Electromagnetic energy given off by an arc or flame can injure workers' eyes and is commonly referred to as radiant energy or light radiation. For protection from radiant energy, workers must use personal protective equipment, such as safety glasses, goggles, welding helmets, or welding face shields. This equipment must have filter lenses with a shade number that provides the appropriate level of protection. A shade number indicates the intensity of light radiation that is allowed to pass through a filter lens to one's eyes. Therefore, the higher the shade number, the darker the filter and the less light radiation that will pass through the lens.
This requirement applies to the employees performing the work and to personnel observing the operation; for example, a fire watch or an assistant. The tables below list the minimum protective lens shade numbers for commonly used welding and cutting processes.
When a worker wears eyewear equipped with filter lenses under a welding helmet, the shade number of the lens in the helmet may be reduced. The combined shade numbers of the lenses in the eyewear and helmet should equal the value shown in the tables below (see 29 CFR 1915.153(a)(4) and ANSI Z49.1:2005 Safety in Welding, Cutting, and Allied Processes). In addition, all protective eye and face devices must comply with ANSI Z87.1, Practice for Occupational and Educational Eye and Face Protection (see 29 CFR 1915.153(b)) for the selection, use and maintenance of these protective devices.
When there is a potential for objects to fly in workers' eyes and face, the protective device(s) selected must provide side protection. Side protection reduces the risks of hazards such as slag chips, grinding fragments and grinding bristles contacting a worker's eyes and face. Where such hazards exist, workers using a welding helmet with filter lenses would also need to wear glasses with side shields or goggles.
Table 1: Filter Lenses for Protection during Shielded Metal Arc Welding
|Operation||Electrode Size – inch (mm)||Arc Current (Amperes)||OSHA Minimum Protective Shade Number||ANSI & AWS Shade Number Recommendations*|
|Shielded Metal Arc Welding (SMAW)||Less than 3/32 (2.4)||Fewer than 60||7||-|
|More than 5/32-1/4 (4.0-6.4)||More than 160-250||10||12|
|More than 1/4 (6.4)||More than 250-550||11||14|
Table 2: Filter Lenses for Gas Welding and Oxygen Cutting Operations
|Operation||Plate Thickness Inches||Plate Thickness mm||OSHA Minimum Protective Shade Number||ANSI & AWS Shade Number Recommendations*|
|Gas Welding||Under 1/8||Under 3.2||4||5|
|1/4 to 1/2||3.2 to 12.7||5||6|
|Over 1/2||Over 12.7||6||8|
|Oxygen Cutting||Under 1||Under 25||3||4|
|1 to 6||25 to 150||4||5|
|Over 6||Over 150||5||6|
Table 3: Filter Lenses for Protection during Other Welding and Cutting Operations
|Operation||Arc Current (Amperes)||OSHA Minimum Protective Shade Number||ANSI & AWS Shade Number Recommendations*|
|Gas Metal Arc Welding (GMAW) and Flux Cored Arc Welding (FCAW)||Fewer than 60||7||-|
|More than 160-250||10||12|
|More than 250-500||10||14|
|Gas Tungsten Arc Welding (GTAW)||Fewer than 50||8||10|
|More than 150-500||10||14|
|Air Carbon Arc Cutting (CAC-A) (Light)||Fewer than 500||10||12|
|Air Carbon Arc Cutting (CAC-A) (Heavy)||500-1000||11||14|
|Plasma Arc Welding (PAW)||Fewer than 20||6||6-8|
|More than 100-400||10||12|
|More than 400-800||11||14|
|Plasma Arc Cutting (PAC) (Light)**||Fewer than 300||8||9|
|Plasma Arc Cutting (PAC) (Medium)**||300-400||9||12|
|Plasma Arc Cutting (PAC) (Heavy)**||More than 400-800||10||14|
|Torch Brazing (TB)||3||3 or 4|
|Torch Soldering (TS)||2||2|
|Carbon Arc Welding (CAW)||14||14|
* As a rule of thumb, start with a shade that is too dark to see the weld zone. Then, go to a lighter shade which gives a sufficient view of the weld zone without going below the minimum. During oxygen gas welding or cutting where the torch produces a high yellow light, it is desirable to use a filter lens that absorbs the yellow or sodium line in the visible light (spectrum) of the operation.
** Values apply where the actual arc is clearly seen. Lighter filters may be used when the arc is hidden by the workpiece.
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This is one in a series of informational fact sheets highlighting OSHA programs, policies or standards. It does not impose any new compliance requirements. For a comprehensive list of compliance requirements of OSHA standards or regulations, refer to Title 29 of the Code of Federal Regulations. This information will be made available to sensory-impaired individuals upon request. The voice phone is (202) 693-1999; teletypewriter (TTY) number: (877) 889-5627.
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DSG FS-3499 1/2012
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