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CMI Intoxilyzer 5000 Breathalyzer

The manufacturer of the Intoxilyzer 5000 (CMI, Inc.) represents the device is "technologically advanced" in the introduction to the March, 2000 revision to the Operator's Manual. However, the Intoxilyzer 5000 has been replaced in most California counties by the Drager 7110 MK III C.

That having been written, San Francisco based California Highway Patrol Officers, San Francisco Police Officers, San Francisco Sheriff's Deputies, and National Park Service Police Officers continue to use the Intoxylizer 5000 as the evidential breath alcohol test in all of their DUI arrests.

As with all other breath alcohol testers, the Operator's Manual cautions officers that mouth alcohol can raise a "question of a test's validity." Additionally, the section of the manual entitled "Administering a Breath Test" explains that he mucous lining of the mouth cavity and nasal passages will store alcohol for some time after a person consumes alcohol. Further, the Operator's Manual explains, normal body processes eliminate residual mouth alcohol within 15 minutes.

For that reason, officers are instructed to observe a subject for at least 15 minutes before performing a test. During the observation time, the subject may not smoke, eat, drink or introduce any substance into his mouth. Furthermore, if the subject regurgitates, delay starting a breath test for at least 15 minutes from that time. Although the manual claims that the Intoxilyzer 5000 is "capable" of detecting mouth alcohol in a subject, the deprivation procedure should be closely observed to "avoid any question of a test's validity."

However, an invalid assumption must be made on any California breath test. Specifically, the assumption that ratio of breath to blood is 2100 to 1. In other words, the Intoxilyzer 5000 arbitrarily assumes an individual's breath to blood ratio of 2,100 parts breath to 1 part blood. From this the devices estimates Blood Alcohol Concentration. Additionally, other factors such as an individual's rte of metabolism, breathing, breath temperature, body temperature, and the presence of other chemical compounds called interferents can cause the Intoxilyzer 5000 to provide an inaccurately high report of a person's blood alcohol level.

The subject being tested for alcohol on the Intoxilyzer 5000 has three (3) minutes from the time the machine prompt to submit an adequate sample or a message indicating an insufficient sample will be printed onto the breath test card.

Checking Calibration of the Intoxilyzer 5000

The Operator's Manual represents the Intoxilyzer 5000 is permanently calibrated, but adds that periodic calibration checks may be required by an agency. An external alcohol simulator and a certified alcohol standard are required to check the instrument's calibration. The calibration of the Intoxilyzer 5000 may be checked using a wet bath simulator. Some Intoxilyzer 5000 instruments are also configured for calibration using a dry gas simulator.

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