If you’re stopped by a police officer in Florida under suspicion of drunk driving, you may be presented with a choice of taking a field sobriety or breathalyzer test. Because many sobriety test readings are subjective and difficult for even sober individuals, many officers choose the breathalyzer.
How Do Breathalyzers Work?
Breathalyzers, or breath analyzers, are used to measure the amount of alcohol present on your breath. Any ethanol breathed into the device will, through chemical reaction, produce an electric current. The current level appears on display as a measure for ethanol presence.
Can Breathalyzers Be Wrong?
Not only can breathalyzers malfunction but they are also not as accurate at determining BAC as an actual blood test. According to scientific studies, when comparing breathalyzer estimates to actual BAC results taken from a blood sample, the margin of error is 50%. False results could stem from the following:
- Poor calibration: Handheld breathalyzers use a silicon oxide sensor, which can be contaminated by substances other than breath alcohol. They need to be calibrated or replaced every six months. An uncalibrated breathalyzer will produce inaccurate readings.
- Compounds interfering with the reading: Older breathalyzers can confuse the molecular structure of ethanol with other substances of a similar molecular structure or reactivity, such as acetone. This misidentification will produce a false positive.
- Overestimation of BAC: Certain breathalyzers assume the person being tested is of a particular body type, meaning the weight of alcohol to the volume of breath is standard for the reading. While most people fit that BAC category, some will show a higher amount of alcohol on their breath, which may not accord with the level of alcohol in their blood.