California DUI

Blood Alcohol Testing Machines

Two interesting observations can be made about the Datamaster. First, the changes required by Washington State clearly indicate rather significant deficiencies in the existing Verifier used in other parts of the country. Second, the Datamaster itself has encountered problems: Eight of the first machines received had to be returned because they failed to meet specifications; twenty-five have had to be repaired because of a variety of problems. Common problems included inaccurate readings because of meter valve instability, failure to detect the presence of acetaldehyde and false readings caused by infrared lamp instability.

The Verifier/Datamaster has a number of components that are very sensitive to temperature change..

  1. The simulator solution, as with any breath machine, must be kept at 34 degrees centigrade, plus or minus .02; a decrease of one degree will cause a 6.8 percent decrease in the amount of alcohol, resulting in a falsely higher BAC reading for tested breath samples. A thermometer attached to the simulator is supposed to be checked by the operator.
  2. The sample chamber must be heated to exactly 50 degrees; this is supposedly monitored by the machine's computer.
  3. The detector must be cooled almost to freezing; this is also theoretically monitored by the computer.
  4. The breath tube must be heated to 50 degrees. If not properly heated, condensation can form in the tube; this can capture alcohol during a test, which will be picked up by later breath samples. Despite the need for a 50 degree temperature, the Operator's Manual tells the operator only to "check that the mouth piece is warm to the touch."

It is also of interest that the Verifier/Datamaster's Service Guide lists the following possible error messages on the LCD display. Note, incidentally, that there is nothing to indicate that the computer is malfunctioning, such as by not detecting and reporting the following malfunctions.

  • Temperature Low
  • Temperature High
  • Printer Error
  • CRC Error
  • Pump Error
  • System Won't Zero

This last entry is followed by the notation that, "It is possible that there may be physical blockages of the IR (infrared) energy along the path from Source to Detector..... Possible causes of blockage:

  • Simulator solution in sample chamber. This can occur if the simulator is hooked up to the instrument incorrectly.
  • Cracked windows or mirrors.
  • Chopper wheel not turning.
  • Condensation or fog building up on windows or mirrors due to leakage in the system.
  • Any other foreign material in sample chamber.

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California DUI