Question If transporting mass explosives: Answers The vehicle must always be placarded. The vehicle only needs to be placarded if carrying more than 200 pounds. The vehicle does not need to be placarded. Only rural roads should be used. Explanation For some hazardous materials, placards are only required to be used if 1,001 pounds or more are being carried by a vehicle. For others, including mass explosives, placards are required to be used when carrying any amount of the material. This questions appears in the following tests: Massachusetts HazMat Nebraska HazMat Nevada HazMat New Jersey HazMat