If you are pulled over in Oregon and arrested for suspicion of DUII, you will likely be taken to a police station to test your blood alcohol content (BAC). You’ve likely heard of a “breath test” and a “blood test” as methods for testing a person’s BAC, but what’s the difference between the two?

Breath Test vs. Blood Test

There are a few differences between these two tests. The most obvious difference is the process of the test. For a breathalyzer, you simply blow a couple of breath samples into a hand-held mouthpiece attached to a machine. A blood test is done by taking a blood sample, which is then sent to a separate lab to be analyzed. Because of Oregon’s implied consent law, you are expected to comply by providing a breath test willingly – if you refuse you may face a longer suspension and a separate violation for refusal. If you refuse a breath test, the officer can apply for a search warrant to obtain a blood draw from you. Additionally, if there was an accident and you are taken to the hospital a breath test is not an option, so an investigating officer might request a blood draw.

Breath Test

A breathalyzer test is performed at the police station on an Intoxilyzer machine. You are asked to blow into a tube that is attached to a machine two separate times. The machine analyzes your breath samples to test for alcohol molecules and produces a reading of your estimated BAC.

Blood Test

A blood test involves submitting a blood draw. Most commonly the blood is drawn at the police station by a mobile blood draw technician. A blood test may also be performed at a hospital by a phlebotomist if you are hospitalized for medical treatment after an alleged DUI incident. Once your sample is drawn, it will be given to the officer and taken back to the police station to be transported to the crime lab for analysis. 

Breathalyzer vs. Blood Test Accuracy

The chemistry of how a breathalyzer works is sophisticated and complex. It involves measuring the oxidation of the alcohol in your breath. The alcohol in your breath can be indicative of the alcohol in your blood because the alcohol dissolved in your blood is proportionate to the alcohol in your breath.

Breath tests have a larger margin for error because they can be skewed by diet, health issues, mouthwash, mints, or other products that contain alcohol. Blood tests generally produce more accurate results than breathalyzers because blood tests are less impacted by external factors. However, blood and breath tests typically produce very close results, being only marginally different.

Why do police use breath tests if they can be skewed?

Breath tests are less invasive than blood tests and easier to administer. They also produce results immediately rather than waiting for laboratory results. And today, breathalyzers are very accurate if they are maintained, calibrated, and used according to the procedure.

Contact Reynolds Defense Firm

If you or someone you care about is facing a DUI charge in Oregon, call Reynolds Defense Firm today.  We have a team of DUI attorneys with over 100 years of combined experience who are here to help. Our firm believes everyone who calls deserves a free consultation, so please do not hesitate to contact us.  The Reynolds Defense Firm team is happy to answer all of your questions and will point you in the right direction so you can sleep better at night.