Safe Distance from Welding Arc

By gman Date 10-22-2001 15:25

What is the distance from a welding arc where eye injuries are no longer a risk?

I am a safety manager for a large project in Southern California. We are building a 10 story structural steel building on a college campus and have numerous people stopping to watch the work. Most are at least 60 to 100 feet away from the structure at the moment, but later parts of the structure will be closer to public areas.

Since we will have close to 60 welders at the peak of steel operations it may not be practical to manage 60 guys with welding screens. It will also be impractical to drape the entire building with protective material.

I have not been able to find any guidelines in Federal or Cal/OSHA regulations that outline a safe distance. There is nothing that refers to public exposure since OSHA regulations are designed for employee protection.

Are there any scientific guidelines that apply to safe distances from an arc from another source like medical research? I have read the posts from July that refer to eye protection for employees. We have dealt with exposure for employees on the site already.

Any help is appreciated!

Greg M.

By bhiltz

Date 10-22-2001 18:10

By boilermaker On 02-Jul-01 17:17
[Reply]

A safe distance is 50 feet.

By Lawrence (*****)

Date 10-23-2001 13:47

Your question is a good one and I too would like to see a "sourced" responce to it.

In the meantime I would advise you to contact Cal-Trans, who have been doing massive welding projects in the way of bridge retrofits all over the state.. I have seen many open welding Arcs on these projects. Now I am assuming that I was allowed to see them because I was at a safe distance. They have all the money and if a curtain was required for every weld they would have a curtain on every welder. So following this train of thought they outta have your answer. Make sure your data is sourced and that you have an up to date hard copy.. I cant even guess what the liability of scorching the retinas of some poor group of liberal arts majors would cost in the end :)

By gman Date 10-23-2001 21:23

The owner's safety rep for our project spoke to his Ophthalmologist who told him that 50 feet was applicable. He couldn't give a quotable source, but was going to do some research on it. He did confirm the information about the exponential increase and decrease in distance from the arc. His comment was that at 50 feet the exposure is mitigated. He did recommend not staring at the arc though…

I’ll post any confirmation I can find.

Greg

By TimGary (****)

Date 10-24-2001 01:39

I have also wondered about the "safe distance" and have another question as well...
I have been told that If a person wearing the soft plastic disposable contact lenses watches a welding arc long enough to receive even a minimal flash burn, the lenses will stick to the retina and result in blindness.
Does any one know if this is true and if so what would be the safe distance in that situation?

By gman Date 10-24-2001 14:36

There is no proof about the contact lens melting theory. This is a link to an AWS fact sheet that addresses that issue: http://www.aws.org/technical/FACT-PDF.EXE/FACT-12.PDF

Besides that, no one should stare at a welding arc for any amount of time. Even beyond the distances we’re trying to establish. Employees in a work area 50 feet or closer must be protected with either a shield used by the welder or with appropriate eye protection per OSHA standards, regardless of whether they wear contact lenses.

By GRoberts (***)

Date 10-24-2001 14:45

The "Safety and Health of Welders" book from the Hobart School of Welding Technology has the following passage.

"The wearing of contact lenses by welders is the subject of erroneous and recurring rumors. Various authorities including the National Society to Prevent Blindness, the Contact Lens Association of Opthalmologists, and others state that the normal eye protection required by OSHA for welding, brazing and soldering is the same with or without contacts. The American Optometric Association adopted a policy statement saying that contact lenses may be worn in hazardous environments with appropriate normal safety eye wear. Cantact lenses of themselves do not provide eye protection in the industrial sense. As a general rule, if an employee habitually wears contact lenses, they should be allowed to wear thier lenses in addition to normal safey equipment. It was further noted that the heat from a welding arc or flash is not intense enough to affect the durable plastic from which contact lenses are made. Welders or anyone who may be exposed to a welding flash or arc should wear appropreate safety goggles over thier contact lenses. Eye experts unanimously agree that it is impossible for an electric arc to weld contact lenses to the eye. The American Optometric Association says that reports of this hazard are based on rumor and have been thoroughly discredited. Both OSHA and U.S. FDA stated that the reports of this acciden were false and there is no such danger."

It doesn't mention anything about safe distances for bystanders though.

G Roberts