Why were the listed chemicals chosen to be placed on the Appendix A list?
For more information on this topic, please reference the Final Rule, Appendix to Chemical Facility Anti-Terrorism Standards http://www.dhs.gov/xlibrary/assets/chemsec_appendixafinalrule.pdf on the DHS Critical Infrastructure: Chemical Security website. Referenced Text: Each chemical in Appendix A presents at least one security issue, and some chemicals present multiple security issues. Where there are multiple issues associated with a chemical, a facility must complete and submit a Top-Screen if it meets or exceeds the STQ for any of the applicable security issues.
