After 5 hours – your BAC would be 0.005. Alcohol would be eliminated from the body at about 5 hours and 20 minutes (the body metabolizes alcohol at the rate of about 0.005 per twenty minutes, as 0.005 x 3 = 0.015). So it is easy to tell when your body will be free of alcohol. It is not so easy to tell, however, what your BAC is if you do not have some kind of alcohol tester, be it a breathalyzer or a disposable alcohol test. Getting to a BAC of 0.08 is not that difficult. For a 140 lb man, it would be 3 drinks in one hour.