Dept. of Homeland Security's Appendix A is Finalized

November 20, 2007 | EHSO Council

On November 20, 2007, The Department of Homeland Security (DHS) published “Appendix A to the Chemical Facility Anti-Terrorism Standards; Final Rule” in the Federal Register (Vol.72, No.233, 11/20/07, 65396-65435) which goes into effect immediately. For the final rule, please visit:

The list contains more than 300 chemicals ranging in quantities from 100 grams to 15,000 pounds. According to the rule, a facility that possesses a chemical of interest at or above the screening threshold quantity (STQ), must complete and submit a consequence assessment known as a Top Screen, a part of the Chemical Security Assessment Tool (CSAT) process. This assessment must be completed within 60 calendar days of the publication of the regulation in the Federal Register (60 calendar days from November 20, 2007). Furthermore, if a facility does not currently have the listed materials in the screening threshold quantity, but hits the threshold in the future, then the facility must also complete the Top Screen assessment within 60 calendar days of coming into possession of the listed chemical at or above the STQ.