Breath tests are commonly used to measure blood alcohol content (BAC) and determine if someone is over the legal limit for driving. These tests are quick and easy, but they aren’t always foolproof. In fact, several factors can lead to inaccurate results.
Device calibration and maintenance
Breath test devices need regular calibration and maintenance to give accurate readings. If the device isn’t properly maintained, it could show incorrect results. Calibration ensures the device measures BAC accurately, but an uncalibrated device might give either too high or too low a reading. It’s important for these devices to be regularly checked to ensure reliable performance.
Mouth alcohol
Another factor that can lead to inaccurate breath test results is the presence of mouth alcohol. Breath tests are meant to measure the alcohol in your deep lung air, not alcohol in your mouth. Things like using mouthwash, drinking alcohol right before the test, or even burping can cause residual alcohol to stay in the mouth. This residual alcohol can lead to a falsely high BAC reading that doesn’t reflect your actual blood alcohol level.
Medical conditions and diets
Certain medical conditions and diets can also impact breath test results. For example, people with acid reflux or GERD may have alcohol from their stomach pushed up into their throat, affecting the breath test. Additionally, those on a low-carb or ketogenic diet might have higher levels of acetone in their breath, which some breath test devices can mistake for alcohol, leading to inaccurate readings.
Environmental factors
Environmental factors, such as exposure to certain chemicals or substances, can also affect breath tests. Paint fumes, cleaning products, or even some breath sprays contain compounds that might interfere with the device’s ability to accurately read BAC. These external factors can contribute to false positives, especially if the person being tested has recently been around such substances.
Breath tests can be useful for estimating blood alcohol content, but they are not perfect. Many different issues can all affect their accuracy. It’s important to be aware of these limitations and understand that a breath test may not always provide a completely accurate result.