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The intense light associated with welding operations can cause serious and sometimes permanent eye damage if operators do not wear proper eye protection. The intensity of light or radiant energy produced by welding, cutting or brazing operations varies according to a number of factors including the task producing the light, the electrode size and the arc current. The following table shows the minimum protective shades for a variety of welding, cutting and brazing operations in general industry and in the shipbuilding industry.
Table 1
Filter Lenses for Protection Against Radiant Energy
| Operations |
Electrode size in 1/32" (0.8mm) |
Arc current |
Minimum* protective shade |
| Shielded metal arc welding |
< 3
3 - 5
5 - 8
> 8 |
< 60
60 - 160
160 - 250
250 - 550 |
7
8
10
11 |
Gas metal arc welding
and flux cored
arc welding |
< 60
60 - 160
160 - 250
250 - 500 |
7
10
10
10 |
Gas tungsten
arc welding |
< 50
50 - 150
150 - 500 |
8
8
10 |
| Air carbon |
(light) |
< 500 |
10 |
| Arc cutting |
(heavy) |
500 - 1,000 |
11 |
| Plasma arc welding |
< 20
20 - 100
100 - 400
400 - 800 |
6
8
10
11 |
| Plasma arc cutting |
(light)**
(medium)**
(heavy)** |
< 300
300 - 400
400 - 800 |
8
9
10 |
| Torch brazing |
3 |
| Torch soldering |
2 |
| Carbon arc welding |
14 |
Table 1
Filter Lenses for Protection Against Radiant Energy
| Operations |
Plate thickness inches |
Plate thickness mm |
Minimum* protective shade |
Gas welding:
Light |
< 1/8 |
< 3.2 |
4 |
Gas welding:
Medium |
1/8 - 1/2 |
3.2 - 12.7 |
5 |
Gas welding:
Heavy |
> 1/2 |
> 12.7 |
6 |
Oxygen cutting:
Light |
< 1 |
< 25 |
3 |
| Oxygen cutting: Medium |
1 - 6 |
25 - 150 |
4 |
Oxygen cutting:
Heavy |
> 6 |
> 150 |
5 | Source: 29 CFR 1910.133(a)(5).
* 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 sufficient view of the weld zone without going below the minimum. In oxyfuel 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 of the (spectrum) operation.
** These values apply where the actual arc is clearly seen. Experience has shown that lighter filters may be used when the arc is hidden by the workpiece.
The construction industry has separate requirements for filter lens protective levels for specific types of welding operations, as indicated in the table below:
Table 2
Construction Industry Requirements for Filter Lens Shade
Numbers for Protection Against Radiant Energy
| Welding Operation |
Shade Number |
Shielded metal-arc welding
1/16-, 3/32-, 1/8-, 5/32-inch diameter electrodes |
10 |
Gas-shielded arc welding (nonferrous)
1/16-, 3/32-, 1/8-, 5/32-inch diameter electrodes |
11 |
Gas-shielded arc welding (ferrous)
1/16-, 3/32-, 1/8-, 5/32-inch diameter electrodes |
12 |
Shielded metal-arc welding
3/16-, 7/32-, 1/4-inch diameter electrodes |
12 |
| 5/16-, 3/8-inch diameter electrodes |
14 |
| Atomic hydrogen welding |
10 - 14 |
| Carbon-arc welding |
14 |
| Soldering |
2 |
| Torch brazing |
3 or 4 |
| Light cutting, up to 1 inch |
3 or 4 |
| Medium cutting, 1 to 6 inches |
4 or 5 |
| Heavy cutting, more than 6 inches |
5 or 6 |
| Gas welding (light), up to 1/8-inch |
4 or 5 |
| Gas welding (medium), 1/8- to 1/2-inch |
5 or 6 |
| Gas welding (heavy), more than 1/2-inch |
6 or 8 |
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Hard Hats
Hearing Protection
