Drager Alcotest 7110 MKIII-C
Drager or Draeger (Drägerwerk in German) is a German company based in Lübeck which makes breathing and protection equipment, gas detection and analysis systems. The company is the manufacture of the Drager Alcotest 7110 MK III-C utilized by California law enforcement agencies making DUI arrests in Bay Area counties outside of San Francisco including, San Mateo, Alameda, Marin, Contra Costa, and Santa Clara.
The Drager Alcotest 7110 MKIII-C utilizes two different and independent systems for measuring blood alcohol level from a person's breath. The first system analyzes alcohol in breath samples through a technology called infrared spectroscopy (IR). The second system analyzes alcohol in the same breath sample utilizing electrochemical cell (EC) technology. The utilization of two technologies on the same breath sample (in essence, measuring the breath sample twice) is intended to provide a higher level of forensic and legal integrity than was capable on the Intoxilyzer 5000 which relies solely on infrared spectroscopy.
The above having been written, the manufacturer concedes, as it must, that it is not unusual to "observe slightly different results." However, the law enforcement agencies and their laboratories do not typically list the two results on the breath test card provided to the arrested person, their attorney or presented to the finder of fact in a DMV Hearing or at Trial. Rather, it is necessary for the attorney to request this information, which oftentimes isn't produced by the law enforcement agency's laboratory until the day of testimony.
In addition to the Alcotest 7110, Drager manufactures the Alcotest 9510 which has not yet been deployed by California law enforcement agencies making DUI arrests in the San Francisco Bay Area. Presently, these two machines are the only dual sensor breath alcohol testers manufactured. Each of these devices quantifies breath alcohol concentration by both the electro-chemical sensor and an infrared optical sensor operating at 9.5µm wave length.
Infrared Sensor
The Alcotest 7110 MKIII-C is designed to detect alcohol 9.5 µm reqion of the infrared spectrum. IR photometry is a significant advancement in IR breath analysis over the technology utilized by the Intoxilyzer 5000 which relied upon a chopper wheel with multiple optical filters. Drager represents that the technology utilized in the Alcotest 7110 MKIII-C has ended the search for better specificity for alcohol. 9.5 µm, contending technology is virtually non-sensitive to any potentially interfering substance in the breath of a subject.
Electrochemical Sensor
The electrochemical sensor of the Alcotest 7110 MKIII-C is mounted on the sample chamber of the infrared system. A small sample of the subject's breath is drawn from the 70 milliliter infrared sample chamber. Once a specific type of alcohol called ethanol (drinking alcohol) reaches the sensor, a chemical reaction is triggered. The resulting current is used to determine the amount of ethanol in the sample. Draeger contends that the heated and temperature controlled fuel cell is alcohol specific and non-susceptable to ambient alcohol vapor.
Drager's refusal to reveal source code for the Alcotest 7110 MK III-C was challenged by attorneys in Florida. The Florida Supreme Court state's supreme court has been reviewed by independent third parties and approved by a Supreme Court decision.