After all, the whole point of ATEX certification is that it doesn't make a fire. One would think if you can safely use something in an explosive atmosphere you can use it on shabbos. By the same token a shabbos light should be safe to use in an explosive atmosphere.
When I was in fourth grade, the science teacher taught us the physics definition of work and explained how it differs from the everyday definition of work Much like that -- Jewish legal definitions of Hebrew words do not always line up perfectly with the everyday use of English words that aproximate them. With electrical items, the prohibition of fire is only one of the prohibitions to be aware of for Shabbat -- off the top of my head, there is also boneh (building) and bishul (cooking) On the reverse side -- your logic does not hold in even the most basic English definition. It is only the Karaites that believe there is a Shabbat prohibition of fire, the normative prohibition is on making fire and putting out fire -- thus, there are quite a few devices used on Shabbat that are straight forwardly on fire (well, heck -- just think of the candles themselves!!!) A Shabbat lamp is simply always on - but has some cover to keep the light from bothering. Hopefuly, this whole structure is well insulated (I don't know -- never used one)
