Gokul43201
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Here... you decide.TheStatutoryApe said:In my case I was driving fine and passed a field sobriety test but was over the limit. Is BAC a measure of impairment?
Logan B K; Distefano S, "Ethanol content of various foods and soft drinks and their potential for interference with a breath-alcohol test", Journal of Analytical Toxicology 22 (1998).
Abstract:
A variety of breads and soft drinks were tested and found to contain low concentrations of alcohol. The potential for these products to generate false readings on an evidential breath-alcohol instrument was evaluated. Alcohol-free subjects ingested these products and then provided breath samples into a DataMaster. It was found that breath samples provided immediately after consumption of some of these products, or with them still present in the mouth, did produce low levels of apparent breath alcohol, which may or may not be rejected as invalid by the breath-test instrument. If the subject swallowed or expectorated the food or beverage and then observed a 15-min deprivation period during which nothing was introduced into the mouth, the apparent effect was eliminated. These findings emphasize the need for the mandatory pretest alcohol-deprivation period and the benefits of duplicate breath sampling.
How long after you left the bar before you took the breathalyzer test?
Did you ask to check the calibration of the meter? Did you take just one test or more than one? How many? Have you subsequently taken blood tests to establish you breath to blood partition ratio? Have you talked to a lawyer about any of this? My own opinion is that a 0.03% margin on a blood alcohol test by a single breathalyzer measurement is almost meaningless, but the law may be such that this margin is already accounted for in the legal limit.I'm just giving you the opinion of someone who's going through this for no other reason than .01% difference in a measurement.
Here's a paper on the systematic error bar on breath tests:
Gullberg Rod G; Logan Barry K "Results of a proposed breath alcohol proficiency test program" Journal of forensic sciences 51 (2006)
Abstract:
Although proficiency test programs have long been used in both clinical and forensic laboratories, they have not found uniform application in forensic breath alcohol programs. An initial effort to develop a proficiency test program appropriate to forensic breath alcohol analysis is described herein. A total of 11 jurisdictions participated in which 27 modern instruments were evaluated. Five wet bath simulator solutions with ethanol vapor concentrations ranging from 0.0254 to 0.2659 g/210 L were sent to participating programs, instructing them to perform n = 10 measurements on each solution using the same instrument. Four of the solutions contained ethanol only and one contained ethanol mixed with acetone. The systematic errors for all instruments ranged from -11.3% to +11.4% while the coefficient of variations ranged from zero to 6.1%. A components-of-variance analysis revealed at least 79% of the total variance as being due to the between-instrument component for all concentrations. Improving proficiency test program development should consider: (1) clear protocol instructions, (2) frequency of proficiency testing, (3) use lower concentrations for determining limits-of-detection and -quantitation, etc. Despite the lack of a biological component, proficiency test participation should enhance the credibility of forensic breath test programs.
And if you measured 0.01% over in a measurement of 0.09%, that's 11.1% over the legal limit. A second measurement or a different instrument may just as easily have read 0.08%.
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