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This line of discussion makes me curious. I have a number of lights that I know would/could/might might make contact spark with sliding contacts. Rotary contacts I would not think would be any different.


I don't think it has to do with what type of contact. It is the fact that in the dive lights that the contacts are on the inside of the waterproofing.

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What about the solid state lights like the Photos? I would not think that they are a potential ignition source.


I don't think they are intrinsically any safer or less safe. Keep in mind their are fairly large differences in design between the Photon models. For example, the Photon I & II have no waterproofing and I would say they would be very bad choices for flamable gas. On the other hand, the Photon III has some waterproofing and would probably be much better.

On the other hand, personally, I'd look to lights like the UK MiniQ40 or UK 2L for this type of service. I'm not sure what the ratings on these lights are, but they are mega-waterproof, plastic (no spark if dropped).

-john