Special Precautions for Specific Gases

Butadiene is a flammable gas which must be inhibited when offered for transportation because of hazards arising from the potential for polymerization. In high concentrations, it is an anesthetic that can cause respiratory paralysis and death after prolonged breathing. Lower concentrations may produce slight irritation of eyes, nose, and throat. Butadiene is mildly aromatic, and blurring of vision and nausea are characteristic symptoms of exposure. The liquid will cause a freezing burn of the skin. 

Large butadiene fires are difficult to extinguish. Shutting off the source of the fuel and keeping all adajcent occupancies wetted with water spray are means to help control a fire. Small fires can be extinguished with CO2 or dry-chemical first aid extinguishers. 

Pressurized air should never be used for unloading. Butadiene should be unloaded through a closed system using a vapor return line and compressor, or by use of pressurized inert gas (such as nitrogen). When all the liquid is removed from the transport vehicle, valves should be closed and no air permitted to enter the tank. Butadiene transport vehicles should not be used for any other product unless the tank has been cleaned, freed of gas, and purged of air. See the monograph on butadiene in Part III for additional information. 

Vinyl chloride monomer is a flammable gas which is easily ignited and which produces hazardous combustion gases largely composed of hydrogen chloride and carbon monoxide. The odor of vinyl chloride vapors is pleasant, and when inhaled, vinyl chloride acts as an anesthetic. 

An explosion hazard can exist when drawing samples or venting to the atmosphere. Fire involving large quantities of liquid are difficult to extinguish since vinyl chloride is 

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