The initial Immunoassay screen (as well as the home test) has a cutoff limit of 50 ng while the confirmation GC/MS has a cutoff limit of 15 ng.

But dont let the differing cutoffs worry you. Even though they numerically differ, a 50 ng I/A screen is functionally equivalent to the 15 ng GC/MS. For more info, read post #18 of this thread:

http://boards.cannabis.com/drug-test...ml#post2202713
Burnt Toast Reviewed by Burnt Toast on . How long Till I piss Clean??!!!?? I am 6.2 ft and weight 200lbs. I am skinny and active! however I am a chronic smoker, like a joint everyday. I have not smoke for two days wich is a big accomplishment for me! How long till I piss clean? I have read all the alternatives online, but i want to do it the natural way. no dilution, no fake pee, no aspirin, no B-12 vitamins. I know there is no exact way to tell how long, but is there anyone out there thats the same size as me that can help? Rating: 5