Question Who must label hazardous materials? Answers The shipper The loader The driver The mechanic Explanation The shipper of hazardous materials is responsible for packaging, marking, and labeling the materials. They must supply any necessary placards. This questions appears in the following tests: Alabama Tank Colorado HazMat Maryland HazMat Maryland HazMat Massachusetts HazMat South Carolina HazMat South Dakota Tank Utah HazMat West Virginia HazMat