Oregon DUII Frequently Asked Questions
Oregon Driver's License Suspensions
Oregon DUII Collateral Consequences
Oregon Intoxilyzer 8000
For several years, Oregon used the Intoxilyzer 5000. In the Fall of 2006, the Oregon State Police began installing new Intoxilyzer 8000 units around the state and the use of the Intoxilyzer 5000 was discontinued completely in Oregon. Both the Intoxilyzer 5000 and the Intoxilyzer 8000 are made in Kentucky by CMI, Inc. CMI will not sell or lease it's products to any independent scientific labs for testing and CMI will not disclose how the machine works by allowing the computer source code (used to program the machine and to tell the machine how to function) to be revealed or analyzed by independent scientists and computer programmers.
The new Intoxilyzer 8000 has many differences from the older Intoxilyzer 5000, but the principles upon which the device purports to gauge a driver's blood alcohol content are very similar. The Intoxilyzer 8000 uses the principle of infrared light absorption to attempt to estimate the present of alcohol in a gas sample. In theory, the Intoxilyzer 8000 is supposed to be able to estimate blood alcohol level from breath alcohol level by extrapolating using a presumed ratio (often referred to as a partition ratio). Despite the fact that the partition ratio varies from person to person, the Intoxilyzer 8000 makes an assumption that the ratio is the same for everyone and that it's 2,100:1. This means that the Intoxilyzer 8000 assumes that for every molecule of alcohol in your breath, that there are 2,100 molecules in your blood stream. If, because of body size, lung capacity, ethnicity, or other factors, your partition ratio is higher or lower than the Intoxilyzer 8000 assumes it is, your test result will vary wildly and could result in a false reading about the .08 standard.
The Intoxilyzer 8000 is also prone to errors due to mouth alcohol and interferants. While the Intoxilyzer 8000 is supposed to be able to distinguish other interferants (such as solvents or volatile organic compounds) from alcohol, it cannot if the molecules are similar in shape to those of alcohol. People who work around paints and solvents, for example, will often have false readings when they blow into an Intoxilyzer 8000. Similarly, the manufacturer of the Intoxilyzer 8000 states that the machine has a slope detector in order to detect mouth alcohol which might provide a false reading, but the slope detector does not work all the time. Mouth alcohol could be present for someone who was recently drinking or who burped, vomited, or regurgitated prior to providing a breath sample. To be clear, I have witnessed the slope detector function as designed and report mouth alcohol for someone who had not been drinking, but had swished mouthwash just before the test. However, I have personally witnessed on more than one machine, people who had been drinking (although who were not intoxicated and not over a .08, blow readings in the .20-.30 range and the machines had no idea the result was from pure mouth alcohol (the test participants had swished with either mouthwash or had alcohol to simulate recent drinking or belching).
To provide a breath sample into the Intoxilyzer 8000, you must blow long and strong into the mouthpiece attached to the machine. You must then wait, and provide a second sample. The machine will only print a reading if you complete both portions of the test (two full blows). Another factor that can cause the machine to provide an inaccurate reading is the sample volume. The Intoxilyzer 8000 only requires 1.1 liters of breath to produce a reading, but many people provide samples larger than this. Scientists knowledgeable about breath testing will tell you that the longer you blow, the higher you go. This means that, when the arresting officer tells you to keep blowing longer and harder, he is not likely doing this to help you. Your attorney can request COBRA data from the Intoxilyzer 8000 so you can see for yourself that longer blow times and larger samples usually result in a higher breath alcohol estimate.
There are many other reasons that breath testing, and the Intoxilyzer 8000, should not be trusted. Speak with your attorney about the machine before you assume that a high reading means that you, or someone that you car about, was "drunk." A breath test reading is an estimate only and can be effected by all of the following factors (some of which were mentioned above):
- Breathing Pattern
- Breath Temperature
- Male vs. Female Test Subject
- Ethnicity
- Lung Capacity
- Partition Ratio
- Outdated Software
- Source Code Errors
- Individual Machine Variance/Variaiblity
- Problematic/Defective Machine
- Inadequate Machine Maintenance
- Inadequate Maintainance Records
- Radio Frequency Interference (RFI)
The decision of whether or not to provide a breath sample is complicated. There are both administrative and quasi-criminal (i.e. violation) penalties for refusing to submit to the breath test. However, the Intoxilyzer 8000 is not always accurate and a false high reading can result in a greater possibility that you'll be convicted of the crime of DUII. If you refuse, there is a very strong likelihood that the arresting officer will obtain a search warrant to take a blood sample from you for testing. For better or for worse, blood testing is more accurate than breath testing.
If you are reading this page, you are not likely sitting in the local jail or at a police station making the decision of whether or not to provide a breath sample. You probably either already provided a breath sample, or you refused. In any event, you should speak with an attorney about your options regarding your breath test or refusal. You should not assume that any breath test result over .08 means that you will be convicted of DUII or that you will lose your driving privileges. Similarly, you should not assume that the local District Attorney's office will not charge you with DUII if you blew a .07 or even a .05.
Romano Law, P.C. and Michael G. Romano are licensed to practice in the state of Oregon only. The information provided on this website is offered for informational purposes only. It is not offered as legal advice and does not constitute legal advice. Romano Law, P.C. does not seek to represent you based upon your visit to or review of this website. This website may be considered advertising under the rules of the Oregon Bar Association. You should not make legal decisions based upon brochures, advertising, or other promotional materials. If you would like to schedule a consultation to discuss a specific legal matter, please contact our offices.