Previous AP-42 Versions, Supplements and Updates

Previous AP-42 Versions 

The AP-42, Compilation of Air Pollutant Emission Factors, was first published by the U.S. Public Health Service in 1968. The first through fourth editions, including supplements, and the original fifth edition, are available below. In September 1985, the fourth edition was split into two volumes. Volume I includes stationary point and area source emission factors, and Volume II includes mobile source emission factors.

This information is available for historical purposes only. For the most recent emission factors, supported by the EPA, please see the current AP-42 web site.

The files are scanned images and have been converted to Acrobat PDF.

First editions

• Compilation of Air Pollutant Emission Factors (1968) (pdf) (2.02 MB) , Environmental Health Series, US Public Health Service
• Compilation of Air Pollutant Emission Factors (1971) (pdf) (6.55 MB) , Preliminary Document
• Compilation of Air Pollutant Emission Factors (1972) (pdf) (8.33 MB) , Revised

Second edition

• Second edition (1973) (pdf) (9.33 MB)
• Second edition, supplement 1 (July 1973) (pdf) (1.12 MB)
• Second edition, supplement 2 (September 1973) (pdf) (747.41 KB)
• Second edition, supplement 3 (May 1974) (pdf) (2.55 MB)
• Second edition, supplement 4 (January 1975) (pdf) (2.82 MB)
• Second edition with supplements 1 - 4 (1975) (pdf) (13.29 MB)
• Second edition, supplement 5 (December 1975) (pdf) (6.77 MB)
• Second edition, supplement 6 (April 1976) (pdf) (2.4 MB)
• Second edition, supplement 7 (April 1977) (pdf) (4.58 MB)

Third edition

• Third edition including supplements 1- 7 from second edition (1977) (pdf) (20.38 MB)
• Third edition, supplement 8 (1978) (pdf) (4.62 MB)
• Third edition, supplement 9 (1979) (pdf) (6.88 MB)
• Third edition, supplement 10 (February 1980) (pdf) (5.54 MB)
• Third edition, supplement 11 (October 1980) (pdf) (3.43 MB)
• Third edition, supplement 12 (1981) (pdf) (5.59 MB)
• Third edition, supplement 13 (1982) (pdf) (4.38 MB)
• Third edition, supplement 14 (1983) (pdf) (6.5 MB)
• Third edition, supplement 15 (1984) (pdf) (3.41 MB)
• Third edition, Update package (1985) (pdf) (4 MB)

Fourth edition, Volume I: Stationary Point and Area Sources

• Fourth Edition, (1985) (pdf) (27.73 MB)
• Fourth Edition, supplement A (1986) (pdf) (13.64 MB)
• Fourth Edition, supplement B (1988) (pdf) (6.27 MB)
• Fourth Edition, supplement C (1990) (pdf) (5.73 MB)
• Fourth Edition, supplement D (1991) (pdf) (5.27 MB)
• Fourth Edition, supplement E (1992) (pdf) (8.69 MB)
• Fourth Edition, supplement F (1993) (pdf) (22.2 MB)
• Fourth Edition, with supplements A through F incorporated (1985 to 1993) (pdf) (58.8 MB)

Fifth edition, Volume I: Stationary Point and Area Sources

Most sections in the 5th edition have been updated. The most recent supplements are available on the the AP-42 webpage.

• Fifth Edition (1995) (pdf) (70.32 MB)

Updates and Supplements 

Supplements A through F (1996 - 2000) (pdf) (148.27 KB)

Supplements to the Compilation of Air Pollutant Emission Factors AP-42, Fifth Edition, Volume I: Stationary Point and Area Sources (pdf) (140.85 KB)