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Technology Transfer Network Clearinghouse for Inventories & Emissions Factors

Search and Retrieval of EPA Emissions Factors

WebFIRE contains the EPA’s emissions factors for criteria and hazardous air pollutants (HAP) for industrial and non-industrial processes. To retrieve EPA emissions factors, you can use either a Simple or Detailed Search. After you have selected an emissions factor from your search, WebFIRE also provides a link that retrieves the individual performance test values that were used to develop the EPA factor and all other individual performance test data values contained in WebFIRE that meet your search criteria.

Simple Search

The simple search allows you to search for emissions factor information in cases where you have limited knowledge of the emissions process of interest (e.g., the emissions process is a wood-fired boiler). You can retrieve emissions factor records by entering one or more simple terms such as source category name (e.g., dry cleaning, wood combustion, boilers), process description (e.g., spreader stoker, catalytic cracking), EPA’s Source Classification Code (SCC), or any other viable search term likely to be found in an emissions factor record.

For example, if you enter in the phrase “spreader stoker,” WebFIRE will display every EPA emissions factor that includes the complete phrase “spreader stoker” anywhere in the entire record. To make your search more specific, you can use the “AND” operator. For example, “spreader stoker AND PM10” will limit the results to the pollutant PM10. The “AND” operator must be capitalized. Do not use punctuation in the search window.

Enter your search term(s) in the window below and then click the "Submit Search" button. The default WebFIRE search does not include emissions factors that have been revoked by EPA (e.g., when a revised emissions factor replaces an older version). To include revoked factors in your search, uncheck the checkbox next to the search window.

Exclude Revoked Factors

For more information about the Simple Search, click on this link see the Help Information. If you do not get the results you desired using the Simple Search, try using the Detailed Search below.

Detailed Search

The detailed search allows you to focus the factor retrieval process by entering multiple terms for the search criteria including:

Clicking the button below will take you to the Detailed Search page where WebFIRE provides drop-down menus from which you can select the search criteria of interest. After a search is conducted, you have the option to refine your search, as necessary.


Office of Air Quality Planning & Standards | Technology Transfer Network
Clearinghouse for Inventories & Emissions Factors | WebFIRE

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