4 factors that impact the accuracy of a breath test

Nov 1, 2016 | drunk driving

It’s important that every driver be fully engaged mentally and cognitively while driving. In America, someone is injured every two minutes in a drunk driving accident. This may mean that officers are on the lookout for those who are driving drunk. If a driver is pulled over by an officer who believes he or he was driving under the influence of alcohol or drugs, the driver may be given a breath test to determine if he or she is under or over the legal limit to be driving. While this may seem like a great way to get a quick answer about whether a driver is safe on the road, there are some factors that can impact the accuracy of a breath test that every driver should be aware of before being subjected to one.

1. Medical conditions


Some medical conditions like acid reflux, GERD or diabetes can affect a breath test. Diabetics have excess ketone levels which can falsely be identified as ethyl alcohol. Those with GERD or acid reflux may face a false positive when the testing device reads acid within the mouth rather than alcohol in the lungs.

2. Device calibration

Police officers are required to use special equipment to check blood alcohol levels when a driver is pulled over, but this is not enough. Officers are also required to recalibrate their devices after administering a test and keep detailed records regarding the device’s maintenance. If neither of these tasks are done correctly, the accuracy of the breath test may be affected.

3. Environmental factors


The presence of varnish, paint fumes and other chemicals like plastics and adhesives can cause a false positive on a breath test. If you are around any of these items before you are pulled over, there may be reason to question the results. Many drivers are exposed to these chemicals at work and may be unfairly accused if breath test results are inaccurate.

4. Medications

Some common over-the-counter medications can also cause a false positive on a breath test. Anbesol is commonly used for canker sores and may leave remnants of alcohol in the mouth. Some cough syrups contain a percentage of alcohol that can set off a breath test. Even cough drops and inhalers may have small traces of alcohol in them. It’s important to read the ingredients list on every medication if you are taking it before driving.

Know your limit

While many drivers are arrested each day for driving under the influence, the truth is that breath tests aren’t always 100 percent accurate. An attorney may be able to help you understand the different factors that can influence a breath test.