Skip to Content
Call Us Today! 860-455-4202

Important facts about breathalyzers and blood alcohol content


As we approach Fourth of July weekend, law enforcement will be out in force with the expectation that people will have one (or a few) too many drinks at a party or other event and then get behind the wheel. When people are pulled over on suspicion of DUI for the first time, and particularly if they're charged with one, it's a frightening experience. All of a sudden, terms they've only heard before like "breathalyzer," "blood alcohol content" (or concentration) and "blowing a .08" become all too real. Let's take a look at what those mean and how they can impact your life.

Breathalyzers that are used in field sobriety tests can measure the level of alcohol in a person's body because as alcohol is consumed it gets into your blood. As the blood moves through the lungs, it goes into the membranes and air sacs. The concentration of alcohol there correlates with that in the blood. Therefore, when you breathe into a breathalyzer, the amount of alcohol in your blood can be determined.

Blood alcohol content, or BAC, is the percentage of alcohol in the blood. The legal limit is .08. Therefore if you "blow a .08," that generally indicates that if a sample of your blood were to be taken, it would contain .08 percent alcohol. Of course, blood tests are another way to determine whether a person is under the influence. However, that involves going to the hospital.

Alcohol is absorbed into the system differently depending on a number of factors. If you and a friend both have two martinis made identically, they could affect you very differently based on things like:

-- How much you weigh-- How much food you've consumed-- Whether you've consumed water and how much-- How fast you drank the alcohol

Of course, breathalyzer tests aren't infallible. The machine has to be calibrated properly and the test must be administered correctly. Further, there are other things, like cough medicine, that could tip the scales over the legal limit. There can also be very different legal ramifications for having a .08 BAC and a .12 or higher. That's why if you find yourself charged with a DUI, it's essential to have legal guidance from a Connecticut attorney with experience handling DUIs in your county who can examine the evidence and work to protect your rights.

Source:, "Blood Alcohol Concentration and Breathalyzers: How It Works," Jessica Guerin, accessed July 01, 2016