates in extremely cold weather conditions.

Q: How does the depletion of "good" ozone affect human health and the environment?

A: As the stratospheric ozone layer is depleted, higher UV levels reach the earth's surface. Increased UV can lead to more cases of skin cancer, cataracts, and impaired immune systems. Damage to UV sensitive crops, such as soybeans, reduces yield. High altitude ozone depletion is suspected to cause decreases in phytoplankton, a plant that grows in the ocean. Phytoplankton is an important link in the marine food chain, and therefore, food populations could decline.

The ozone depletion web site explains EPA's programs to protect the ozone layer and other information related to ozone depletion. In particular, the ozone science page offers much more detail on ozone depletion, its causes and effects, and what the world is doing to fix the problem.

Q: What is being done about the depletion of good ozone?

A: The Montreal Protocol, a series of international agreements on the reduction and eventual elimination of production and use of ozone depleting substances, became effective in 1989. Currently, 160 countries participate in the Protocol. Efforts will result in recovery of the ozone layer in about 50 years.

In the US, the EPA continues to establish regulations to phase out these chemicals. The Clean Air Act requires warning labels on all products containing CFCs or similar substances, prohibits nonessential ozone depleting products, and prohibits the release of refrigerants used in car and home air conditioning units and appliances into the air.

Q: What is "bad" ozone?

A: The same ozone molecules that protect us from UV high in the stratosphere can cause health problems for people and animals when they form near the earth's surface. Ground-level ozone is manmade, much of it created by you and me. Ground-level ozone is formed when volatile organic compounds (VOCs) and nitrogen oxides (NOx) react in the presence of sunlight. VOCs and NOx emissions come from motor vehicle exhaust, household products, dry cleaning, printing industries, gasoline storage tanks, solvents, aerosol sprays, paints and are produced by burning coal.

Q: How does "bad" ozone affect human health and the environment?

A: Repeated exposure to ozone pollution may cause permanent damage to the lungs. Even when ozone is present in low levels, inhaling it triggers a variety of health problems including coughing, throat irritation, and tightness in the chest.  It also can worsen bronchitis, heart disease, emphysema, and asthma, and reduce lung capacity. Children, the elderly and persons with lung disease are most affected, but even health adults can suffer these adverse effects. Because ozone pollution usually forms in hot weather, anyone who spends time outdoors in the summer may be affected. Ground level ozone also damages trees, plants, crops and reduces visibility. EPA's ozone mapping site provides information on ozone levels in many US cities. If you hear an ozone alert on the news, it means ozone levels in your area are very high that day, and you should try to stay indoors and not exercise vigorously until ozone levels drop again. EPA has several programs to reduce air pollution and ozone concentrations.

Q: What is an Ozone Action Day?

A: Certain cities with high levels of ground-level ozone have started programs called Ozone Action Days. The voluntary initiative was put in effect by a cooperative effort between government, environmental, and business organizations. The purpose of an Ozone Action Day is to alert the public that weather conditions are conducive to the formation of ozone. The public is asked to modify their behaviors to prevent contributing to the problem and to protect themselves from being exposed to and effected by the potential high ozone levels. Ozone is most often produced on summer days when the following two conditions exist: 1) there is little or no wind blowing and 2) temperatures are at or above 90 degrees Fahrenheit. When it is predicted that these conditions will exist on a given day, the public is alerted through television, newspaper and radio announcements.

Q: How can I reduce my contribution to Ground-Level Ozone?


Q: What are the National Ambient Air Quality Standards (NAAQS)?

A: Since the Clean Air Act's (CAA) inception in 1970, EPA has set NAAQS for six common air pollutants: carbon monoxide (CO), lead (Pb), nitrogen dioxide (NO2), ozone (O3), particulate matter with aerodynamic size less than or equal to 10 micrometers (PM-10), and sulfur dioxide (SO2). For these common air pollutants there are two types of pollution limits referred to as the primary and secondary standard. The primary standard is based on health effects; and the secondary standard is based on environmental effects such as damage to property, plants, and visibility. The CAA requires these standards be set at levels that protect public health and welfare with an adequate margin of safety. These standards allow the American people to assess whether or not the air quality in their communities is healthful. Also, the NAAQS present state and local governments with the air quality levels they must meet to achieve clean air. To find out more in-depth information about the criteria air pollutants, visit the Green Book site.

