OXY-FUEL SAFETY GUIDELINES 1
OXY-FUEL SAFETY “IT’S ALL ABOUT EDUCATION” SAFETY FIRST Our primary goal is to prevent personal injury and illness to individuals nearby or using the equipment for oxy-fuel cutting, welding, brazing and heating. PURPOSE AND GOAL The scope of this document is to provide a basic understanding of the elements involved in the different oxy-fuel processes and to offer guidelines for the safe and proper operation of the equipment used.
THE COMBUSTION PROCESS At this point, a general explanation of the combustion process itself and the principal elements composing it is required. To best explain the combustion process, please reference the Fire Triangle illustrated in FIGURE 1. Figure 1 - FIRE TRIANGLE in the system at any time not intended by design. Oxygen and fuel gas are relatively safe by themselves when mixed in the right location.
OXY-FUEL SAFETY “IT’S ALL ABOUT EDUCATION” GASES OF THE OXY/FUEL PROCESS There are a number of hazards associated with the various oxy-fuel processes. A number of them directly relate to pure oxygen, oxygen in air and the type of fuel gases used. Fuel gases are there to provide the fuel element for the fire and BTU energy needed. Pure oxygen, when added, provides the oxy-fuel flame with its extraordinarily high temperature and volatility.
Figure 4 - OXYGEN CYLINDER mixtures due to reverse flow. Operators should follow the specific purging instructions offered by the original equipment manufacturer.
OXY-FUEL SAFETY “IT’S ALL ABOUT EDUCATION” FUEL GASES All fuel gases are obviously hazardous because they are flammable. They will burn in air alone, ignite readily, produce a lot of heat and their flame is self-sustaining even in plain air. Combined with the right amount of oxygen, fuel gases become extremely dangerous and potentially explosive. There are a number of common, yet different, fuel gases. Each gas has its own unique chemical and physical properties with differing hazards for each.
cylinders also feature unique thermally activated pressure relief devices. When exposed to high temperatures, the valves are designed to relieve excess pressure, in a controlled manner, preventing the cylinder from exploding. Acetylene is shock sensitive so incidents and other evidence of abuse, like cylinder wall dents, should be reported to the gas supplier as soon as possible.
OXY-FUEL SAFETY “IT’S ALL ABOUT EDUCATION” Figure 9 - LPG VALVE HAND WHEEL PACKAGING NUT OUT TO REGULATOR SINGLE SEAT VALVE RESEATABLE VALVE SAFETY FROM CYLINDER NATURAL GAS The third most common gas used for oxy-fuel processes is natural gas. Some authorities believe it to be the most widely used by volume. Natural gas is comprised of a mixture of gases, but methane is the most prominent of the mixtures.
DEVICES FOR ADDITIONAL OXY FUEL SAFETY Figure 12 - FBA FUNCTIONS CHECK VALVE Oxy-fuel equipment manufactured to currently acceptable national industry standards is generally as safe as it can be, assuming that the equipment is operated and maintained properly. Over time, however, normal wear and tear, operator abuse, and human complacency can make the best equipment unsafe even with the best of intentions.
OXY-FUEL SAFETY “IT’S ALL ABOUT EDUCATION” Figure 13 - PPE Figure 14 - TYPICAL OXY-FUEL CYLINDER SET-UP HEAD COVER INDUSTRY APPROVED EYE PROTECTION POCKETS WITH FLAPS LONG SLEEVES LEATHER GLOVES WITH GAUNTLETS FUEL GAS HIGH TOP BOOTS PANTS WITHOUT CUFFS ADDITIONAL PPE INFORMATION • Head protection – Head covers protect from flame, heat and metallic sparks. Recommend the use of hard hats for some work environments.
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The Harris Products Group A Lincoln Electric Company 2345 Murphy Blvd. Gainesville, GA 30504 Phone 1.800.733.4043 www.harrisproductsgroup.
