The most commonly used approved instrument in Ontario is the Intoxilyzer® 8000C. The software versions used in Ontario are 8167.08.00, 8167.12.00, and 8167.13.00.

Front of Intoxilyzer 8000C

According to the Intoxilyzer® 8000C Training Aid of 2013 (page 22 of 238) published by the Centre of Forensic Sciences in Toronto:


"The Intoxilyzer® 8000C is an automated, infrared-based evidentiary breath alcohol testing instrument manufactured by CMI Inc. of Owensboro,


And at page 33 of 238:


"The Intoxilyzer® 8000C provides information to the Qualified Technician via
the digital screen display. In addition to the digital display, the instrument
communicates by three different audible tones."


And at page 42 of 238:


"The instrument pulses IR light through the sample chamber with a frequency
of 2 Hz (2 pulses/second)."

"Because there are two detectors, which independently analyze the monitored
wavelengths (3.4 μm and 9.4 μm), there are actually 4 analyses per second."

"Therefore, a breath sample in the sample chamber is analyzed every 250 ms."


The two wavelengths analyzed 2 times each per second, on the 8000C, compare with the Intoxilyzer 5000C which analyzes each of three wavelengths 30 times per second. The following is taken from the RCMP 5000C Intoxilyzer Resources Manual page 6-5:


"The filter wheel is driven by an electric motor so that it spins constantly at about 1800
revolutions per minute (rpm). What this does, in effect, is place the three filters, one after the other in quick succession, in the beam of radiation emerging from the sample chamber. At 1800 rpm, each filter will be in the beam 30 times per second. As each filter moves into the beam, it transmits a burst of radiation at its own characteristic wavelength, and blocks all others. So, if we think of the beam of radiation that then travels from the filter wheel to the detector, we can visualize a repeating series of pulses, each
corresponding to one of the three wavelengths ..."


The 5000C has a steel case. The 8000C has a plastic case with copper-coloured paint inside. Which instrument do you think is more impervious to radio frequency interference? Perhaps defence lawyers and experts in private practice need to test the following hypothesis experimentally by placing a cell phone inside the case of an 8000C and then sending a text or making a phone call to that cell phone. If you take one of my hands-on courses at my office you'll find out experimentally. Note page 140 of 238 of the 2013 CFS 8000C Training Aid:


"Note that while the instrument is sensitive to the detection of RFI; it is
unaffected by its presence. The design of the instrument provides a coating
throughout the interior of the instrument which protects against RFI signals
entering the instrument. Most importantly, the detector is housed in a metal
shield at the end of the sample chamber that is impervious to RFI."

Click here to visit my YouTube Channel with 20 videos of experiments with RFI effects on evidentiary breath testing instruments.

Below please see interior images of one of our office 8000s:

1. Copper paint on the inside of the plastic 8000 box.

2. Aluminum housing at the end of the sample chamber into which the "metal shield" and detector fits with 3 screws.

3. The "metal shield" around the detector which is really just a copper washer.

Interior of Intoxilyzer 8000
End of sample chamber on Intoxilyzer 8000
Signal detector at end of Intoxilyzer 8000 sample chamber

Defence counsel need to be familiar with the basic features and the limitations of the approved instruments used by their local police.


The video below will tell you more about the 8000C breath test sequences course at at You can learn more about courses by visiting the "Members" section of this site.

Please also visit our DUI BAC Instruments Database.

If you are interested in the subject of measurement science for a forensic purpose, generally, or approved breath instrument measurement science, specifically, we recommend a visit to:

See also the Naked Intoxilyzer 8000C page