Q: What is the NAAQS for ozone?

A: The NAAQS for ozone is expressed in two forms which are referred to as the one-hour and eight-hour standards. Table 1 summarizes the ozone standards.


Standard Value (ppm = parts per million) Type Method of compliance
1-hour 0.12 ppm Primary and Secondary Concentration of ozone monitored in ambient air must not exceed standard value, on average, more than one day per year over any 3-year period
8-hour 0.08 ppm Primary and Secondary The 3-year average of the annual fourth highest daily maximum 8-hour average ozone concentration measured at each monitor within an area must be equal to or below the standard value

The one-hour ozone standard of 0.12 ppm has existed since 1979. The eight-hour ozone standard, which replaces the one-hour standard, was adopted by EPA on July 18, 1997 (62 FR 38856). However, the one-hour ozone standard continues to apply for existing nonattainment areas until such time as EPA determines that the area has attained the one-hour ozone standard (40 CFR 50.9(b)).

Q: What is an ozone nonattainment area?

A: It is an area that does not meet the NAAQS for ozone. Under section 181(a) of the Clean Air Act, each ozone nonattainment area was also classified by operation of law as "marginal," "moderate," "serious," "severe," or "extreme," depending on the severity of the area's air quality problem. The design value for a nonattainment area, which characterizes the severity of the area's air quality problem, is represented by the highest design value at any individual ozone monitoring site. The design value of a monitoring site is the fourth highest one-hour daily maximum ozone value recorded in a given three-year period with complete monitoring data. Table 2 provides the design value ranges for each nonattainment classification. These nonattainment designations and classifications were codified in 40 CFR Part 81 (see 56 FR 56694, November 6, 1991).


Marginal 0.121 up to 0.138 November 15, 1993
Moderate 0.138 up to 0.160 November 15, 1996
Serious 0.160 up to 0.180 November 15, 1999
Severe 0.180 up to 0.280 November 15, 2005
Extreme 0.280 and above November 15, 2010

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Particulate Matter (PM)

Q: What is Particulate Matter?

A: Particles found in the air we breathe, or "particulate matter" are a health concern in many areas. EPA has identified particles that are smaller than 10 microns (or 1/100 of a millimeter) as impacting human health. These particles, referred to as "PM10" become trapped in the lungs and cause irritation and injury to the lungs, worsen existing ailments, and can even cause death. There are many sources of particulate matter - fuel combustion, industrial practices and manufacturing, electric generation, waste disposal, wildfires, managed burning, fugitive dust, and crustal materials. Sources, particle size, and particle compositions vary extensively within a single area and between different areas.

In July 1997, EPA promulgated revised standards for particulate matter. Under these rules, EPA established a new particulate matter standard that specifically addresses particles smaller than 2.5 microns, or "PM2.5." The PM10 standard was retained. Both standards will provide continued reductions in particulate matter emissions in the future (the PM10 standard is 50 micrograms per cubic meter based on an annual average, and 150 micrograms per cubic meter on a 24 hour average; for PM2.5, it is 15 and 65, respectively). In addition, while PM10 tends to be a local problem, PM2.5 displays many characteristics different from larger particles, such as long distance transport.

Q: What is Diesel Particulate Matter?

A: Diesel particulate matter is part of a complex mixture that makes up diesel exhaust. Diesel exhaust is commonly found throughout the environment and is estimated by EPA's National Scale Assessment to contribute to the human health risk in the Mid-Atlantic region. Diesel exhaust is composed of two phases, either gas or particle and both phases contribute to the risk. The gas phase is composed of many of the urban hazardous air pollutants, such as acetaldehyde, acrolein, benzene, 1,3-butadiene, formaldehyde and polycyclic aromatic hydrocarbons. The particle phase also has many different types of particles that can be classified by size or composition. The size of diesel particulates that are of greatest health concern are those that are in the categories of fine, and ultra fine particles. The composition of these fine and ultra fine particles maybe composed of elemental carbon with adsorbed compounds such as organic compounds, sulfate, nitrate, metals and other trace elements. Diesel exhaust is emitted from a broad range of diesel engines; the on road diesel engines of trucks, buses and cars and the off road diesel engines that include locomotives, marine vessels and heavy duty equipment.

