Isolation Fitting

[Okie Sparky]

Has anyone heard of an isolation fitting for conduit (rigid)? Where to get one, manufacturers name? I'd never heard of one until the pipeline company I do work for requested that we use them on our conduit when we come out of the ground and run along their meter skid. They say it messes with the cathodic protection of the pipeline. The piping (gas) on the skid is isolated from the underground pipeline, but our electrical piping is tied into the piping (gas) on the skid, then it goes underground to the instrumentation building. I see the problem, but where do I find the solution (isolation fittings)?, other than the good people at MH forums. I need trade sizes 3/4", 1" & 1 1/2". The fittings need to be Class 1 Div. 1 rated. Thanks in advance.