Shippers must keep a copy of shipping papers for: Question Shippers must keep a copy of shipping papers for: Answers Six weeks. Six months. One year. Two years. Explanation Shippers must retain a physical copy or an electronic image of hazardous materials shipping papers for a minimum of two years after the materials are accepted by the initial carrier. For hazardous waste, this increases to three years. This questions appears in the following tests: Alabama HazMat Arkansas HazMat Georgia HazMat Georgia HazMat Georgia Tank Illinois HazMat Indiana HazMat Kansas HazMat Montana HazMat Montana HazMat Nebraska HazMat Nevada HazMat New Hampshire HazMat North Carolina HazMat Wisconsin Tank