The major POCOs, in Wisconsin have required 22K AIC rated equipment for almost 20 years now. They typically feed (4) houses from a single padmount, so they could easily exceed the 10K fault level if they buy 2%Z transformers or put in an oversized one. This is one reason they give such high "design" fault values, to prevent future problems as they upgrade their equipment.
If you need 22K rated equipment make sure the branch circuits are either fully or series rated also. Do not just look at the AIC rating of the main.
What type of heat is he expecting on the GEC?
