The Pocket Guide has been designed to provide chemical-specific data to supplement general industrial hygiene knowledge. To maximize the amount of data provided in this limited space, abbreviations and codes have been used extensively. These abbreviations and codes, which have been designed to permit rapid comprehension by the regular user, are discussed for each column in the following subsections.

Chemical Name and Structure/Formula,
AS and RTECS Numbers, and DOT ID
and Guide Numbers

Chemical Name and Structure/Formula - The chemical name found in the OSHA General Industry Air Contaminants Standard (29 CFR 1910.1000) is listed first. The chemical formula is also provided under the chemical name.

CAS and RTECS Numbers - The Chemical Abstracts Service (CAS) number, in the format xxx-xx-x, is unique for each chemical and allows efficient searching on computerized data bases. The NIOSH Registry of Toxic Effects of Chemical Substances (RTECS) number, in the format ABxxxxxxx, may be useful for obtaining additional toxicologic information on a specific substance.

DOT ID and GUIDE Number - The U.S. Department of Transportation (DOT) identification number and the corresponding guide number. Their format is xxxx xxx. The Identification number (xxxx) indicates that the chemical is regulated by DOT. The Guide number (xxx) refers to actions to be taken to stabilize an emergency situation; this information can be found in the 1996 North American Emergency Response Guidebook (Office of Hazardous Materials Training and Initiatives [DHM-50], Research and Special Programs Administration, U.S. Department of Transportation, Washington, D.C. 20590-0001; for sale by the U.S. Government Printing Office, Superintendent of Documents, Mail Stop: SSOP, Washington, D.C. 20402-9328). A page index for all DOT ID numbers listed is included at the back of the Pocket Guide to help the user locate a specific substance; please note however, that many DOT numbers are NOT unique for specific substances.