The Intoxilyzer 5000 uses infrared energy absorption of alcohol to measure the alcohol concentration of a breath sample.

Because different molecules absorb energy at different frequencies, and alcohol molecules absorb certain frequencies of infrared energy, the machine can measure how much alcohol is in the breath based on how much infrared energy is absorbed.

The Intoxilyzer 5000 instrument consists of a chamber. One end of this chamber is a quartz iodide lamp that emits infrared energy (directed through the chamber by a lens).  At the other end, another lens sends the energy leaving the chamber through rotating filters and onto an infrared energy detector. The filters only allow certain wavelengths through.

Initially, the instrument establishes a zero reference point by measuring the amount of infrared energy striking the detector when the sample chamber is filled with ambient air. During a breath test, as the amount of alcohol vapor in the chamber rises, the amount of infrared energy reaching the detector falls.

By finding the difference between the zero reference point and the breath test measurement, the instrument determines breath alcohol concentration. The unit displays the result in grams of alcohol per 210 liters.  To assure accurate test results, the Intoxilyzer 5000 breath analysis instrument also detects and compensates for acetone, which absorbs the same infrared frequencies as alcohol.

Inaccurate Breathalyzer Results: A Drunk Driving Defense

Unfortunately, there is a lot of debate about the accuracy and effectiveness of the Intoxilyzer 5000.

Opponents of the Intoxilyzer 5000 insist that the machine inaccurately measures other substances found in breath, giving inaccurately high breath alcohol content results.

Another problem with the Intoxilyzer 5000 is that the rate of breathing can affect the results.

If you have been crying or have hyperventilated due to the stress of being pulled over by the police or arrested, you may actually test artificially high.

Rose and Furton have determined:

“While the Intoxilyzer 5000 demonstrates good analytical precision for standard solutions it suffers from numerous sources of error including calibration solution errors, temperature variations and interfering endogenous volatile organic compounds.”

New Hampshire DWI Attorney, Ryan Russman is certified in Evidentiary Breath Alcohol Technician / Intoxilyzer Instrument giving him the experience to successfully defend his clients against a pending drunk-driving charge.

Russman Law: Drunk-driving defense related to a New Hampshire's breathalyzer test.