In most cases it's just regular gas pumps, with nothing specifically to prevent you from serving yourself. Usually there's someone standing there as you pull up

In most cases it's just regular gas pumps, with nothing specifically to prevent you from serving yourself. Usually there's someone standing there as you pull up, but if it's cold, or if it's not super busy they may be inside. If you forget the rule and start pumping your own gas, someone runs out with a slightly panicked look and says "this is Oregon, this is Oregon!"