I've seen some articles about using pex for natural gas lines, especially buried underground. If so, can you use standard non barrier pex, or does it have to be rated and colored differently?
for direct burial for natural gas and propane generators . We use these long sweep transition ells to come out of the ground . I think they're painted galvanized and have IP threads on one end and either a compression fitting or shark bite type fitting on the other end for the yellow pipe . Passes all codes where we work on Long Island .