The following excerpt about breath testing is taken from a portion of Chapter 5 from The Georgia DUI Defense Trial Practice Manual, © 1996 William C. Head. The reader should understand that the material provided is in no way comprehensive, but outlines certain legal attacks on breath testing. Historically, many breath tests (and some refusals) have been excluded prior to trial on other grounds other than the ones mentioned in the excerpt.

5.1.2. The Intoxilyzer 5000

The manufacturer of the "Intoxilyzer" line of breath screening and evidential devices is CMI, a Kentucky corporation based in Owensboro, Kentucky. The breath testing device was originally developed by Richard A. Harte of Omicron Systems Corporation of Palo Alto, CA, and was originally called the "Omicron Intoxilyzer."

Varying models of the "Intoxilyzer" are in use by more than 35 states, and nearly 30 states have it as their sole breath testing device. It is the most widely used breath testing device in America, although there are numerous versions or models in use: Models 4011, 4011A, 4011AS, 4011AS-A, and the 5000. There are various "series" of the 5000, including the 568G, used by Oregon, the 564, used by Alabama, the 568 series used by Florida and the series 768GA used by Georgia.

The machine formerly used by Georgia was the Intoximeter 3000, Model B-2A. The Intoximeter 3000 is no longer being manufactured by Intoximeters, Inc. The company is now marketing a new machine called the Intoximeter EC-IR.

The Intoximeter 3000 was the first infrared machine with computer capabilities. However, after the GBI removed or disengaged the Taguchi cells in the machine in 1984 [See Lattarulo v. State, 261 Ga. 124, 401 S.E.2d 516 (1991)], the 3000 (as used in Georgia) had lost its capability to distinguish between alcohol and other volatile chemicals having similar infrared "fingerprints." Without the Taguchi cell, the instrument was simply a single wavelength infrared tester, which was totally NON-SPECIFIC for ethanol (alcohol). Hence, it was used to convict many persons who had unknown concentrations of alcohol on their breath, but which could very well have been "mixed" with toluene, acetone, benzene, methyl ethyl ketone or an array of other "like" substances. See Oxley v. State, 210 Ga. App. 296, 435 S.E.2d 705 (1993).

Earlier models of the 5000 had a three filter design which identified only acetone, other than detecting ethanol. The acetaldehyde detector was offered as an option by CMI using the three filter design. Other chemicals could not reliably be detected or reported. The three-filter machine was similar to an Intoximeter 3000 with a working Taguchi cell, except that the Intoxilyzer 5000 checked for the presence of ethyl alcohol at two wavelengths. The request for a more "sophisticated" machine led to development by CMI of the machine (the Intoxilyzer 5000, Series 768GA) purchased by Georgia and other states. This machine has five filters which center on 3.80, 3.40, 3.47, 3.52 and 3.36 microns of the infrared spectrum. These are designed to detect ethyl alcohol (2 bands), acetone, acetaldehyde and toluene.