Q: How Do I Get Exposed to Diesel Particulate Matter?

A: The most common exposure pathway is breathing the air that contains the diesel particulate matter. The fine and ultra fine particles are respirable which means that they can avoid many of the human respiratory system defense mechanisms and enter deeply into the lung. Exposure to diesel particulate matter comes from both on road and off road engine exhaust that is either directly emitted from the engines or aged through lingering in the atmosphere.

Q: How Can Diesel Particulate Matter Affect My Health?

A: Diesel exhaust causes health effects from both short term or acute exposures and also long term chronic exposures, such as repeated occupational exposures. The type and severity of health effects depends upon several factors including the amount of chemical you are exposed to and the length of time you are exposed. Individuals also react differently to different levels of exposure. There is limited information on exposure to just diesel particulate matter but there is enough evidence to indicate that inhalation exposure to diesel exhaust causes acute and chronic health effects.

Acute exposure to diesel exhaust may cause irritation to the eyes, nose, throat and lungs, some neurological effects such as lightheadedness. Acute exposure may also elicit a cough or nausea as well as exacerbate asthma. Chronic exposure in experimental animal inhalation studies have shown a range of dose dependent lung inflammation and cellular changes in the lung and there are also diesel exhaust immunological effects. Based upon human and laboratory studies, there is considerable evidence that diesel exhaust is a likely carcinogen. Human epidemiological studies demonstrate an association between diesel exhaust exposure and increased lung cancer rates in occupational settings.

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Nitrogen Oxides (NOx)

Q: What is NOx?

A: Nitrogen oxides, or NOx, is the generic term for a group of highly reactive gases, all of which contain nitrogen and oxygen in varying amounts. Many of the nitrogen oxides are colorless and odorless. However, one common pollutant, nitrogen dioxide (NO2) along with particles in the air can often be seen as a reddish-brown layer over many urban areas.

Q: Where does NOx come from?

A: Nitrogen oxides form when fuel is burned at high temperatures, as in a combustion process. The primary sources of NOx are motor vehicles, electric utilities, and other industrial, commercial and residential sources that burn fuels.

Q: Why the concern about NOx?

A: NOx is a concern for the following reasons:

Q: What is being done to control the transport of pollution?

A: For some time, EPA has recognized that pollutant transport can impair an area's ability to meet air quality standards. As a result, in March 1995 a collaborative, Federal-state process to assess the ozone transport problem was begun. Through a two-year effort known as the Ozone Transport Assessment Group (OTAG), EPA worked in partnership with the 37 easternmost states and the District of Columbia, industry representatives, academia, and environmental groups to develop recommended strategies to address transport of ozone-forming pollutants across state boundaries.

On October 27, 1998 (63 FR 57356), EPA acted on OTAG's recommendations and issued the NOx transport rule, also known as the NOx SIP call, which requires 22 states and the District of Columbia to submit state implementation plans addressing the regional transport of ozone. These state implementation plans, or SIPs, will decrease the transport of ozone across state boundaries in the eastern half of the United States by reducing emissions of NOx (a precursor to ozone formation). The rule does not mandate how the reductions are to be achieved, but gives each affected state a NOx emission target. States have flexibility in determining how to reduce emissions.


Q: Why has EPA identified utilities as a major source for achieving NOx reductions?

A: The OTAG report identifies utilities as a major source for achieving significant NOx reductions; EPA's analysis agrees with the OTAG findings. Compared to other sectors that have already reduced emissions substantially, reduction from utilities and large boilers are generally less expensive.

Q: How does EPA's 1998 NOx Transport rule relate to the 126 petitions EPA received from 8 Eastern states?

A: Section 126 of the Clean Air Act gives States the authority to petition EPA to require specific upwind facilities, located in other states, to reduce their emissions. Under the 126 petitions, EPA sets nitrogen oxides emission limits on sources, whereas under the Section 110 NOx SIP call EPA establishes nitrogen oxides emission budgets and then States have the flexibility to determine where they achieve the reductions. The goal of the petitions is the same as the goal of the EPA rulemaking: significant reductions in regional transport of ozone smog. EPA is working with all the involved States to provide a consistent approach to these various provisions.

