I gave 2 breath samples into the machine, which one is considered my actual BAC by the state?
All breath tests require the subject to give 2 samples. Of those 2 samples, the lower of the 2 samples is considered to be your BAC for purposes of your DUI. For example if you blew a .080 and a .074 then the .074 will be used by the state. Again, if you blew a .194 and a .182 then the .182 will be your BAC.
I gave one breath sample, and then refused to give another. What does this mean?
In this scenario the one breath sample you did give will be used as your BAC. You will not be charged as having refused the test because you did give one sample.
Will recent use of mouthwash or other substances skew my results on the Intoxilyzer 5000 or Intoxilyzer 9000?
The Intoxilyzer 5000 and Intoxilyzer 9000 Operators will tell you that mouth alcohol will not be detected by the machines, but this is simply not true. Many experiments have shown that the Intoxilyzer 5000 and Intoxilyzer 9000 will detect and register mouth alcohol. When I went through Intoxilyzer 5000 training, our instructor said the machine would not register his use of mouthwash. He then took a swig of Scope, swished it around, spit it out, and blew in the machine. Instead of the machine discounting the mouth alcohol and reading .000 the machine detected the Scope and registered .280.
Aside from mouthwash, mouth alcohol can interfere with the results of the Intoxilyzer 5000 or Intoxilyzer 9000 in other ways. If a subject burps, vomits, etc. within a 20 minute period before being tested on the machine, any alcohol left in the mouth from the belch or vomiting may skew the subject's test results upward. Just as in the Scope example above, the machine is not supposed to detect this mouth alcohol, but there is often a huge gap between what the machine does in theory and how it performs in reality.
Is it true sucking on pennies will help me beat an Intoxilyzer 5000, Intoxilyzer 9000, or Breathalyzer?
No, this is not true. Lots of people have heard this urban legend, and all that will happen is the officer will book the pennies into evidence, and the jury will hear what you were doing. The rumor behind this legend is that the machines read electrical current inside your mouth to help determine your BAC level. The copper from the pennies is supposed to absorb this electricity so the machine won't have anything to detect. Both the legend, and the way the machine works in these stories is false.
I had a fever when I took my breath test. Could this have affected my results?
Yes. A 1 degree change in body temperature can affect the breath result by an average of 6 to 7%. A person who is running a fever that is 2 degrees high could have a result that is off by 12 to 14%. In California, for instance, the state's breath machine records each subject's body temperature at the time of testing. In Georgia, the Intoxilyzer 5000 and Intoxilyzer 9000 do not. The Intoxilyzer 5000 and Intoxilyzer 9000 assume a constant body temperature for all subjects at 98.6 degrees.
How does a breath machine tell how much alcohol is in my blood?
The Intoxilyzer 5000 and Intoxilyzer 9000 operate on the principle of Henry's Law. Henry's Law states that the concentration of a material in a gas state above a liquid containing the dissolved material will be proportional to the concentration of the material in the liquid state. More plainly stated, the gas above a liquid will have the same concentration of a substance in it as the liquid beneath the gas.
How does this apply to you and your BAC? If you've been drinking, alcohol vapors (the gas) will come into contact with your blood (liquid) in your lungs. While in the lung, the alcohol diffuses across the one cell thick semi-permeable membrane of the capillaries into the air of the lung. The higher the concentration of alcohol in a subject's blood, the greater the proportional concentration of alcohol in the air in the lung. When a subject breathes this air into the Intoxilyzer 5000 or Intoxilyzer 9000 it measures this concentration.
In order for the Intoxilyzer 5000 or Intoxilyzer 9000 to be able to apply Henry's Law to breath testing, the machine has to assume many constants about the human body. For instance, the Intoxilyzer 5000 and Intoxilyzer 9000 assume a 2,100 to 1 ratio in converting alcohol in the breath to estimates of alcohol in the blood. However, this ratio varies from person to person with a range of 1,900 to 2,400. This number not only varies among people, but also varies in an individual over time. Some breath machines assume a hematocrit of 47%. However, the hematocrit level in men ranges from 42 to 49% and ranges 37 to 47% in women. The Intoxilyzer 5000 and Intoxilyzer 9000 also assume an average body temperature of 98.6 degrees (see question above). As we all know, not every person is the same. Having a breath machines that assume all men, women, and people in general are all the same is discriminatory.
Which test is better, breath or blood?
A blood test is generally thought to be more accurate. Officers almost always ask for a breath test because it is more convenient for them. However, if you submitted to a state administered blood test there is a good chance your numbers have been skewed or compromised. The best blood tests come from independent labs that test the actual blood, with properly calibrated equipment, and properly stored specimens.