I've just started working in a workshop and I've seen these compressed air hoses that are used to clean materials and I was wondering: 1. How much pressure should the compressed air have for it to push someone? However with enough pressure coming inside that tiny outlet I believe it might damage someone/ pop a hole right through them, which brings me to my second question: 2. How big does he diameter of the outlet has to be to be able to push someone without inflicting damage? (of course not taking into consideration what could happen to the poor guy after getting blown) Thanks in advance.