USA analogue of EU Gastronorm standard

I haven't been able to find an official standard for US sized pans... the wikipedia even state : "used worldwide except in the United States, which has its own domestic system" but does not link to any reference to that system.

This seems to indicate that the Gastronorm was based on existing US standard :

"At this meeting the basic size of 530 x 325 mm, already in use with American standard steamable pans, was accepted."

This lists a series of sizes that seem to be accepted nationally in the USA and says that : "Gastronorm sizes are comparable to American sizes and can generally be interchanged." (bold by me)

So you can safely use GN sized pans everywhere.