What You Need to Know About BAC

Odds are, you have heard the term BAC before. But do you really know what it means and what it entails? Your knowledge could be the difference between life and death or jail time and freedom.

Blood alcohol concentration, also known as Blood Alcohol Content (BAC), is a measure of the amount of alcohol in a person’s bloodstream. This metric is often used by law enforcement officers to determine if a person is in the right state of mind to drive. Here are a few things you need to know about BAC.

There is a Legal BAC Limit

Many countries have a BAC benchmark. Similarly, in the US, all states have a BAC limit. Drivers aged 21 and over are alcohol-impaired if their BAC is 0.08% or higher. A 0.08% BAC means that there is 0.8 part alcohol content for every 1000 parts of blood. At that level, the body experiences drastic changes, including:

  • Poor muscle coordination
  • Slurred speech
  • Dramatic mood swings
  • Poor decision making
  • Impaired vision
  • Loss of memory

If you cross that 0.08% limit, you are ineligible to drive. Police officers will arrest and charge you if you do so. You may end up with various sanctions ranging from a fine, suspension of your license to, at worst, jail time. A high BAC is fatal and can lead to death or severe medical conditions. For instance, a BAC of 0.25 – 0.35 will result in loss of motor coordination, mental confusion, and dysphoria. A BAC of 0.40 could result in a loss of consciousness, coma, and respiratory failure.

While the legal limit remains 0.08%, there are calls for a reduction in the legal limit. The National Transportation Safety Board (NTSB) has been leading the requests, arguing that lower BAC limits would help reduce the spate of drunk driving accidents.

Various Factors Affect BAC

Just as everyone’s metabolism is unique, people process alcohol in varied ways. Consequently, you may drink the same amount of alcohol with someone, but you may both end up having different BAC readings.


Generally, the BAC of women rises faster than men. This trend is valid for several reasons. First off, men have 61% water content in their body compared to 52% in women. This data means that men can dilute alcohol content faster. Also, women generally have higher body fat than men; men tend to have more muscle in their bodies. Because alcohol doesn’t dissolve in fats, the BAC in women tends to be higher than men who consumed the same amount of alcohol.

Body Size

A larger body size means that you are likely to have more body fluids to dilute alcohol. That’s why people with a large body size tend to be slower at reaching high BAC levels than people of smaller stature.

Food in Stomach

The amount of food in your stomach will affect your BAC. Because the body absorbs alcohol through walls of the stomach, the presence of food reduces alcohol absorption. That’s why getting intoxicated on an empty stomach will result in higher BAC reading.


Of course, you’re going to get drunk if you go for drinks with higher liquor content. Also, the faster you drink, the faster your BAC rises. If you drink too much at a sitting, the body will be overburdened, as it has to metabolize all you’re drinking.

Alcohol Tolerance

For some long term alcohol drinkers, their liver grows more adept at metabolizing alcohol. Therefore, they show fewer signs of intoxication. And it may take more drinks than usual for them to begin to act intoxicated. However, even if you have a higher alcohol tolerance, you still need to take precautions while drinking.

It Can Be Measured in Different Ways

There are several ways alcohol can be detected in your breath. The most common way is the use of a breath analysis device, also known as a breathalyzer. There are several breathalyzers online that you can easily purchase. These devices are simple, portable, and easy to use tools to check your BAC. All you have to do is to take the device, breathe into it, and it will display your BAC.

Alternatively, you can measure your BAC through a blood test. This method delivers more accurate results than breathalyzers. Urine tests, on the other hand, are less reliable than breathalyzers and blood tests. They are often regarded as intrusive and only used when the earlier mentioned methods are not possible.

Your Life and that of Others is at Stake

Each day, several people die from drunk driving accidents. Drivers can avoid most of these accidents if they know their BAC. Before you head over to a bar or pub or any place drinking is likely to occur, make arrangements for a replacement driver. Alternatively, use cab-hailing services such as Uber. This move will ensure your safety and that of others on the road.