The BAC limit in Louisiana is same as in the most of other states – 0.08 for general drivers, 0.02 for under-21 drivers, and 0.04 for commercial drivers. Certain Louisiana drunk driving penalties will be applicable if you are caught while driving under the influence of alcohol with a BAC level of more than the allowed limit. It is also important for you to keep in mind that Louisiana also makes it mandatory for all drivers to take chemical test when the traffic officers ask them for it.