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CHIEF Archive Search

The CHIEF Archive is a collection of references cited in the Compilation of Air Pollutant Emission Factors, AP-42, Volume I: Stationary Point & Area Sources and the supporting background documentation.

If you need older AP-42 emission factors for comparison or historical purposes, the earlier editions and supplements are available on the Older Editions of AP 42, Compilation of Air Pollutant Emission Factors webpage.

This information is provided for reference purposes only. This is an archive of older and often superseded documentation related to stationary source emissions factors.

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Search Tips

By default, the search locates documents containing words in the exact order they are typed. When you want documents containing any of several words, use commas to separate them.

For example, searching for:

1) formaldehyde emissions

will find documents that contain the phrase formaldehyde emissions somewhere in the document.


2) formaldehyde, emissions

will find documents that contain either formaldehyde or emissions.


3) formaldehyde and emissions

will find documents that contain both formaldehyde and emissions, but not in any particular order.
 
The search results are displayed in the EPA Search Results page.  Going to Advance Search from the Results page will search all of EPA.