Air & Waste Management Association (A&WMA ) - Environmental information including air pollution, hazardous waste, management, regulations, measuring, modeling, emissions, testing, monitoring, modeling, particulate matter, ozone, and brownfields

AIR Web - Air quality and visibility in U.S. national parks, refuges, and other protected areas. From National Park Service Air Resources Division and Fish and Wildlife Services.

AIRNOW - U.S. EPA - Air pollution data, ozone forecasting, information about public health and environmental effects of air pollution, and actions you can take to reduce pollution.

Automobile Emissions: An Overview - U.S. EPA fact sheet. [PDF format]

Bay Area Air Quality Management District - The BAAQMD (District) is the regional, government agency that regulates sources of air pollution within the nine San Francisco Bay Area Counties.

California Air Resources Board - CA air regulations, CA Almanac of Emissions and Air Quality, air emissions modeling, the gasoline additive MTBE, information on reducing air pollution from marine engines, and management of smoke from agricultural burning.

Canada's Toxic Release Inventory - Information about releases of pollutants into air, water and land. From Environment Canada.

Chicago Department of Environment - Gives information on Chicago's air quality and regional pollution prevention programs.

Clean Air Canada - Up to date information on air quality issues in Canada. Including environmental law and policy, motor vehicle emissions and industrial sources of pollution. Maintained by students at the Environment Law Centre, University of Victoria.

Clean Air Society of Australia and New Zealand - Focus is air quality and the mechanics of air pollution. Information about publications, training courses, conferences, and seminars.

Clean Air Task Force - A nonprofit organization dedicated to restoring clean air and healthy environments in the United States through scientific research, public education, and legal advocacy.

Denver Vehicle Emissions Testing Program - Describes the mandatory vehicle emissions testing program in the Denver-Boulder area of Colorado, including maps to emissions stations, testing requirements, help for failing vehicles and tips to keep from becoming a gross polluter.

DieselNet: Diesel Emissions Online - Information service on diesel exhaust emissions, emission control technologies, diesel engines, fuels, and related topics.

EDF Chemical Scorecard - Toxic Release Inventory data for the US (emissions of toxic chemicals to air and water). Search for data on toxic chemicals in your community. Also provides information on human health effects.

EHC Air Quality Program - National Safety Council's Environmental Health Center (EHC) conducts a variety of outreach and education activities on air quality issues. Topics include indoor air quality, mobile emissions, and radon.

Environmental Expert.com - Presents free accessible articles, publications, events, software, technological solutions and web resources for Air Pollution Control.

Environmental Software and Modelling Group, Technical University of Madrid - Conducts research in measurement and modelling of air quality, including air quality prediction.

Environmental-Expert.Com - Environmental site with large up-to-date section on air pollution.

Fuel Efficiency Automobile Test Data Center - The site contains vehicle emissions databases and reports remotely collected from in-use vehicles since 1987 from around the world. Data sets include cars, light-trucks, heavy-duty trucks, jet aircraft, locomotives and snowmobiles.