Q: How does this NOx transport rule that addresses the 1-hour standards relate to the new 8-hour ozone standard finalized in July 1997?

A: OTAG was established to address transport issues associated with meeting the 1-hour ozone standards. Shortly after OTAG concluded, EPA finalized a new 8-hour ozone standard. The regional reductions of nitrogen oxides achieved through this rulemaking are also key components for meeting the new air standards in a cost effective manner. EPA's analysis indicates that regional reductions of nitrogen oxides will bring the vast majority of new nonattainment areas -- those that meet the previous 1-hour ozone standard, but may not meet EPA's recently revised 8-hour national air quality standard for ozone -- into attainment of the revised standards without any additional local controls beyond those already required.

The OTAG process and this SIP call are focused on the long range transport of NOx emissions that contribute adverse health effects and poor air quality in downwind states. This transport causes problems downwind for areas trying to meet either the 1-hour or 8-hour standard.

Q: Why will NOx sources in attainment areas have to put controls in place?

A: The best available science shows that controlling ozone requires a combination of local control of volatile organic compounds (VOCs) and regional reductions of nitrogen oxides (NOx). Historically, state and local ozone smog control strategies have focused on reducing VOCs in local areas. However, NOx emissions--from sources like power plants sometimes located in attainment areas hundreds of miles away--can contribute to pollution problems in downwind areas. Some of these sources of NOx are very large and to date have been virtually uncontrolled. It is unfair to require downwind areas to continually reduce local emissions (often at very high cost) when the same benefits can be achieved, more cost effectively from upwind sources like power plants. There are ancillary benefits, as well. Local reductions help to mitigate the harmful effects of nitrogen oxides on sensitive waterways and estuaries like the Chesapeake Bay.

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Carbon Monoxide (CO)

Q: What Is It?

A: Carbon monoxide (CO) is an odorless, colorless gas that interferes with the delivery of oxygen in the blood to the rest of the body. It is produced by the incomplete combustion of fuels.

Q: What are the major sources Of CO?

A: Carbon monoxide is produced as a result of incomplete burning of carbon-containing fuels including gasoline, coal, wood, charcoal, natural gas, and fuel oil. It can be emitted by combustion sources such as unvented kerosene and gas space heaters, furnaces, woodstoves, gas stoves, fireplaces, and water heaters, automobile exhaust from attached garages, and tobacco smoke.

Q: What are the health effects?

A: Depending on the amount inhaled, this gas can impede coordination, worsen cardiovascular conditions, impair your vision and judgment, and produce fatigue, headache, weakness, confusion, disorientation, nausea, and dizziness. CO puts an extra burden on your lungs and heart. Very high levels can cause death.

Q: What are the symptoms?

A: The symptoms are sometimes confused with the flu or food poisoning. Fetuses, infants, elderly, and people with heart and respiratory illnesses are particularly at high risk for the adverse health effects of carbon monoxide. An estimated 1,000 people die each year as a result of CO poisoning and thousands of others end up in hospital emergency rooms.

Q: What can be done to prevent CO poisoning?

A: Ensure that appliances are properly adjusted and working to manufacturers' instructions and local building codes. Obtain annual inspections for heating system, chimneys and flues and have them cleaned by a qualified technician. Open flues when fireplaces are in use. Use proper fuel in kerosene space heaters. Do not use ovens and gas ranges to heat your home. Make sure your furnace has adequate intake of outside air. Carbon monoxide detectors should meet Underwriters Laboratories, Inc. Standards; have a long-term warranty; and be easily self-tested and reset to ensure proper functioning.

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Pollution Prevention

Q: What can be done to prevent pollution?

Did you know that your home and office contribute to the greenhouse effect? Energy used in our everyday activities -- turning on electrical appliances, driving cars, and heating and cooling our homes -- is responsible for air pollution that contributes to climate change. Technologies are available today that can cut this energy use significantly and, at the same time, improve our quality of life. Preventing pollution is as easy as looking for the ENERGY STAR Label. ENERGY STAR is already helping American homes, businesses, state and local governments and other organizations by reducing energy consumption, emissions of greenhouse gases and other harmful pollutants, and their associated energy costs.

