Both in Maryland and across the United States, breath alcohol testing is a crucial step for police to determine if a suspect is driving under the influence (DUI) of alcohol. While breath testing is not the only test available, it is commonly used in DUI pullovers and can play a large part in both arrests and trials. With so much placed on the results of a breath test, it is important to understand how these machines work.
Most breath tests, commonly referred to as breathalyzers, are small handheld devices that look like a box with a tube sticking out of it. There are also larger versions of the machines, but the small versions are practical for police out on patrol. When a subject is administered a breathalyzer test, he or she must expel as much air as he or she possibly can so the breathalyzer can measure the deep air in the lungs and produce an accurate result. Anything other than this may result in an incorrect result.
Breath tests measure BAC through the amount of alcohol molecules in a subject’s breath, but there are several ways this can be done in the machine. Breath tests can measure alcohol through:
- Chemical reaction with alcohol that results in a color change alerting police to the presence of alcohol; the greater the color change, the greater the amount of alcohol.
- Infrared light that is absorbed into the molecules of the breath; an electrical reaction occurs that measures only the alcohol molecules and produces a reading of the BAC.
- Fuel cell chemical reaction that uses the alcohol in a subject’s breath to interact with a fuel cell in the breath test. The alcohol molecules will react to create an electrical current which will show how much breath alcohol content is present.
Not all breath tests are accurate, however. Incorrect calibration, administration, or reading of the test can result in a false arrest. If you have been charged with a DUI in Maryland, the Waldorf drunk driving defense attorneys at Alpert Schreyer can fight to have your charges reduced or even dismissed completely. Contact us today at (866) 444-6363 for a consultation on your case.