EPA’s Office of Air Quality Planning and Standards (OAQPS) estimated census tract annual average outdoor concentrations of 181i hazardous air pollutants (HAPs), also known as air toxics, as part of EPA’s National Air Toxics Assessment (NATA) for the calendar year 2005.
You will need Adobe Reader to view some of the files on this page. See EPA’s About PDF page to learn more.- Methods: Hazardous Air Pollutants (PDF)(8 pp, 149 K)