In Arizona, a person’s blood alcohol concentration becomes illegal and dangerous once it hits 0.08 percent. For commercial drivers, anything above 0.04 percent is illegal. Naturally, for individuals under the age of 21, it is illegal to drink alcohol. That means even a BAC of 0.01 percent could send a teenager to jail for driving under the influence

Determining a person’s BAC without a Breathalyzer is next to impossible. A person’s BAC can vary wildly depending on the person’s age, gender and type of alcohol consumed. 

A serving of alcohol

A big reason why people should avoid driving after consuming any volume of alcohol is that many people do not understand what one drink truly is. For BAC purposes, one drink can either be 12 ounces of beer or 1.5 ounces of hard liquor. Therefore, a person consuming a mixed drink may not know how much of it is alcohol and how much is mixer. A drink that contains 2 ounces of hard liquor will make a person substantially more intoxicated than if it was at the standard 1.5 ounces. 

0.08 percent may not even matter

Although 0.08 percent is the legal limit, police can arrest someone even if the BAC is less. For example, some people have a few drinks without eating anything. Without any food, the person feels far more intoxicated than he or she would have otherwise. Believing it is safe to drive home, the person gets in the car and begins weaving between lanes. The police pull the person over. The BAC turns out to be less than 0.08 percent, but the person clearly displays all the telltale signs of intoxication. The police can still arrest drivers under these circumstances because they pose a threat to themselves and others. 

Understand limits

It is best for people to know their limits, so they do not drink too much and they recognize when it is time to find another way home. With numerous ridesharing apps available, there is no reason to risk an accident.