Identification numbers assigned to chemicals can be found: Question Identification numbers assigned to chemicals can be found: Answers In the DOT Emergency Response Guidebook. In the truck's operation manual. On the EPA’s website. At fuel stations. Explanation The United States Department of Transportation (DOT)’s Emergency Response Guidebook (ERG) lists all hazardous chemicals and their assigned identification numbers. This questions appears in the following tests: Alabama HazMat Arkansas HazMat Connecticut HazMat Georgia HazMat Indiana HazMat Mississippi Tank Oregon HazMat South Carolina HazMat West Virginia HazMat