Of all the fueling island canopies that I have worked on, at least here in the Illinois, Wisconsin, Indiana area, there is usually an explosion proof seal off in or on one of the support columns. From there, we did run rigid [GRSC] up to the top of the canopy. At that point, we would transition to EMT, compression fittings and weatherproof, [Bell] boxes. It has been about a decade since I've done one. At that time, we used a surface mounted 2 x 2 metal halide fixture with a dropped prismatic lens. Mobil gas stations had a unique canopy with a "roof" over the top of the steel stucture, from which, you had to remove full length steel panels to gain access. It was a lot of work, but they were always in better shape.
Recently, the trend has been to use recessed or semi-recessed metal halide fixtures. The new BP canopies are a neat looking breed, [at least for new stations], and I can't speak to those.
As a last aside, the area I come from is generically a pipe and wire are only. Plastic is rellagated to underground uses, but of course, not for hazardous location work.
As PS, the plans call for rigid, [GRSC], do you have the latitude to use something else? Perhaps the GC or the oil company rep won't ever check, but if the plans call for one material, isn't the customer expencting that? Perhaps I've been working for municipalities for too long, but if you didn't ask for a change, offer a credit, or get approval, you would be back, changing out the materials for those speced, and waiting for your money.
[This message has been edited by US Coreman (edited 05-26-2003).]