Methyl chloride tank cars

Under no circumstances should water or other materials be introduced into tank cars which contain, or have contained, methyl chloride. Soapy water should be used to test for leaks, but glycerine should be used in freezing weather or around very cold pipes or equipment. An open flame must never be used to test for leaks on any containers holding methyl chloride. 

When single-unit tank cars are unloaded and all the liquid has been transferred, the greater part (but not all) of the methyl chloride vapors may be recovered by creating a slight pressure differential. Observe caution in this operation because a slight residual pressure must always remain on the tank car so that no air is drawn into it to form explosive mixtures when the pipes are disconnected. 

When unloading tank cars, and a leak occurs that cannot be readily repaired by simple adjustment or tightening of the fittings, call the methyl chloride manufacturer at once for instruction, and evacuate the area around the car immediately. Permit only properly protected and instructed personnel to enter the contaminated area. 

Fire and explosion hazards. Avoid all sources of ignition when unloading single-unit tank cars and TMU containers holding methyl chloride. 

Methyl chloride is authorized for shipment in cylinders, insulated single-unit tank cars, and TMU tanks and tank cars. It is also shipped in tank barges. Methyl chloride is also authorized for shipment in portable tanks and cargo tanks. 

Methyl chloride is authorized for shipment in insulated, single-unit tank cars that comply with... 

Methyl chloride is authorized for shipment in insulated, single-unit tank cars which comply with TC/DOT specifications 105J300W, 112T340W, or 112J340W provided that interior pipes of loading and unloading valves are equipped with excess flow valves of approved design. See 49 CFR 173.314. [5]... 

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