According to DOT guidelines, alcohol testing may only be performed by qualified screening test or breath alcohol technicians, and must take place at testing sites that meet U.S. government standards.
An employee blows into the mouthpiece of an evidential breath testing device, that measures breath alcohol concentrations, for a minimum of six seconds. If the device measures a concentration of less than 0.02, the employee passes the test.
When the original test registers an alcohol concentration over 0.02, the employee is required to take a confirmation test. The follow-up exam must be administered between15 and 30 minutes after the initial test. Failure to pass the second test may result in termination of employment.
The U.S. Department of Transportation allows the use of saliva-testing devices, which measure alcohol concentrations through insertion into a subject's mouth; however, such tests are restricted from all confirmation-test procedures.
