Acetylene flammable range

Flammable gases are defined by the U.S. Department of Transportation as those that when mixed with air are flammable in concentrations of 13 percent or less by volume in air or, if the gas has a flammable range wider than 12 percent in air, regardless of its lower flammable limit. Examples of flammable gases include acetylene, butadiene, carbon monoxide, ethane, ethylene, hydrogen, hydrogen sulfide, the liquefied petroleum... 

The usual precautions must be observed around the high tension electrical equipment supplying power. The carbon monoxide formed, if collected in closed furnaces, is usually handled through blowers, scmbbers, and thence to a pipe transmission system. As calcium carbide exposed to water readily generates acetylene, the numerous cooling sections required must be constandy monitored for leaks. When acetylene is generated, proper precautions must be taken because of explosibility of air—acetylene mixtures over a wide range of concentrations (from 2.5 to 82% acetylene by volume) and the flammability of 82—100% mixtures under certain conditions. 

For most flammable hydrocarbons, the LFL is around 2—5%. For gasohne vapors, the range is from a little over 1% to almost 8%. For simple alkanes, such as methane and ethane, the UFL value is in the 10—15% range. Some chemicals, such as hydrogen, ethylene oxide, and acetylene, have much higher values for UFL. 

Gases - flammable gases include LPG (liquefied petroleum gas in cylinders, usually butane or propane), acetylene (used for welding) and hydrogen. An explosion can occur if the air/ gas mixture is within the explosive range. 

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