too reflexive to be easily quantified. But honestly I draw pretty lightly when lighting the pipe as well as smoking it. Big hint you do know the flame doesn't have to touch the tobacco to light it? In fact you get a cooler smoke if the flame is either not touching or barely and briefly touching the tobacco (as in shallow contact and not for long). Best to not over think a pipe but like most things pipe related what's one mans over thinking is some other guys or ladies having fun nitpicking. But asking us something like this isn't that different then asking someone how much force they use when chewing different foods. Most people aren't going to be able to say they bite into a steak 1.5 times as hard as they bite into a piece of chicken.