Acetylene

Overview

Acetylene is highly flammable under pressure and is spontaneously combustible in air at pressures above 15 psig.  Acetylene cylinders do not contain oxygen and may cause asphyxiation if released in a confined area.  Since acetylene is shock-sensitive and explodes above 30 psi, cylinders of acetylene contain acetylene dissolved in acetone.  Acetylene cylinders must not be placed on their sides, since the acetone and binders will have dislodged.  The result may be formation of an acetylene "pocket" that is subject to polymerization and the possibility that liquid acetone will be released into the regulator.

Emergency Procedures

In case of skin contact: Skin effects are not likely.  Contact with liquid acetylene may cause irritation upon repeated exposures.  Wash affected area(s) with soap and warm water.  If irritation develops, seek medical attention.

In case of eye contact:  Not a likely route of exposure since acetylene is a gas at room temperature.  Contact of liquid acetylene with the eyes may cause temporary irritation.  Flush with water for at least 15 minutes.  Seek medical attention as needed.

In case of inhalation: Acetylene is an asphyxiant and may cause anesthetic effects at high concentrations.  Victims should be assisted to an uncontaminated area with fresh air.  

In case of ingestion: Not a likely route of exposure since acetylene is a gas at room temperature.

Handling

Acetylene is shipped in a cylinder packed with a porous mass material and a liquid solvent, commonly acetone.  When the valve of a charged acetylene cylinder is opened, the acetylene comes out of solution and passes out in the gaseous form.  IT IS CRUCIAL THAT FUSE PLUGS IN THE TOPS AND BOTTOMS OF ALL ACETYLENE CYLINDERS BE THOROUGHLY INSPECTED WHENEVER HANDLED TO DETECT SOLVENT LOSS.   There should be no sources of ignition in the storage or use area.  If rough handling or other occurrences should cause any fusible plug to leak, move the cylinder to an open space well away from any possible source and place a sign on the cylinder warning of "Leaking Flammable Gas".  Contact Public Safety at 911.

Storage

Do not store acetylene cylinders on their side.  If an acetylene cylinder has tipped over or was stored on its side, carefully place the cylinder upright and do not use until the liquid has settled to the bottom.  The rule of thumb is not to use the cylinder for as many minutes as the cylinder was on its side, up to 24 hours.

Disposal

Acetylene cylinders should be returned to the compressed gas distributor when emptied or no longer used.

For More Information

See the MSDS for acetylene from BOC Gases.

Section 10: Chemical Specific Information