Keep current with welding best practices
April 6, 2009
With thousands of welding related injuries reported each year, it’s important to recognize that welding safety is different from general safety practices and requires special attention in each shop. While some businesses regularly conduct welding operations, others have only occasional projects. But whether or not welding is a primary activity, safety professionals and occasional welders need to stay current with safety practices, regulations and sources of information.
Welding safety basics
Employers are responsible for educating and training their employees on OSHA regulations (as required by law). They also must familiarize workers with material safety data sheets (MSDS) and with the labels on products being used. A common misconception is that information on the MSDS pertains only to chemicals. In reality, the MSDS also addresses welding consumables like welding filler metals. Once this is understood, personnel should be properly trained on the welding equipment they will be using.
A deeper look at PPE
The occasional welder might not appreciate the implications of not using proper safety equipment, nor fully understand the possible effects of using the wrong PPE. In addition to safe practices, proper selection and use of the following PPE is absolutely essential to avoid injury:
- Face/head protection – Welding helmets protect from sparks and flying particles. In addition, there are several types of flipup face shields that can be mounted to typical hard hats.
- Eye protection – A welding helmet or hood equipped with the proper filter lens provides only secondary eye protection from welding ray flash burns. Primary eye protection, such as welding goggles or safety glasses with side shields, is required for protection from flying fragments and debris.
- Skin protection – Use of welding gloves is a given, but leather and flame-retardant welding aprons, sleeves, jackets, capes and coveralls protect from flying sparks and spatter, as well as from flash burn. Welders should avoid apparel with cuffs or open collars that might catch sparks, as well as any clothing made from synthetic materials that easily burn or melt.
- Noise protection – While earplugs can prevent hearing damage, earmuffs are necessary to shield welders’ ears from sparks and spatter.
- Respiratory protection – Welding fumes contain vaporized metal from both the material being welded and the welding rods and wire, coatings and fluxes. Fumes can also be generated from rust, mill scale or other metal coating, making it necessary to know the metal(s) being welded and to study the MSDS that accompanies all materials. If stainless steel, high-chrome alloys or chrome-coated metals are being welded, the fumes can contain Cr(VI) (hexavalent chromium). OSHA has established a new permissible exposure limit for Cr(VI), lowering it by a factor of 10. Workers should be aware of the appropriate exposure limits for all chemicals and fumes â€” these limits should be noted on the MSDS. Weld only in areas with adequate ventilation, and in the case of infrequent welding, use local ventilation such as fans or self-contained portable fume extractors with filtration capability. Permanent engineering controls are always preferred to assure proper ventilation, and an industrial hygienist may need to be consulted to determine if exposure is within the applicable limits. If necessary, employers must provide appropriate respirators.
Certain environments and situations present their own welding hazards. These include, but are not limited to:
- Confined spaces – Poor ventilation in confined spaces reduces safe breathing air and causes the buildup of hazardous gases, fumes and particles. Continuous ventilation and monitoring is necessary to ensure that levels of gases and fumes do not exceed permissible limits. A properly equipped watchperson who is trained for rescue should remain outside and maintain continuous communication with the worker inside. A means must be provided for quick removal of the welder in case of emergency.
- Fires – If welding cannot be performed in a properly secured area and if fire hazards cannot be removed, a welding shield or curtain is needed to confine the heat, sparks, spatter and slag. Precautions should be taken to protect combustibles on the other side of metal walls/barriers. When welding in nondedicated areas, employers should consider assigning a fire watchperson. Suitable fire extinguishing equipment should be readily available and employees should be trained in its use.
- Trips/falls – Welding cables and hoses should not be strung out along the floor or draped over equipment where they can present tripping hazards, especially for welders wearing darkened lenses.
There are some specific safety considerations to keep in mind depending on the type of welding being undertaken. Arc welding presents the following dangers:
- Flash burns – Eye protection is a must, but electric arc radiation can also burn skin with results similar to burns caused by exposure to intense direct sunlight. Flame-resistant protective apparel affords skin protection from flash burns as well as from typical sparks and spatter. An OSHA-specified welding curtain/screen may be needed to avoid exposing nearby employees.
- Electromagnetic fields – Exposure to electromagnetic fields should be minimized. The electrode lead should never be coiled around the welder’s body, and the electrode and work cables should be routed together.
- Electrical shock – Since electrical shock can kill, staying dry is the best defense. Welders should be sure to wear thick rubber or leather-soled boots, frequently change clothes wet from perspiration, use dry welding gloves and avoid standing in water to reduce the risk of electrical shock.
Gas welding has its own set of challenges. Gas cylinders are heavy and can contain pressures up to 2500 psi. A falling cylinder poses a serious risk to lower extremities and should be properly secured at all times. If cylinders can’t be secured to wall brackets, carts are available to move and secure them at the welding site. Gas cylinders should be protected from excessive heat, open flames, slag and sparks. To avoid possible damage that could result in unintended release of high pressure gas, pressure regulators should be removed from cylinders not in use and cylinder caps should be secured on the top of the cylinder. Cylinder carts should always be used to move cylinders.
Create a comprehensive plan
Incorporating these safety considerations into your operation will help keep the occasional welder from becoming another injury statistic. Welding safety doesn’t just happen. It requires more detailed safety considerations than even those that have been presented here. More information is available from the American Welding Society (AWS), OSHA, the National Institute for Occupational Safety & Health (NIOSH) and other resources.