Rank: Forum user 
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Hi All,
Quick one. Completing RA for TIG welding processes on site. Workshop is fine but one issue that i'm a little unsure of is welding in external location that could be wet from weather conditions or TIG welding inside factory were there will be wet conditions (food manufacturing). Welding usually happens post production and prior to washes for quality reasons but generally the environment is is wet due to the process.
What control procedures would be best for these types of tasks apart from ensure area is completely dry (if very difficult to achieve).
Thanks,
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Rank: Super forum user 
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Why do you want the area dry apart from quality reasons?
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Rank: Super forum user
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For welding in wet conditions you need to choose a set with the correct IP rating for the conditions you will find - e.g. IP21 for dripping water.
It is not unheard of for welders to be fatally electrocuted in conductive environments. It is advised to have a set where the open circuit voltage is restricted., e.g. below 48V rms or 113V DC. Sets that have been manufactured for this service have a letter 'S' on their rating plate. You can also get voltage reduction devices, I believe.
Electrode holders and connections need to be fully insulated and the welder needs to keep dry and minimise the amount of skin exposed!
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Rank: Super forum user
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Jane,
To get electrocuted, you need to complete a circuit.
The bit about the welding plant being suitable for me was not even a consideration because that is essential!
I only considered the actual point at which the welding is to be undertaken.
If there is an earth path from the welding circuit "earth" connection back to true earth then you can have an issue.
However, if the part being welded is not connected to true earth, neither is the secondary side of the transformer then there is no path back from the "live" side of the transformer for the current to flow.
The welder using a TIG set should at no time be in contact with any "live" parts connected to the "live" side of the weldign set secondary.
Limiting the output to ELV values is a possibility, though that may have an affect on the welding process itself.
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Rank: Super forum user
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The 'S' type of welding set is special, the OCV of ordinary sets is much higher.
I would anticipate there is a lot of earthed metal inside a factory, especially a food factory.
That is how the welder at a pet food manufacturer was killed. I agree that it might be less likely with a TIG set than when doing MMA welding. It is believed the operator was killed when changing electrodes.
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Rank: Super forum user
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Not seen that with ordinary a.c. transformer sets Jane, do you have a further reference to this 's' mark?
On "clever" inverter type advanced a.c./d.c. MMA/TIG power sources, yes, standard a.c. transformer type supply not seen this facility.
In a restricted conductive location then there will be issues.
Then the welding set must be located outside the zone anyway, also as the welder is likely in intimate contact with the material being welded then also this will be an issue.
There still should be separation between the secondary circuit and the earthed metal work of the building though, that is unless the welding return lead, which is probably a better way of describing it even though it is commonly called the earth lead is connected to the general earthed metal work, then the welder could get a path from the welding "live" lead through the electrode in the holder as he is changing it and back to the transformer secondary via the interconnected metal work in the building to the welding return lead side of the transformer secondary.
The return lead should be connected as close as possible to the weld point as the currents running through the building steel work and other wiring could cause damage or fires, also, there can be EM issues for sensitive electronic equipment.
Then there is the differing physiological affects of d.c. / a.c. / modified a.c. to consider on the human body...
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Rank: Super forum user
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It is all in the standard for Arc Welding power supplies, BS EN 60974-1:2005
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Rank: Super forum user
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Rats Jane,
I don't have access to that standard!
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Rank: Super forum user
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You can buy it from BSI
Jon
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Rank: Super forum user
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John,
I realise that, but at over £200 then it's a non starter, just for curiosity at this stage!
It's not one of the standards that I have had to refer to previously as it's more of a product standard.
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Rank: Forum user
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Hi Paul,
Good tip I picked up from this forum a while back was that the standards can be accessed online for free from your local library (via your local .gov website). All you need is library membership.
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Rank: Super forum user
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There is a brief mention of the standards for welding sets for use in conductive (e.g. wet) environments in HSG 204. Somewhat cheaper than the BS.
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Rank: Super forum user
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