The Oklahoma Breath Test Machine

The state of Oklahoma uses the Intoxilyzer 8000 to conduct breath tests for BAC. This machine is also referred to as the “breathalyzer.” The 8000 has been around over 10 years and new and improved models, such as the Intoxilyzer 9000, have been released. However, Oklahoma does not use the latest model 9000 but still relies upon the older 8000 models.

Essentially, the Intoxilyzer 8000 is a computer that is based on very old technology. It utilizes a Z-80 microprocessor, which was introduced in 1975—over 30 years ago. This is the same microprocessor that was used in the very first home computers in the early 1980s.

The machine works on the theory of infrared absorption. Basically, a light bulb is positioned at one end of a breath capture cylinder. When a person blows into the machine, the breath enters this chamber and light from the bulb shines through the breath. Filter wheels at the other end of the chamber begin spinning, while the infrared light causes any alcohol molecules to absorb light at a particular frequency. The machine then makes a mathematical conversion, which is displayed as a “blood alcohol content” percentage on the machine’s display.

How reliable is the breathalyzer?

While this all sounds very technical and advanced, opponents argue that the machine is inherently flawed and often produces readings that are falsely high. It has been argued that the Intoxilyzer8000 can misread other substances in the breath as alcohol, thereby giving an inaccurate BAC reading.

This machine works on an assumption that everyone has a blood/breath ratio of 2100/1—that is, 2100 parts of alcohol in the breath for every one part of alcohol in the blood. A person with a higher blood/breath ratio will not be adversely affected by this assumption; however, someone with a naturally lower blood/breath ratio will produce a reading higher than their actual BAC. There are documented cases of people with blood/breath ratios as low as 1100/1.

It is worth noting that Oklahoma law only requires the Intoxilyzer8000 to perform within a plus or minus 10% accuracy rate.

The takeaway is, if you are arrested for DUI, submit to a breathalyzer test and blow a .08% or higher, you will face DUI charges—even if your true BAC was less than the machine indicated.

The Hunsucker Legal Group

If you have been charged with DUI in Oklahoma, call the Hunsucker Legal Group today. Our attorneys are experienced in defending erroneous breathalyzer readings, and we are ready to help you obtain the best possible outcome in your case.

Call the Hunsucker Legal Group at 405-231-5600 to schedule a free, no-obligation case consultation.