yeah, hair tests are rare. there is no set amount of time thc stays in your system. sense thc stores in your fat cells, it depends on your motabolisim, which was also mention. How much you smoke, and how good the weed is are also big factors, as well as your regular smoking patter. But don't quit smoking just because you have a piss test, be smarter than the fucking cup you dumb ass. Find out where the test is going to be, research and find out how they test you, are they in the room with you? do they listen through the door? do you have to empty your pockets. The best and easiest way to pass a test is to substitute. the day off or even a couple days before if you have a fridge, get one of your pussy ass straight edge friends that doesn't smoke to pee in a cup, insert clean pee into condom, tie a know, find a pair of boxer briefs, or tighty whities if you still can fit in any, add skiing handwarmer for the temp check, conceal in briefs, enter room take out condom, either untie the knot, or poke/cut a small hole (faster than untie) with a device concealed in your shoe, spray a stream into the cup, then in the bowl, and a little on the seat, and floor because the bitch working there has to clean it up, conceal condom back in shoe, get your job or what ever you are being tested for.
If you like Jack Johnson, O.A.R., Dispatch type music check out Speechwriters LLC
http://www.speechwritersllc.com