DUI Articles

What are breathalyzers? A lot of people have heard of breathalyzers but aren't sure what are breathalyzers. In this DUI 101 article, we will introduce you to breathalyzers, how they work, and the different types of breathalyzers. What are breathalyzers?

Breathalyzer tests are commonly referenced in association with drunk driving and DUI laws. A breathalyzer is the device used to measure an individual's blood alcohol content (BAC), and gage their level of intoxication. In order to gain a reading, the subject must blow into the machine. Then, sensors within the unit measure the weight of alcohol to the volume of breath upon exhalation. However, the reading of a breathalyzer is actually only an estimate of BAC, due to the fact that a number of variables may affect the results. Therefore, breathalyzer tests are often given as a preliminary screening of BAC, and used in conjunction with field sobriety and blood tests.

Breathalyzers are not just for law enforcement anymore. They are being used by businesses and clinics to determine the sobriety of employees/patients in a fast and efficient manner, and by some schools that administer them in an effort to combat underage drinking and keep intoxicated individuals away from school parties and functions. In addition, a growing number of people are purchasing breathalyzers for personal use. Some individuals are giving them to loved ones out of concern for their safety. Plus, a number of college students use them regularly to determine if they themselves or their driver is under the legal BAC level for driving.

Several different types of breathalyzers exist, with varying degrees of accuracy. The ones used by law enforcement use platinum fuel sensors, and provide the most accurate readings. These breathalyzers that the police are using have come a long way since they debuted. While these are really accurate there are several different manufactures of them and the accuracy of them varies. Perhaps the best breathalyzers are made by Intoximeters. The hand held units that the public purchase use a silicone oxide sensor that is more prone to contamination and other interferences. However, pocket or purse sized instruments are far less expensive at around $50-$200, than professional grade breathalyzers that can cost up to $1500. In addition, automotive breathalyzers can be court issued or purchased for private use, in order to prevent drunk driving. These systems are sometimes referred to as ignition breathalyzers, because they function as an ignition interlock device that prevents the car from starting until the breath test has been passed.

As DUI 101 stated earlier breathalyzers are used to determine a BAC estimate only, due to the number of variables that may skew the data and produce false results. Research has determined that these instruments can produce results that vary as much as 15% from actual blood alcohol concentrations. Typically, breathalyzers are calibrated to measure BAC using the standard ratio of 2100:1. This ratio assumes the person being tested is average in terms of weight, height, and health. In addition, machines can be sensitive to temperature and other homeostatic variables.

A breath test is used to measure the alcohol volume in the air that is being pushed out of the lungs. Therefore, a falsely high reading may result if the machine senses alcohol that may have come from the mouth, throat, or stomach. For this reason, law enforcement is typically required to wait an allotted amount of time before having a driver blow into the instrument. Certain medical conditions such as acid reflux or periodontal disease may affect the accuracy of the test but shouldn't be relied on as an excuse if you fail a breathalyzer. Plus, mouth wash, breath spray, and asthma medications, have been known to produce abnormally high readings for a very slight time.