HOW BREATHING TECHNIQUES CAN INFLUENCE THE RESULTS OF BREATHALCOHOL ANALYSIS
The influence of breathing technique on the concentration of ethanol in breath and the temperature of end-expired breath was investigated. The experiments were performed with healthy men after they drank a moderate dose of ethanol, and the concentration of ethanol in breath was determined by gas chromatography. The results were compared with control breaths, which were deep inspirations and forced expirations of room air, analyzed within 2 to 3 minutes of the test breath sample. With breath holding (30 seconds) before expiration, the concentration of ethanol increased by 15,7 percent, and the temperature of breath rose by 0,6 degrees C. Hyperventilating for 20 seconds, immediately before the analysis of breath, decreased the concentrations of ethanol by 10,6 percent, and the breath temperature dropped by 1,0 degree C. Keeping the mouth closed for 5 minutes (shallow breathing) increased expired ethanol concentration by 7,3 percent, and the breath temperature rose by 0,7 degrees C. After a slow (20 seconds) exhalation, expired ethanol increased by 2,0 percent, but breath temperatures remained unchanged from control tests. Results suggest that the changes in expired ethanol concentrations are partly caused by the rise or fall in the temperature of breath. But an equally important factor is the amount of time that the breath spends in contact with the mucous membranes of the upper respiratory tract. A long contact time increases the concentration of ethanol, and rapid ventilation lowers it. Regardless of the breathing technique tested, the results recovered to control values immediately when the subjects began breathing normally again. (Author/TRRL)
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Corporate Authors:
Wright (John) and Sons, Limited
42-44 Triangle West
Bristol, England -
Authors:
- Jones, A W
- Conference:
- Publication Date: 1982
Media Info
- Pagination: p. 275-280
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Serial:
- Volume: 22
- Issue Number: 4
Subject/Index Terms
- TRT Terms: Accuracy; Alcohol breath tests; Alcohols; Blood alcohol levels; Breath; Concentration (Chemistry); Human factors; Methodology; Temperature
- Uncontrolled Terms: Quick
- Old TRIS Terms: Breathalyzers
- ITRD Terms: 7347: Alcohol; 1542: Alcohol test; 2082: Breath; 7132: Concentration (chem); 9102: Method; 9064: Quick; 6722: Temperature
- Subject Areas: Highways; Safety and Human Factors; I83: Accidents and the Human Factor;
Filing Info
- Accession Number: 00388905
- Record Type: Publication
- Source Agency: Transport Research Laboratory
- Files: ITRD, TRIS
- Created Date: Mar 29 1985 12:00AM