Tag Archives: breath testing

Infrared Spectroscopy and the Falsely High Breath Test (by DaytonDUI)

The Intoxilyzer 8000 operates using the scientific principle of infrared (IR) spectroscopy, which identifies molecules based on the way they absorb infrared (IR) light.  More specifically, when molecules in a breath sample are exposed to IR light the way they vibrate changes due to the bending of the (C-O, O-H, C-H, C-C) bonds.  Each type…
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Ohio DUI Law: The Hematocrit Defense

How bloody is your blood?  The hematocrit is the number expressing the cell volume of blood (the size and number of red blood cells in proportion to the rest of the blood).  As humans, we all have a natural variation in our hematocrit.  Healthy men have a natural variance from 40.7% to 50% and healthy…
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DUI Science and More Faulty Breath Machine Assumptions

Evidential Breath Testing Measures The Amount of Alcohol In Your Breath Not in Your Brain! One of the faulty assumptions underlying evidential breath testing is the assumption that the tests are measuring the ability of alcohol to impair your brain.  They do not.  The breath test does not care how, or even if, the alcohol…
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Residual Mouth Alcohol, Slope Detectors and the 20 Minute Observation

One of the most prevalent causes of error in breath-alcohol analysis is the presence of alcohol in the mouth.  This residual mouth alcohol (hereinafter R.M.A.) contaminates the expired breath captured by the machine and elevates the test results radically.  The BAC Datamaster’s computer is programmed to assume that a breath test reading is 100% deep-lung…
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Dayton DUI Law: The GERD Defense

Regurgitation and Reflux are not the same thing!  Reflux is the movement of ethanol vapor back up the esophagus from the stomach which has the ability to contaminate a breath sample.  The defendant who suffers from Gastroesophageal Reflux Disease (GERD) will not exhibit outward signs of distress or other signs which a breath testing technician…
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