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 Post subject: You can not perform any flash arc work with contact lenses .
PostPosted: Mon Jan 07, 2019 6:04 pm 

Joined: Fri Jul 10, 2009 10:14 am
Posts: 27
Location: West Central, OH
Don’t know where the above statement is from but is it true? I have not heard about in any of the training classes I have attended.

The real question is a person with an artificial lens surgerlly placed during cataract removal surgery’.

Any concerns or consideration for this person?


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 Post subject: Re: You can not perform any flash arc work with contact lens
PostPosted: Tue Jan 08, 2019 10:48 pm 
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Joined: Tue Oct 26, 2010 9:08 am
Posts: 2174
Location: North Carolina
Never seen any evidence for it. It is in direct contact with the fluids of the eye. Assuming you follow the rest of it, you're already wearing safety glasses and goggles or a face shield or a hood. How is the heat transwer going to affect such a thing to the point where it melts or deforms?

I would believe that if you watch some of the arc flash videos where they show a non-arc rated face shield melting and burning you could get the impression that this is true of all plastics. But it doesn't take into consideration the fact that you are referring to something that is in direct contact with a fluid that would have to be boiled off first before it could get to a temperature where melting is a concern, at which point the eye is destroyed anyway.

Sounds like yet another rumor started somewhere.


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 Post subject: Re: You can not perform any flash arc work with contact lens
PostPosted: Wed Jan 09, 2019 7:22 am 
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Joined: Mon Jan 18, 2010 11:35 am
Posts: 514
Location: Wisconsin
PaulEngr wrote:
Sounds like yet another rumor started somewhere.


Most likely from the old rumor that UV light from a welding arc would also cause contacts to stick, or fuse, to the eyeball.

It seems many safety people have a hard time with the concept of probable vs possible, to the point I wonder how many lottery tickets they buy.


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 Post subject: Re: You can not perform any flash arc work with contact lens
PostPosted: Thu Jan 10, 2019 11:04 am 
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Joined: Tue Oct 26, 2010 9:08 am
Posts: 2174
Location: North Carolina
JBD wrote:
PaulEngr wrote:
Sounds like yet another rumor started somewhere.


Most likely from the old rumor that UV light from a welding arc would also cause contacts to stick, or fuse, to the eyeball.

It seems many safety people have a hard time with the concept of probable vs possible, to the point I wonder how many lottery tickets they buy.


Probabilistic safety is pretty much where the modern safety approach has gone to. I work in maintenance. Do you know how many times I've been asked the question can you guarantee X? To which the standard reply is there are no guarantees in life.

Realistically the modern approach is two fold. First we ignore all the safeties that change the probability of an outcome or in some cases even those (passive protections) and then we apply all the safeties and estimate likelihood. Then based on these two factors we look at whether or not the risk (combination of likelihood AND magnitude) are acceptable or not. Generally the goal is to achieve a likelihood of one in a million (per year) or less often of a single fatality which is generally where shock hazards are. As we ratchet back from that outcome we can gradually accept higher likelihoods for lesser injuries. For instance a hospital stay might be 1 in 100,000 which is where arc flash is, all the way up to paper cuts.

However there are to caveats that make this hard. First off a lot of safety folks struggle with the two factor approach and constantly try to lump things together. They get a god complex and believe they are alone in a crusade to save the world from themselves, and will stop at nothing to achieve it. They get hung up on the morbid side and ignore the rest. The second and more severe problem is the Ethics Code for professional engineers that specifically calls for taking a "conservative approach" to everything. So they turn their brains off and view everything from an extreme absolutist point of view regardless of the consequences. In electrical engineering this is understandable. Generally it is fairly easy and inexpensive to beef up the structure to achieve a higher AIC, use a bigger breaker, etc. But in other engineering fields particularly the "soft" types such as materials engineering, chemical engineering, and the like, this "bigger hammer" doesn't work. At one time both were declared chicken littles and ignored but in today's litigious environment this approach actually gets credibility.


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 Post subject: Re: You can not perform any flash arc work with contact lens
PostPosted: Mon Jan 14, 2019 9:06 am 
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Joined: Sun Jan 04, 2009 5:00 pm
Posts: 283
Location: Louisville, KY
This keep coming up. We at e-Hazard and ArcWear have done some testing and research. Here is an article on the findings and tests.

https://www.e-hazard.com/blog/contact-lens-arc-flash/

Hugh Hoagland


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 Post subject: Re: You can not perform any flash arc work with contact lens
PostPosted: Sat Jan 19, 2019 7:40 pm 

Joined: Fri Jul 10, 2009 10:14 am
Posts: 27
Location: West Central, OH
Thanks for all the responses.


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