What can affect a Breath Analyzer?

DUI Lawyer

If you’ve been charged with DUI, the breath analyzer results will likely be a large part of the case against you. Your DUI lawyer is aware of many factors that can affect a breath analyzer reading, and you should be too.

First, you should understand how a breath analyzer works. When you blow into the machine, the ethanol (alcohol) in your breath is oxidized at the anode to form acetic acid. At the machine’s cathode, oxygen is reduced into water. These simultaneous reactions produce an electrical current, and that current is used to estimate your BAC (blood alcohol content).

It’s important to know that the breath analyzer device is not actually able to measure the amount of alcohol in your blood, since it doesn’t have access to your blood. It can only measure the amount of alcohol in your breath and then extrapolate your BAC.

Because it is only an estimate, it may not accurately reflect the true amount of alcohol in your body. Your DUI lawyer will explain to you just how inaccurate a breath analyzer can be.

Your Metabolic Rate: If you have a slow metabolism, your body will absorb alcohol more slowly (just like it does everything else). This means that the actual amount of alcohol in your bloodstream is less than the amount that the breath analyzer projects, and you may not actually be over the limit.

Your Body Temperature: Most breath analyzers are calibrated to be accurate at 34 degrees Celsius, which is 93.2 degrees Fahrenheit. Research has shown that most breath analyzer tests in the field actually come closer to 35.5 degrees Celsius (95.9 degrees Fahrenheit). In a hot and humid Maryland summer, your breath could easily be even warmer than that! This discrepancy can result in a reading that is up to 20% higher than it should be.

Alcohol in Your Mouth: Since the breath analyzer measures the amount of ethanol in your breath, any residual alcohol in your mouth will result in a significantly higher reading. Police officers are required to wait at least 15 minutes after pulling you over to allow any alcohol in your mouth to dissipate. If they don’t do this, the reading could be inaccurate. Also, if you belch or vomit, that can increase the amount of alcohol in your mouth.

Your Job: As already explained, the breath analyzer device measures the amount of alcohol in your breath. It is not able to differentiate between ethanol (the alcohol you drink) and acetone. People such as woodworkers and nail technicians who are exposed to high levels of acetone may end up with breath analyzer readings that are higher than they should be.

Your Health Conditions: Certain chronic health conditions may also result in inaccurate breath analyzer readings. People with diabetes often have acetone on their breath from ketoacidosis, and as explained above, the breath analyzer cannot distinguish between acetone and ethanol. (The keto diet can also cause ketoacidosis.) People with gastroesophageal reflux disease are likely to have undigested alcohol in the stomach and also to be burping before the test, both of which can result in high breath analyzer readings.

Breath analyzers are not new science. Nearly a century ago, they were marketed to housewives so that they could monitor their husbands’ drinking habits. By 1931, the “drunkometer” was being used in roadside sobriety tests. Your DUI lawyer knows all about them and their inaccuracies. Reach out to Cohen & Cohen Attorneys to learn more.