Who must label hazardous materials? Question Who must label hazardous materials? Answers The mechanic The shipper The driver Explanation The shipper of hazardous materials is responsible for packaging, marking, and labeling the materials properly. It is a good idea for the driver to ensure the materials are properly labeled. This questions appears in the following tests: Arizona HazMat Kentucky HazMat Kentucky HazMat Louisiana HazMat Minnesota Tank Missouri HazMat Tennessee HazMat Tennessee Tank Vermont HazMat Virginia HazMat