actually, my friend didnt smoke for over 2 months and then he smoked like 3 hours before his parents randomly tested him (just really bad luck) and he still failed.. so i dont htink it takes 24 hours
geoffrowley19 Reviewed by geoffrowley19 on . My method for passing tough tests I posted this as a reply in another thread, but I think others could benefit from this: The best way to clean up really fast is like this: 1. About 4 hours before the test, drink about a gallon of water. This is very hard, I know (it used to make me shiver when I did it because of all that cold fluid). 2. Go to the bathroom at least once before you take the test, preferably two or more times. Don't worry about having enough pee to take the test, because all of that water will take Rating: 5