Risk Assessment

Risk Assessment (RA) Procedures for Rules 1401 and 212


Risk assessment procedures, including procedures for a simple risk screening, were developed by South Coast Air Quality Management District (South Coast AQMD) staff for the adoption of Rule 1401 - New Source Review for Toxic Air Contaminants, in June 1990.

The purpose of this document is to:

  • assist applicants and engineers to help evaluate Rule 1401 (PDF) compliance;

  • provide explanations and sample calculations; and

  • provide industry worksheets.

This document describes the procedures for preparing risk assessments under Rule 1401 (PDF) and Rule 212 (PDF)– Standards for Approving Permits. It is intended to be a "living" document. That is, as new toxic air contaminants (TACs) are added, risk values changed, or procedures revised, the document will be updated. Past procedures will be archived and TAC listings have been separated by the time period of significant Rule 1401 (PDF) changes.

This also serves to remind the user of this document that Rule 1402 (PDF)– Control of Toxic Air Contaminants from Existing Sources was amended on March 17, 2000 to establish an Action Risk Level of 25-in-one million for the entire facility.

Current Risk Assessment Procedures and Corresponding Attachments: 

Risk Assessment Procedures v8.1 (PDF, 329 KB), Version 8.1, dated September 1, 2017.   Procedures, Equations, and Assumptions Effective On or After October 1, 2017.

RiskTool (V1.105) R040919 - South Coast AQMD Procedure 8.1 (xls, 2 MB)

Attachment N (PDF, 896 KB), Version 8.1 Tables Effective for Applications Deemed Complete on or After October 1, 2017.

For previous versions of the Risk Assessment Procedures, please see the Risk Assessment Procedures archive.

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