Safety in Welding and Metalworking
Barbara T. Nessinger, Chief Editor
According to the American Welding Society, an estimated 50% U.S. gross national product is affected by welding. Anything made of metal, no matter how big or small, can be welded. Welding is the most common method used to join metal parts in large structures and equipment, due to its strength. Soldering and brazing are similar processes to welding, but they are used on electronic and other small equipment and use lower temperatures to melt the filler metal.
Most welding today falls into one of two categories: arc welding (the use of an electrical arc to melt the work materials) and torch welding (the use of an oxyacetylene torch to melt the working material and welding rod). There are more than 100 welding processes; most involve a skilled worker using a high-heat torch, filler material that is usually in wire or stick form, and pressure to permanently bond metal pieces.
Welding, cutting, brazing and grinding all create significant fire and explosion risks. This type of work generates hot sparks and slag. Those can then come into contact with nearby combustibles and flammable gases.
Most welding safety practices and equipment are universally applicable. Welding exposes everyone to similar hazards, from a welding-intensive manufacturing company; a billion-dollar engineering and construction firm; a small independent fabricator; or someone responsible for safety-at-large in the workplace. Wearing the proper PPE equipment is extremely important to keep welders and watchers safe from multiple hazards.
Implementing good welding/hot-work safety practices can help do more than just save lives. When welding safety becomes an ingrained part of the corporate culture, there can be fewer reduced lost-time incidences and improved productivity. [See sidebar “Preventing Hot-Work Accidents.”]
Safety Matters: Proper Clothing
It was stated above, but it bears repeating: Wearing the proper gear for any welding activity is of paramount importance. Even quick work, such as tack welding, requires the proper safety gear, including helmet, gloves and clothing. Note: shorts and short-sleeved shirts should never be worn in a welding cell or doing any hot-work tasks.
Workers should wear only flame-resistant clothing, such as denim pants and a shirt made from tightly woven material or a welding jacket. Makers of safety gear now produce lightweight clothing from flame-resistant cloth, pigskin leather or combinations of the two that offer better protection and increased ease of movement than welding jackets/clothing of the past. Such work gear is no longer cumbersome to wear nor too heavy, hot or restricting.
Proper footwear is also important. High-top leather shoes or boots provide the best foot protection. Pants legs should go over the shoes. Shoes should never be made of cloth.
Welding gloves are available with ergonomically curved fingers and come in different designs for specific welding processes. MIG welding is the most popular weld for a broad range of applications. The heat levels are less than in Stick welding, and the user operates a welding gun with a trigger requiring more dexterity. MIG gloves tend to be lighter weight than Stick gloves and, most importantly, have enhanced dexterity.
Heavy-to-medium duty MIG/Stick gloves and TIG gloves that provide added dexterity and touch are just some of the options available. However, gloves are not sufficient to pick up just-welded material: Pliers should always be used to avoid burns.
Welding helmets are an obvious must-have piece of PPE equipment for any welding task, starting with light exposure. It takes only a moment of exposure to a welding arc’s rays for unprotected eyes to experience “arc flash,” which is a painful condition that may not appear until hours after the worker is exposed. Welding helmets also be should be fitted with a proper filter shade to protect the operator’s face and eyes.
Auto-darkening welding helmets are also available; they can reduce operator fatigue. The sensors on an auto-darkening helmet darken the lens in a fraction of a second. All auto-darkening helmets must meet ANSI standards, the most recent being ANSI Z87.1-2003. Industrial-grade helmets react at speeds of 1/10,000 to 1/20,000 of a second and have adjustable shades settings of #9 to #13 for welding. Industrial-grade helmets also have adjustable sensitivity and delay controls to adjust how long the lens stays dark after the arc stops. Auto-darkening helmets that darken with a reaction time of 1/2,000 to 1/3,600 of a second should generally be avoided for industrial applications. Also, cold weather delays the reaction time of auto-darkening helmets. Higher-end helmets are rated for use to 14° F. However, lower-end helmets have slower reaction times and might not darken quickly enough in cold weather.
Clearer vision improves the welder’s safety, comfort and efficiency. The panoramaxx helmet, by Optrel, allows for brightness and clarity of the welder’s view from setup, to welding and grinding, all the way through inspection. The panoramaxx also features Optrel’s patented Autopilot function, which features a unique, five-sensor array that measures the brightness of the welding arc and automatically adjusts to the correct shade level (5-12). If the welding parameters change, the Autopilot detects the changes and automatically corrects the shade level. Thus, the welder can better focus on his/her work, without interruption or having to adjust the shade setting. The helmet’s unique nose cut-out allows positioning of the auto-darkening display closer to the eyes; this enlarges the field of vision without adding extra weight.
Some of the newer helmets have different modes, allowing the same helmet to be used for welding, cutting or grinding. The most recent development is a mode that senses the arc electromagnetically, offering full protection when the sensors are obstructed, such as when pipe welding or welding out-of-position.
Eyes Have It
Approved safety glasses with side shields and ear protection should also be worn under a welding helmet. The lens shade should be appropriate for the welding application; OSHA offers a guide for choosing the correct lens based on certain welding criteria. If weld parameters and materials don’t vary, a fixed-shade lens could be the best choice.
Welding glasses or goggles are used by welders to provide protection to their eyes from heat, intense ultraviolet or infrared light, and flying debris during welding and cutting operations. If these are not used, it may lead to a severe burn of the cornea known as Photokeratitis, or welder’s flash. Welding glasses provide a degree of eye protection against some types of welding and cutting. These are however, not suitable for arc welding operations.
Welding is a common workplace task that requires a great deal of knowledge, training and patience to perform properly and safely. Most welders fully understand how to perform their jobs properly–it is the employers’ responsibility to make sure they also understand the inherent hazards and how to implement proper welding safety protocol—beginning with the proper PPE for each employee. WMHS
NIOSH Checklist for Arc-Welding Self-Inspection
The National Institute for Occupational Safety and Health (NIOSH) has many self-inspection check-lists, including for welding operations. This Self-Inspection Checklist covers regulations issued by the U.S. Department of Labor, Occupational Safety and Health Administration (OSHA) under the general industry standards 29 CFR 1910.254 and 1910.306, and the construction standards 1926.351 and 1926.353. It applies to the use of arc-welding and cutting equipment. [Go to https://www.cdc.gov/niosh/docs/2004-101/chklists/r1n64w~1.htm for more information.]
OSHA and ANSI Eye-Protection Guidelines
Many excellent sources exist for understanding and referencing eye protection guidelines. Some of those used for this article include: 29 CFR 1910.132, General Requirements; 29 CFR 1910.133, Eye and Face Protection; American National Standard Institute (ANSI)/ANSI/ISEA Z87.1-2015. Also, see the April 2018 issue of Workplace Material Handling & Safety, page 28, for a complete list of “Eye and Face Protection Device Definitions in ANSI/ISEA Z87.1-2015.”