Failed my hair test, done by Labcorp (ELISA, the evil) Smoked ONE hit on 10/14, hair tested on 11/12- no precautions taken: failed with .22pg/mg reading. Weight 110, H 5'3, above average metabolism, thin blonde hair. Damn. Really wish I would have tried one of the methods preached on here...this is a custody case, and what sucks even worse is my ex, his family & friends are all heavy users. But my ex quit last year after 15 years so my one fk up is gonna cost me big time. Hating life right now. :/ I was worried obviously but figured with just one hit I'd be ok after all I read...and just barely failed! FML. Don't think ur ever out if the clear unless u test without the evil ELISA. That's my conclusion on it! And take precautions!!!