Loading and Unloading Safety Rules
49 CFR Part 177 specifies the safety procedures for loading and unloading hazardous materials. Engine requirements during loading/unloading: when loading or unloading Class 1 Explosives, Class 3 Flammable Liquids, or Class 4 Flammable Solids/Liquids/Gases, the engine must be off. Exception: the engine may run if it is necessary to operate a liftgate or pump — but only with extra precautions. Smoking prohibition: no smoking within 25 feet of a vehicle loading or transporting Class 1 Explosives, Class 3 Flammable Liquids, Class 4 Flammable Solids, Class 5 Oxidizers, or Class 2.1 Flammable Gas. This 25-foot rule is a specific exam question target. Unattended vehicle rule: a vehicle transporting Division 1.1 or 1.2 Explosives must never be left unattended in a public place. If the driver must stop, the vehicle must be in a safe location away from bridges, tunnels, populated areas, and where fires cannot spread to the explosive load. Brakes and chocks: the parking brake must be applied and wheels chocked whenever the vehicle is parked for loading/unloading hazmat. Turn off engine during fueling: whenever fueling a vehicle carrying placardable hazmat, the engine must be off and the driver (or attendant) must remain at the fuel nozzle.