Question A placard identifying hazardous materials must be placed: Answers Inside the trailer. Inside the cab. On the outside of the vehicle. Explanation When required, hazardous materials placards must be placed on the front, rear, and both sides of a vehicle. Take a FREE Practice Test Now This questions appears in the following tests: Arizona HazMat , Louisiana HazMat , Nevada HazMat , New Mexico HazMat , Oklahoma HazMat , South Carolina HazMat , South Dakota HazMat , Tennessee Tank ,