Coulter-
That's pretty good. That's what I was thinking but I didn't have a code reference in mind. Since you had the best answer, I'll provide the blah, blah, blah:
501.15 Sealing and Drainage
4) Class I, Division 1 Boundary
In each conduit run leaving a Class I, Division 1 location. The sealing fitting shall be permitted on either side of the boundary of such location within 3.05 m (10 ft) of the boundary and shall be designed and installed so as to minimize the amount of gas or vapor within the Division 1 portion of the conduit from being communicated to the conduit beyond the seal. Except for listed explosionproof reducers at the conduit seal, there shall be no union, coupling, box, or fitting between the conduit seal and the point at which the conduit leaves the Division 1 location.
Exception No. 1: Metal conduit that contains no unions, couplings, boxes, or fittings, and passes completely through a Class I, Division 1 location with no fittings less than 300 mm (12 in.) beyond each boundary, shall not require a conduit seal if the termination points of the unbroken conduit are in unclassified locations.
Exception No. 2: For underground conduit installed in accordance with 300.5 where the boundary is beneath the ground, the sealing fitting shall be permitted to be installed after the conduit leaves the ground, but there shall be no union, coupling, box, or fitting, other than listed explosionproof reducers at the sealing fitting, in the conduit between the sealing fitting and the point at which the conduit leaves the ground.
wnbeaty-
There is more to this article of coarse but this is the part that answers your question. Me personally, I like using Cooper Crouse-Hinds Code digest which has pictures
, part numbers and code language all in one place. I know you don't have a "local" Crouse-Hinds dealer (or maybe you do) but you'll have to get the parts from somewhere. They would be happy to give you one of these.
Best of luck and stay safe out there. I know YOU are risking your life to!