Oxy-fuel gas welding and cutting apparatus can be used safely. However, failure to take basic
safety precautions can result in serious personal injury and material loss.
Following the DOs and DO NOTs listed here could reduce the chance of a serious accident.
DO carefully read the equipment manufacturer’s operating instructions before using the equipment. If you do not
have the operating instructions, get a copy from the equipment’s manufacturer or its local distributor or get
a copy of general instructions.
DO have a qualified person demonstrate the proper operating procedures before attempting to install or use the
equipment unless you are already familiar with the equipment.
DO follow the equipment manufacturer’s operating instructions at all times. Deviation from these instructions
could result in injury and/or property damage.
DO inspect oxygen regulators before installing them on cylinders. Inlet connections shall be clean. If there is
evidence of oil, grease, or other contaminants on the nut, nipple, or filter, have the regulator inspected and
cleaned by a qualified repair facility before use.
DO inspect the oxygen cylinder valve outlet connection before attaching the regulator to ensure that there is no oil,
grease, or other contaminants present. Return the cylinder to the supplier if any contamination is evident or
if the valve is damaged.
DO back off the pressure adjusting screw of the regulator to release spring force before opening the cylinder valve.
DO open the cylinder valves very slowly. Opening oxygen valves quickly could result in a violent reaction if
contaminants are present.
DO stand with the cylinder between yourself and the regulator (cylinder valve outlet facing away) when opening the
DO use protective clothing and appropriate eye protection when operating oxy-fuel gas apparatus. Severe injury can
result from sparks, splashing metal, and intense light.
DO purge hose lines individually before lighting the torch tip. This will ensure that no oxy-fuel gas mixture is
present in the hoses, which could cause an explosion or fire when the torch is ignited.
DO ensure that the work area is kept free of combustible materials. Sparks can ignite materials such as paper, rags,
wood, and plastic and cause serious fire damage. Sparks can fly 35 ft (10.7 m) or more.
DO ensure that the work area is adequately ventilated. Welding, cutting, and heating processes can enrich or deplete
the oxygen concentration of the air. An oxygen-deficient atmosphere can cause suffocation in seconds while an
oxygen-enriched atmosphere is a severe risk for accelerated fire or explosion.
DO have equipment inspected periodically and have repairs made by a qualified repair facility.
DO ensure that hose line check valves and flash arrestors are inspected and tested at the regular interval recommended
by the manufacturer so that they function as intended.
DO NOT handle oxygen regulators, oxygen cylinders, valves, or any other equipment with oily or greasy hands or gloves.
Oxygen reacts with oil and grease in a manner that will easily result in fire or explosion.
DO NOT attempt to repair or substitute parts on equipment, particularly regulators. Special tools, cleaning procedures,
and techniques are needed to safely repair oxy-fuel gas welding and cutting apparatus. Qualified personnel should
make repairs using the parts and procedures specified by the equipment manufacturer.
DO NOT change regulators from one gas service to another or replace a pressure gauge with one taken from any other
service. Contamination that results in a fire or explosion can occur.
DO NOT use oxygen in place of compressed air to supply pneumatic equipment, tools, hoses, or blow guns. A serious
fire or explosion can result.
DO NOT blow dirt off clothing with oxygen. The fabric can become saturated and burst into flames if touched off by
an ignition source such as a spark, flame, or cigarette.
DO NOT enter an unventilated confined space without first ensuring that the oxygen concentration is at a safe level.
Use an oxygen analyzer to measure the concentration.
DO NOT use acetylene at operating pressures above 15 psig (103 kPa). This is the maximum working pressure permitted
by federal regulations.
DO NOT empty an oxygen cylinder below 25 psig to 50 psig (172 kPa to 345 kPa). If the oxygen cylinder is allowed to
become completely empty, it will lose its positive pressure, and fuel gas or other contamination may enter the
cylinder creating a hazardous situation.
DO NOT transfill or refill oxygen or fuel gas cylinders. Return them to the gas supplier for proper testing and
filling. Special procedures and requirements are necessary to safely fill cylinders.
DO NOT leave pressure in a regulator when it is not in use. Close the cylinder valve, drain the hose in a safe
location, and back off the regulator pressure adjusting screw to release spring force.
DO NOT smoke when oxygen or fuel gases are present. Smoking can be an uncontrolled source of ignition causing fire