[Jon72]

You could start with The Petroleum (Consolidation) Regulations 2014 but there will be others too.

Edit: actually, I see what you meant now. There are no rules about time limits waiting at petrol pumps (that I know of) and I didn't mean to imply that there were. I was talking more widely about the need for us to establish normal rules of use.

That law is about the safe storage and dispensing of petrol as a dangerous substance.

Hardly the same as passing a law to make bad manners illegal.