By CLARE GOLDSBERRY, associate editor

Oxyfuel gas welding can be a hazardous, yet good profession. And, while there are many safety specifications for oxyfuel welding, nothing is more important than paying attention to the basics, said Kris Bancroft, a contracted safety consultant in Dayton, Tenn. Bancroft has served on the Health & Safety Committee for the American Welding Society (AWS) for nearly 10 years and has helped develop safety standards. He said that welders have to remember that "when something bad happens in the welding industry, it's very bad."

That's why safety is the number one issue for the AWS, Bancroft said, adding that all the technological advances, safety equipment and inspection protocols that the AWS has developed over the years can't help if the welder doesn't implement them and make them a part of his everyday work habits.

Training is key in oxyfuel welding
"While there are a lot of safety apparatuses and technology that can prevent accidents, training in how to operate potentially dangerous equipment properly is a big part of safety. There are a lot of different components to the oxyfuel system [that welders] need training on in order to operate the system safely," said Bruce Buhler, training and product manager for Smith Equipment (www.smithequipment.com), a manufacturer of oxyfuel cutting, welding and heating equipment, and specialized gas regulators in Watertown, S.D.

Smith Equipment offers safety videos and training tests, and its Oxyfuel Welding Safety Pack that is designed to teach employees about safety includes 30 copies of its 37 Violations Safety Quiz and Safety Meeting Guides, and six cartoon Safety Posters to remind oxyfuel welders of the need to follow procedures.

Regardless of the training a person receives, Bancroft said that laziness often is a big reason that accidents happen in oxyfuel welding. Not only is proper equipment necessary, but equipment maintenance is critical to preventing accidents.

"Taking care of the equipment is not stressed enough by the supervisors, because the company is only making money when the guys are welding and cutting, not caring for their equipment."

Another issue, said Bancroft, is that welders tend to not notice the incremental wear and tear on their equipment because they're so close to it all the time. "It's sort of like our cars – we're riding along and all's okay, so we don't notice those little, incremental changes and things start to wear out," he said. "People need to have a routine for the maintenance of their equipment, and that's not established in a lot of trades. But, if they don't take the time to perform these small maintenance items that will keep their equipment in good condition, they might find out the hard way that something needed repairing or replacing."

Buhler said that there are a lot of safety devices, some which have been introduced in the last 15 to 20 years, such as flashback arresters and reverse flow check valves that are very beneficial to the health and safety of oxyfuel welders. "We've chosen to integrate flashback arresters into the torches we manufacture to prevent a fire inside the system," said Buhler.

That is one of the most dangerous aspects of oxyfuel welding. A flashback is a momentary or sustained retrogression of the flame upstream of the mixer usually in the torch or hoses, according to the AWS Safety and Health Fact Sheet No. 28. "This is a potentially hazardous situation, particularly if the flame reaches the hoses where an explosion will result causing a rupture or separation of the hose," the fact sheet says.

A flashback typically is caused by the reverse flow of gases into the hoses or other equipment, and has several causes. It is usually the result of improper shutdown and/or startup procedures; that allow cylinder pressures to become too low or by a check valve that is not working properly, the AWS Fact Sheet says.

Buhler said procedures for best practices should include checking the system at the start of the shift when the welder sets it up, and leak tests from time to time during a shift to ensure there are no leaks in the system.

"Also, there's a proper way to light a torch and proper way to shut it down, and that is critical to safety," he said. "The three biggest safety procedures are to open the oxygen cylinder slowly when it's first opened; purge your lines each time before lighting the torch, and make sure you've got enough gas to support the tip you're using and that it's adjusted correctly for the application. You don't want to starve the tip of gas, as this can cause overheating. If you don't have enough volume to support the tip size and/or if the flame is adjusted improperly, that leads to or potentially creates a flashback condition."

Bancroft said that while many items in the oxyfuel system do not need to be inspected daily, a periodic inspection protocol should be established to ensure that these items receive inspection on a regular basis. For example, he said, "O" rings in the welding torches should be inspected at least once a month or when replacing a new gas bottle, or if the welder suspects the torch has been overheated.

Regulators have a critical function, and Bancroft said that many welders leave the diaphragm screw "engaged against the diaphragm" while the system is shut down. While this might be convenient for the welder, this practice shortens the life of the regulator.

Safety Tips Here is a list of primary safety tips from Safety Consultant Kris Bancroft: 1) The welder should keep his breathing zone outside the plume of gases and smoke produced by hot works. Keep your head above the smoke and gases. 2) Keep the work area clear of flammables and combustibles, as stated in the ANSI welding standards. The ANSI standard provides a requirement that a 35-ft. radius be kept clear in hot work practices, including oxyfuel welding. 3) Maintain equipment properly. Regulators, torch tips and hoses have to be kept in good condition. 4) Have a daily inspection routine. A visual inspection of welding equipment should be done at the beginning of each workday. 5) Make sure the valves and fittings are completely free of grease and oil. The presence of petroleum-based and other compounds can cause a fire.

ANSI Standards ANSI Standard Z49.1: 1999, Part II Specific Processes, #10 Oxyfuel Gas Welding and Cutting Safety, contains a section on safety that includes the following statements: • 10.2.1 Call Oxygen by Name: Oxygen shall be called by its proper name, oxygen, and not by the word air. • 10.2.2 Call Fuel Gases by Name: Fuels, fuel gases and liquid fuels shall be called by their proper name, such as, acetylene, propane, natural gas, and not by the word gas. • 10.5.2. Details Operation such as: • 10.5.2.1 Leak Testing Connections. Connections shall be checked for leaks after assembly and before lighting the torch.Flames shall not be used [for leak tests]. • 10.5.2.2 Purging Hoses. Before lighting the torch for the first time each day, hoses shall be purged individually. Hoses shall not be purged into confined spaces or near ignition sources. Hoses shall be purged after a cylinder change. • 10.5.2.3 Lighting Torch. A friction lighter, stationary pilot flame, or other suitable source of ignition shall be used. Matches, cigarette lighters, or welding arcs, shall not be used for lighting torches. • 10.5.2.4 Confined Space. In confined spaces, the torch valves shall be closed and in addition, the fuel gas and oxygen supply to the torch shall be positively shut off at a point outside the confined area when ever the torch is not to be used, such as during lunch or overnight. Unattended torches and hoses shall be removed from the confined space.

Dos and Don'ts There are many dos and don'ts to promote safety in oxyfuel gas welding, and information can be gathered from a variety of sources including the AWS, where you can find information from the Health & Safety Committee and the ANSI standards for safety as well. Manufacturers, such as Smith Equipment, that make equipment offer advice, as do experienced welders who have worked in the trade for many years and have developed safety criteria for the trade.

For more information on safety, visit the AWS web site at www.aws.org and look under Safety. Also, an 8-page guide titled Safety Precautions in Oxyfuel Welding can be found at www.arcraftplasma.com/oxyfuelsafety.htm