Loading and unloading explosives

This is in response to your recent letter to the Federal Motor Carrier Safety Administration asking if any Federal regulations apply to loading and unloading Division 1.1 to 1.6 (explosive) materials in a refrigerated motor vehicle with a wooden floor. Your letter was forwarded to the Office of Hazardous Materials Standards, Pipeline and Hazardous Materials Safety Administration, for reply. This agency is responsible for promulgating the Hazardous Materials Regulations (HMR; 49 CFR Parts 171-180), which regulate the commercial transportation of hazardous materials in the United States.

The loading and unloading requirements for explosives in a motor vehicle are prescribed in § 177.834 and 177.835 of the HMR. They require extreme care to be taken in loading, unloading, securing, and handling packages containing explosives so they are not exposed to any impact, projection, source of ignition, or damage that could cause these materials to react. Section § 177.835(f) also requires motor vehicles transporting a Division 1.1, 1.2, or 1.3 material to have floors that are tight (e.g., constructed closely so there are few or no intervening spaces). This section also requires the vehicle's interior cargo space be in good condition so there will be no likelihood the packages will be damaged by exposed bolts, nuts, broken side panels, floor boards or similar projections. Any portion of the interior that is in contact with the load must be lined with either non-metallic material or non-ferrous metals. Exceptions from lining the interior are provided for truck load shipments loaded by the U.S. Department's of the Army, Navy, or Air Force provided the Class 1 (explosive) materials are not likely to leak dust, powder, or vapor that may cause an explosion. Also, certain Class 1 shipments transported by motor vehicle that are intended for transportation by rail or vessel must comply with similar flooring requirements prescribed in § 174.104(b)(6), (b)(7), and (b)(8), and 176.170(c), respectively.

The HMR are silent on how to transport explosives under refrigeration or controlled temperature conditions, but do specify under § l77.834(l)(1) that a cargo heater on a motor vehicle must be rendered inoperable when the vehicle is transporting a Class 1 material. We are aware that some manufacturers and their customers prefer to control within a specific range the temperature of certain explosives from manufacture to delivery. If a motor vehicle's temperature control equipment includes a heater, please note that it must be rendered inoperable in accordance with § 177.834(l)(1).