Published with permission from the book, DUI/DWI: The History of Driving Under the Influence, David N. Jolly. Outskirts Press (2009)
The DUI Guide: DUI Evidentiary Breath Test Devices
Verax Systems, Inc. originally manufactured the BAC Verifier but eventually sold the rights to the to National Patent Analytical Systems.
The BAC Verifier traps a larger breath sample than other breath analyzers which allows for duplicate analysis testing. It also allows for the trapping of a sufficient volume of air so that two separate samples of the same breath can be analyzed. As a result, two separate tests can be performed on the same breath sample.
Like other machines (the Intoxilyzer 5000, the Intoximeter 3000, and the Breathalyzer 2000) the BAC Verifier uses an infrared analysis and a microprocessor to minimize operator intervention and manipulation.
There are many potential sources of error in the BAC Verifier, which include problems with specificity and that the machine may be susceptible to radio-frequency interference (RFI). Interestingly, many breath testing machines were tested in late 1982 by NHTSA to determine susceptibility to RFI but the BAC Verifier was one of the machines not tested. The manufacturer claims that the machines have spray coating which shields them from any RFI but there is no independent testing to prove this.