Breath alcohol tests, commonly known as breathalyzers, assess a person's blood alcohol content (BAC) by detecting ethanol in their breath. These tests offer a quick and straightforward method for determining recent alcohol consumption, making them a valuable tool for both law enforcement and employers. Electronic breathalyzers operate by using a mouthpiece and a sensor that detects the presence of alcohol. The device measures the resulting reaction and converts it into a numerical BAC value.

While breath alcohol tests may not be as detailed as hair or nail tests, they provide a rapid assessment of recent alcohol intake. Law enforcement often uses breathalyzers to identify impaired drivers, and employers may rely on them to ensure that employees remain alcohol-free during work hours.