CAS service explained
Glenn P. Jirka
Hazardous Materials Specialist
University of Missouri Fire and Rescue Training Institute
While reading the quality article “Tier II Chemical Inventory Form a Preplanning Resource,” by Eric G. Bachman (March 1998), I felt that the fire service community may not fully grasp the significance of the CAS number from the description given in the article. As the author states, CAS stands for “Chemical Abstracts Service.” This service, rendered by the American Chemical Society, among other things, catalogs chemical compounds according to a set of rules. In fact, this system of rules is similar to the Dewey Decimal System used in libraries, as Bachman states. However, it does not classify chemical manufacturers and users ….
In fact, a CAS number is assigned to a single, specific chemical. It is unique to that material. Chemical professionals use this number while searching for information on a particular chemical. Additionally, chemical information can be retrieved by this number in several electronic databases used by emergency responders and chemical professionals. The CAS number is also used to index chemicals in hazardous materials reference sources such as the NIOSH Pocket Guide to Chemical Hazards and the NFPA Fire Protection Guide to Hazardous Materials. Currently, more than 17.5 million chemical substances have been indexed by CAS. Since the CAS number is unique to a chemical substance, it is an excellent piece of information to use when dealing with materials that have several chemical names, difficult names, long names, or abbreviations that coincide with other chemicals.