most people over estimate how long it takes for it to get out of your system but u can also smoke a lot and then drink water like crazy with vitamin B-2 or B-12 (to color ur piss yellow otherwhyes itll be watery and they might not accept it) and that will dilute it and will make your chances of it being under the limit even better but if you dont smoke for a few days and do that u shud definately be good