was working near rotherham a couple of years ago inspecting a rather large gas pipe over a river, which included the steel structure around it. one of the tests was basically hitting both these structures with a hammer. upon reaching the far side i smelt gas and told mate to stop work. i shouted down to the expert sub contracting for the gas company and told him why we were stopping etc. he said if i feel i should stop then stop but he was clearly getting agitated about this possibility. i had to ask him 3 times if he really wanted me to hit the steel pipe with the steel hammer in the presence of a gas leak