About an hour. It is roughly a drink per hour you will decline and one beer puts you at .02 and you drop anywhere from .015 to .02 per hour depending on weight gender and liver function
After Drinking Beer, How Long Does It Take To Blow A .0?
It depends on the rate of absorption (if you have eaten lately), how much you drink and your build/weight. Normally 2 hours per beer is good to be legal but it may be longer until you blow a 0.
Six to twenty four hours.