Other things you can do:

Here's more information on the Climate Protection Partnership Division (CPPD).

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Q: What kind of air pollution is caused by radiation?
Radiation can be defined as the process of emitting energy in the form of particles or waves. Here's a summary of how it works. Matter is composed of microscopic particles called atoms. Radiation comes from atoms that are in the process of changing. This is true whether the atomic action is a naturally-occurring process, or a human-made process.

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Vehicles, Engines and Fuels

Q: What kinds of air pollution are produced by mobile sources?

A: Combustion of fuels can cause the release of hydrocarbons (HC), carbon monoxide (CO), oxides of nitrogen (NOx), particulate matter (PM), toxics, sulfur dioxide (SO2), and greenhouse gases such as carbon dioxide (CO2) and nitrous oxide (NO2). Mobile sources produce air pollution from exhaust emissions, as well as evaporative emissions and refueling losses from gasoline engines. The type and amount of pollution depends on many factors: the type of engine or vehicle (e.g., passenger car, heavy-duty truck, lawnmower, locomotive, etc.); the type of fuel used (e.g., gasoline, diesel, or alternative fuels); the type and condition of emission control devices (e.g., catalytic converters); and how the engine is used/run. For example, diesel engines used in trucks, buses, locomotives, and ships tend to emit more NOx and PM than gasoline engines. Engines with catalytic converters (e.g., passenger cars) emit much less HC, CO, NOx, and toxics than similar engines without catalysts (i.e., the catalytic converter is an important pollution control device to reduce exhaust emissions).

Q: What harm does diesel exhaust do?

A: The oxides of nitrogen (NOx) and hydrocarbons in diesel exhaust react in the atmosphere to form ground-level ozone, sometimes called smog. Ozone causes a range of health problems related to breathing, including chest pain, coughing, and shortness of breath. The sooty particulate matter (PM) in diesel exhaust can become deposited deep in the lungs and result in premature death, increased emergency room visits, and increased respiratory symptoms and disease. In addition, ozone, NOx, and PM adversely affect the environment in various ways, including through crop damage, acid rain, and reduction in visibility.

Q: What is Ultra-Low Sulfur Diesel Fuel?

A: Ultra-low sulfur diesel fuel (ULSD) is diesel fuel that contains no more than 15 parts per million of sulfur. Because sulfur clogs pollution control devices known as particulate matter filters or particulate traps, EPA is requiring that ULSD be available nationwide beginning in 2006. This cleaner diesel fuel will be available before the new trucks and buses that meet EPA's 2007 emisson standards debut on our nation's roadways.

Significant pollution reductions from existing diesel trucks and buses can be achieved by using ULSD in combination with emission particulate traps. This combination can result in up to a 90 percent reduction in emissions of particulate matter. However, some case studies suggest that the use of ULSD alone can reduce emissions of particulate matter between 10-20 percent. Although not available nationwide, ULSD is available today in parts of the Northeast.

Q: Why does farm equipment need emission controls?

A: Ozone and PM are regional problems in many parts of the U.S. Airborne pollutants generated in rural areas with good air quality can be blown many hundreds of miles and contribute to air quality problems elsewhere. Furthermore, there are many farms located close to urban areas, making it likely that most farm equipment models would need to be designed for low emissions anyway.

Q: What is I/M?

A: Auto inspection and maintenance (I/M) programs require the testing of motor vehicles in parts of the country with unhealthy air and the repair of those that do not meet standards.  I/M tests use special equipment to measure the pollution in your car's exhaust. These tests check that your car's key emission controls are installed as designed and then analyze the exhaust to check acceptable control of carbon monoxide and hydrocarbons (which form smog). Advanced tests also check nitrogen oxide emissions (which also form smog). Standards are set according to your car's model year. If your car exceeds those limits, it usually will pass its retest after minor adjustments, maintenance and repairs. More than 30 states have inspection and repair programs. By the year 2000, one-third of the nation's cars are scheduled to be included in I/M programs.

