A tank truck rolls over on the freeway during rush hour, sending gallons of isopropanol gushing out onto the tarmac. First to arrive on the scene will most likely be the local policemen or firefighters, who may not know isopropanol from isobutylene. Yet to respond effectively, they need to know the classification of the chemical involved in the incident: Is it flammable, corrosive or an explosion hazard? Are the vapors toxic? Should the liquid be diluted with fire hoses or will it form toxic gases upon contact with water?

To help emergency responders identify the materials they might encounter at the scene of a transportation accident and the threats the chemicals pose to emergency crews (and the general public), the U.S. Department of Transportation (DOT) has released The Emergency Response Guidebook 2004. Prepared as a joint effort by the transportation departments of the United States, Canada and Mexico, the book provides a guide to various hazard identification codes, explains the hazard classification system and gives numbers to call for assistance in each country.

The agency will make 1.73 million copies of the new guide available to police, fire and other emergency response teams. "Getting the right information into the hands of local police and firefighters will greatly improve our nation's front-line, first-response capability," says Samuel G. Bonasso, deputy administrator of the DOT's Research and Special Programs Administration (RSPA).

Copies of the guidebook are available through the U.S. Government Printing Office Bookstore as well as through commercial vendors. Public emergency response personnel can also find their state coordinator contact information by visiting the Hazardous Materials Safety Web site at http://hazmat.dot.gov, or by calling (202) 366-4900.