Posted By John Murgatroyd 1. No. 2. Yes, but it's dependent on distance and how long someone looks at the arc. Don't take a chance, it isn't your eyes. Welding areas should be surrounded by screens that totally shield others from the arc, the screens should be a dark and matt colour (white reflects the UV radiation, so does a gloss finish) You'll need a decent amount of ventilation, depending on the type and quantity of welding and you may even need local extraction for the welding bay anyway. The welder/s will also need some form of protection from fume AS local extraction. Welding Booths and Welding Bays a) Welding Bays: Where arc welding is regularly carried on in a building, the walls of the welding bay should be painted with a finish of low reflectivity. b) Welding Booths: Arc Welding. The worker should be enclosed in an individual booth painted with a finish of low reflectivity, or shall be enclosed with noncombustible screens similarly painted. Booths and screens shall permit circulation of air at floor level. c) Adjacent Work Spaces: Arc Welding. Workers or others adjacent to the welding areas shall be protected from the rays by noncombustible screens or shields or shall be required to wear appropriate goggles

Posted By Smurfer I had a similar query earlier this year regarding a 'safe distance' and found this reference, which includes a statement that "without effective screening, other personnel up to distances of 30m could be at risk" from optical radiation (UV & blue-light). Yes - 30m!! The 'ceiling-level' for infra-red radiation, however, is not likely to be exceeded for the welder. "Review of occupational exposure to optical radiation and electric and magnetic fields with regard to the proposed CEC physical agents directive" National Radiological Protection Board S G Allen, R P Blackwell, P J Chadwick, C M H Driscoll, A J Pearson, C Unsworth and M J Whillock Sheffield ; London : HSE, 1994 I can't really help on the polycarbonate sheeting query, but you may be able to check with the manufacturer on its UV/IR screening capabilities. Hope this helps.

Posted By AlB I'm no expert on welding and I need to do a lot of research into it, but it amazes me the ignorance of some of the welders I have come accross. I've seen welders working for our company ARC welding, with other fitters within 10m, but no screens erected. When I approach them, I get the response - "they'r too far away to get a flash, so I don't need to put up a screen". Needless to say, they get a lesson in the reality of the situation, and they put up a barrier. Only this morning I came accross a contractor Arc welding some steel onto one of the conveyor structures. The conveyor was not isolated - in fact the conveyor was moving at the time!!!, they had no screens up, and there were people unloading the conveyor no more than 1.5 metres away from them! When I stopped the work and queried them, one of them said "I shield the welding flame with my hands, so I don't need to put up a screen". Are these people for real!!!??? If anyone has any further information on welding (especially ARC welding), I'd be greatful.... Thanks.