For more information on I/M programs see the following website: http://www.epa.gov/otaq/

Q: I just failed an emissions inspection. Do I have any warranty coverage?

A: Check out the following website: http://www.epa.gov/otaq/consumer/warr94fs.txt

Q: What emission related parts are covered under my new car warranty?

A: If you're vehicle is a 1995 model or newer, check out the following website: http://www.epa.gov/otaq/consumer/warr95fs.txt Note: this coverage is also explained in your vehicle owner's manual.

Q: What is being done about the smoke coming out of the trucks and buses? Why don't these vehicles have to be tested for emissions like cars?

A: The smoke you are seeing is particulate matter (PM). The smoke is coming from buses and trucks manufactured prior to 1993. Bus and heavy duty truck engines manufactured since 1993 have very tight particulate emissions standards and therefore do not emit visible smoke. It is very common for engines on pre-1993 buses to be rebuilt or replaced which means that these buses have longer lifetime expectancies and are not replaced by newer, cleaner buses. In 1993, EPA adopted a rule (called the Retrofit/Rebuild Program) which requires that when the engines are rebuilt or retrofitted that they must conform to tighter PM emission standards. The retrofit/rebuild program is intended to reduce the ambient levels of PM in urban areas and is limited to 1993 and earlier model year (MY) urban buses operating in metropolitan areas with 1980 populations of 750,000 or more, whose engines are rebuilt or replaced after January 1, 1995.

The emission testing program (also known as the I/M program) tests gasoline-fueled vehicles for hydrocarbon (HC), carbon monoxide (CO) and nitrogen oxide (NOx) emissions. Diesel-fueled vehicles emit low levels of HC and CO and high levels of NOx and PM. Congress has not given EPA the authority under the Clean Air Act to require heavy duty diesel trucks and buses to be emission tested like gasoline cars and trucks. However, several states have implemented in-use testing of diesel vehicles, particularly aimed that reducing PM emissions.

Check out the following website for more info on heavy duty bus and truck engines and the retrofit/rebuild program: http://www.epa.gov/otaq/hd-hwy.htm


Q: I have a question regarding the servicing of my vehicle's air conditioning. Who can I talk to about the CFC replacement program, and where can I register a complaint against a shop for improper repairs/disposal?

A: Contact EPA's Stratospheric Ozone hotline at 1-800-296-1996 or call EPA Region III Stratospheric Ozone Coordinator, Dick Eaton, at (304) 234-0265.

Q: Where can an automotive technician get information on a variety of environmental issues related to their profession?

A: Check out the website : http://www.ccar-greenlink.orgExit EPA Click for disclaimer

Q: How can I get a gas mileage guide, where can I get information on how EPA determines gas mileage estimates for new vehicles?

A: Go to the following EPA website: http://www.fueleconomy.gov

Q: How can I find out if EPA has approved an aftermarket fuel additive or device that is advertised to increase fuel economy and/or reduce vehicle emissions?

A: EPA does not approve, certify or endorse these products. EPA will evaluate them on a voluntary basis if requested by the manufacturer or at the direction of the EPA Administrator or the Federal Trade Commission. For more information on this evaluation and a listing of those devices/additives evaluated by EPA click on website: http://www.epa.gov/otaq/consumer/devicefs.pdf

Q: I would like to import a vehicle into the U.S. What do I need to do to comply with EPA regulations?

A: Check out the Customs webpage: http://www.cbp.gov/xp/cgov/trade/basic_trade/importing_car.xml Exit EPA Click for disclaimer Call EPA at (202) 564-9240 for help. EPA operates a faxback system whereby you can order EPA Import Forms. To get a fax of the form you require, call the Motor Vehicle Investigation/ Imports Section in Washington, DC at (202) 564-9660. Listen to the menu of options and enter your relevant info and fax number. You will automatically be faxed the requested forms the same day. Also see our web page entitled "Importing Vehicles into the U.S."

Q: I think my local gasoline retail station is selling "bad" gas. What should I do?

A: There should be a local or state agency number on the station's pumps. Call that number and report your complaint. If you can't find the local agency number, call the state environmental agency and ask for assistance.

