Alcohol TestingBreath or Blood Alcohol Testing
The two most common methods of testing for alcohol include procedures which involve sampling blood or breath. If you look at the science behind the testing, both have very good reliability and research has documented direct correlation between alcohol concentration in the blood or breath and the level of impairment.

The breakdown of alcohol within the blood is determined by enzyme action. The amount of enzyme and it's activity can be affected by things such as gender, smoking status and use of certain medications. Lawyers who handle cases involving positive alcohol testing will use this knowledge to interpret the results differently.

DOT testing is done using a sample of breath. The reasoning behind this choice largely involves control of the sample and testing environment. Taking a sample of breath is much less invasive than blood. The phlebotomy (blood draw) procedure can be uncomfortable for the donor. Complications can occur with phlebotomy leading to injury to a nerve or other tissues and there would be higher risk of possible expose to a possible blood borne pathogen if done improperly.

When breath sampled according to DOT or State regulations it involves doing a split test. If an individual completes a test and is positive then a second test is done within the next 20 minutes to confirm the presence and level of alcohol. After each positive, the certified equipment must also be calibrated to ensure that the results are accurate. The results are known immediately and the company is able to react immediately on the results to address the problem. DOT and the State regulations also have guidelines that determine the consequences on work activity and rehabilitation based on the positive results.

A blood test requires that only one sample is taken. In a random situation, the donor would then resume work and await the results which could be delayed. Most laboratories can complete alcohol levels. The issues that may present in a legal situation dealing with blood testing would include the laboratories certification, calibration of the equipment and chain of custody procedures.

At this time we recommend employers use breath sampling for scheduled testing situations and use blood only if it is impossible for the donor to provide a breath sample, i.e. unconscious from an injury. The DOT regulations provide an excellent defensible model for a policy for substance abuse testing irrelevant of whether the testing falls within it's confines.

Please see the Workplace/On-Site Drug Testing tab for current Alcohol testing fees and availability or you can call (205) 823-9648 or e-mail us at to discuss you specific situation and needs.