PAC Chemical Database, Updated 11 October 2023

Use the Main Menu above to access the U.S. Department of Energy's (DOE's) current data set of Protective Action Criteria (PAC) values in a variety of ways: as a searchable database, as an Excel file, and as a series of tables in PDF format.

This database provides information for 3,146 chemicals.

This database will house both old and new PAC/TEEL values, with the old values replaced as the chemical is reaffirmed. The reaffirmed chemicals will include the methodology used to arrive at the values and incorporate the most current references available. The revision is scheduled to be completed in June 2027, with reaffirmed PAC/TEELS added on a bi-monthly basis. After completion, the chemical database will fall into a maintenance schedule with a finite number of TEELS re-evaluated annually.

Emergency exposure limits are essential components of planning for the uncontrolled release of hazardous chemicals. These limits, combined with estimates of exposure, provide the information necessary to identify and evaluate accidents for the purpose of taking appropriate protective actions. During an emergency response to an uncontrolled release, these limits may be used to evaluate the severity of the event, to identify potential outcomes, and to decide what protective actions should be taken. In anticipation of an uncontrolled release, these limits may also be used to estimate the consequences of an uncontrolled release and to plan emergency responses.

DOE O 151.1, Comprehensive Emergency Management System, requires the use of Acute Exposure Guideline Levels (AEGLs) and Emergency Response Planning Guidelines (ERPGs) as the emergency exposure limits of choice, in order of preference. Because AEGLs and ERPGs exist only for a limited number of chemicals, DOE also commissions the development of Temporary Emergency Exposure Limits (TEELs) so that DOE facilities may conduct Emergency Planning Hazard Assessments (EPHAs) and consequence assessments for chemicals lacking AEGLs or ERPGs. TEELs are temporary limits for chemicals until AEGLs or ERPGs are developed. Together, AEGLs, ERPGs, and TEELs are referred to as chemical Protective Action Criteria - PACs.

TEEL values are always subject to change, being replaced by AEGLs or ERPGs when new values are published or updated when different exposure limits or new toxicity data are published.

PACs for emergency planning of chemical release events are based on the chemical exposure limit values provided in:

Final and interim Acute Exposure Guideline Levels (AEGLs). AEGLs (see AEGL Standing Operating Procedures) are developed by the U.S. Environmental Protection Agency (EPA). AEGLs are defined for five time periods: 10 minutes, 30 minutes, 60 minutes, 4 hours, and 8 hours. The 60-minute AEGL values have been selected for use in the PAC database.

Emergency Response Planning Guidelines (ERPGs). ERPGs are produced by the American Industrial Hygiene Association (AIHA) Emergency Response Planning Committee (see AIHA ERP Committee Procedures and Responsibilities).

Temporary Emergency Exposure Limit (TEEL) data sets.TEELs are developed by the DOE Office of Emergency Management Policy (NA-41) following the guidelines described in DOE-HDBK-1046-2016, Temporary Emergency Exposure Limits: Methods and Practice.

Requests for chemical additions to the PAC dataset, questions related to the current PAC values, or any other comments are welcome. Please send your requests, questions, or comments to the NNSA Office of Policy, Preparedness, and Readiness Assurance (NA-41) at