Q: Where do I call to report illegal dumping of used oil/anti-freeze or to get more information on used oil recycling?

A: Call EPA's hotline 1-800-438-2474 and ask for the Technical Support Branch of the Waste and Chemicals Management Division.

Q: What is tampering?

A: Tampering is removing, disconnecting, damaging or in any way rendering ineffective any emission control device or element of design installed on a motor vehicle or motor vehicle engine. Tampering may include: removing or rendering inoperative such devices as the catalytic converter, air pump and EGR valve, disconnecting vacuum lines and electrical or mechanical portions of the pollution control system such as electrical solenoids or vacuum-activated valves; adjusting an element of a car's emission control design out of line with the manufacturer's specifications; knowingly installing a replacement part that is not equivalent in design and function to the part that was originally on the car; adding on a part that was not originally certified on the car such as installation of dual carburetors to replace a single carburetor or dual exhaust to replace a single exhaust system.

Q: What are some reasons why a person should not tamper with their car?

A: In most cases tampering will not improve a car's gas mileage and drive ability and may make them worse; tampering will increase your car's emissions and add to air pollution, tampering is an expensive waste because it nullifies emission controls that on a new model car may have cost $300 to $400 and tampering can void a manufacturer's emission control warranty.

Q: I believe that a local car repair shop/muffler shop has tampered with my vehicle. What should I do?

A: You can call EPA at (202) 564-1032 or (215) 814-2173 to report such a complaint. Ask to speak to someone who deals with vehicle tampering issues. EPA will target such business for enforcement actions.

Q: I purchased a used car from a used car dealer. I just discovered that the cars emission control devices have been tampered. What can I do?

A: Approach used car dealer and suggest paying half of amount to correct the tampering. Look into purchasing aftermarket control devices (i.e. emission control devices manufactured by a company other than the car manufacturer) since these parts are less expensive If the car dealer is not willing to cooperate then contact the Better Business Bureau. Unfortunately, EPA usually only takes action against these business' if a witness can provide testimony about tampering to implicate owner/mechanic. Call (215) 814-2173 and asked to be sent the following pamphlets: the EPA Exhaust System Guidelines, Engine Switching Fact Sheets and the Aftermarket Catalytic Converter brochure- Guide to Their Purchase, Installation, and Use.

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Q: What is Asthma?

A: According to the American Lung Association, asthma is the seventh-ranked chronic health condition in the United States and the leading chronic illness of children. It is a chronic inflammatory disease which makes airways (bronchial tubes) particularly sensitive to irritants.

Q: What makes someone develop asthma?

A: Some people are born with a predisposition toward developing asthma. However, what actually triggers the disease can vary from person to person. Common triggers include environmental tobacco smoke, air pollution, pollen, allergens from animals and insects, abrupt weather changes, biological contaminants such as mold, and viral infections.


Q: How can a person tell if they suffer from asthma?

A: Diagnosis is the first step in keeping the condition under control. Early warning signs include: fatigue; coughing, even when the person does not have a cold; wheezing; difficulty breathing; tightness in the chest; runny nose; itchy throat; and a change in the thickness, amount or color of the mucus. Anyone regularly exhibiting any of these symptoms should see a doctor or allergist as soon as possible. The earlier it is diagnosed the earlier the condition can be gotten under control.

Q: What can be done to prevent asthma and to avoid asthma episodes?

A: Do not allow smoking indoors unless there is a room reserved for smokers which has a separate ventilation system to exhaust smoke outside. Try to keep humidity levels in the home between 30 and 50 percent. High humidity can promote growth of biological agents that may trigger asthma episodes. Avoid using humidifiers. If it cannot be avoided, clean it according to the manufacturer's instructions; refilling it daily with fresh water. Minimize exposure to combustion particles and gases which can cause breathing difficulties for people with asthma. Keep the house clean to reduce allergens like microscopic dust mites, pollen, and animal dander. Use allergen-proof mattresses and box springs in vinyl covers. Try to keep pets out of bedrooms of family members with asthma. Consider using a high efficiency vacuum filter or a vacuum system that is vented to the outside.

Check out our asthma web page for more information.

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