Quote :

"I have yet to see you cite a single source in two page-long retorts, and you accuse me of not supporting claims? "

Nice attempt at legerdemain through Ad hominem, those with baseless claims generally do.

For starters, I'm not the one making quantitative claims that can't be verified in one direction or the other so I really have nothing that should require support. What I have done is post the fundamentals of the machine and how it operates. utilizing the minimum amounts of common sense, elementary scientific knowledge or google skills the information i presented can be verified, while yours cannot. I'll make it easier on you though.

http://science.howstuffworks.com/breathalyzer2.htm

remember when i said

Quote :

"The point is it measures whats in your lungs. It gets in your lungs through your blood and water particles in your blood aren't absorbed into your lungs the way that alcohol is absorbed[q/quote] well ... [quote]Alcohol­ is not digested upon absorption, nor chemically changed in the bloodstream. As the blood goes through the lungs, some of the alcohol moves across the membranes of the lung's air sacs (alveoli) into the air, because alcohol will evaporate from a solution -- that is, it is volatile"

Water isn't volatile, its not absorbed into your lungs the same.



remember when i said

Quote :

"even if they were the way the machine is set up is to bounce light off of alcohol particles specifically, so other ones are not supposed to be able to interfere with it."

well...

Quote :

"The filter wheel contains narrow band filters specific for the wavelengths of the bonds in ethanol."

Quote :

"The anecdote I provided was based on my personal experience, and the numbers I presented represented a measured difference under similar circumstances as being discussed"

let me explain to you why this is wrong. mostly because odds are that you had one roadside test and then another one at the station. the PBT they use on site isn't as accurate as the one at the station, which is why it isn't admissible in court. i've seen people have a .1 on a PBT and then blow under the legal limit a few moments later on an onsite intoxalyzer at a check point. not to mention the time that took place between the initial breath test and the first blow at a station. your anecdotal incident of correlation in no way indicates causation.

instead of further attempting to avoid addressing my questions by redirecting the same requests to me how about you address what has been said, or man up and admit your claims are flawed or "pulled out of your ass".

12/19/2008 5:03:58 PM

I am going to ignore your dick-beating, jargon-infested pedantry, and insinuations of superiority to focus on your argument and cited reference, if that's cool with you. It's indeed a discussion of the mechanics of a breathalyzer that, aside from clearly targetting the audience of school children, doesn't say a mother fucking thing that supports your claim.

I would be happy to demonstrate how to calculate the relative concentrations of chemicals in solution before and after mixing, if that's where you want to take this. If not, for arguments' sake, the Cliff Notes version is that diluting a solution reduces the concentration of the solute. Reducing the solution's concentration affects the alcohol vapor pressure, consequently the vapor concentration, and ultimately the calculated BAC. The time relationship of these events and extent of influence are both debatable. There are also the question of whether or not water consumption affects the enzyme activity in the liver positively or negatively, and which of the two factors of blood dilution and enzyme activity has greater influence. If you want to make a point, I suggest debating along these lines.

Incidentally, water is technically "volatile", as volatility is "in the context of chemistry, physics and thermodynamics a measure of the tendency of a substance to vaporize." It evaporates in the lung in much the same way as alcohol, and if you don't believe me or Wikipedia, exhale on cold glass for a reminder. The breathalyzer measures the absolute quantity, the mass if you will, of alcohol in your breath and then calculates the alcohol content by the ratio I mentioned earlier in the thread.

That said, please brush up on your "basic science", find some numbers, and come back with an argument... or please shut the fuck up, before I have to whipsmack you in the face with the straw man's bulging ad hominem.

[Edited on December 19, 2008 at 9:08 PM. Reason : .]

12/19/2008 8:40:09 PM

I found a source that makes an interesting observation about the relationship of water vapor to alcohol vapor:

Water, present in the form of vapor, in expired air will condense into the liquid form with a lowering of temperature. Air exhaled into the tubes of a breath test device, such as the Breathalyzer, is assumed to be saturated with water at about 93.2F . Decreases in this temperature can result in an underestimation of reported BAC due to condensation of water and the subsequent removal of alcohol from the expired air. One study showed that when the mouthpiece of the breath test instrument was kept at 23C, there was an average decrease in temperature of exhaled air by 1.6C.

and back on the original topic, it also provides many examples of challenges against the partition ratio*

http://www.forensic-evidence.com/site/Biol_Evid/Breath_Tests.html

[Edited on December 19, 2008 at 9:32 PM. Reason : *which I have deleted in lieu of providing the link]

12/19/2008 9:30:28 PM

Quote :

"It's indeed a discussion of the mechanics of a breathalyzer that, aside from clearly targetting the audience of school children, doesn't say a mother fucking thing that supports your claim."

The simplification of language with which information is explained does not invalidate the credibility of a source. It is written simply as to be able to reach a broad audience, but its clear now that not all who read the article cannot fully comprehend the information discussed.

How does that article not support even the most basic of my claims?

I stated that the breathalyzer doesn't read indiscriminately and that the machine is designed to filter out the other particles by utilizing wavelengths that specifically the bonds of alcohol absorb. As I recall there was a section, which i quoted above, that explicitly stated this point.

I also recall stating that the alcohol on your breath isn't exactly what was being measured on the machine and that it was instead calculating the alcohol particles that were emitted from your lungs since the lungs absorb alcohol through the blood. Once again, I recall a similar point being explicitly stated in the link provided.

I fail to accept your insinuation that my claims were not supported by the information I provided. If there is a point which I have not addressed please state clearly what it is instead of becoming continually more emotional and I will address it honestly and timely.

To further address your previous comments I still contend that induced vomiting or quick gulps of water would not reduce the measured blood alcohol concentration by 12 - 25% as you stated it would. The above points dictate the fundamentals of how the machine determines BAC through specific bonds and how the air measured is derived from blood through the lungs rather than "what is on your breath" as a means to refute your second to last post on page 1. I felt that this information would be sufficient in providing the basic knowledge so that one could further deduce that since the alcohol in the blood would have already saturated the lungs that drinking water or expelling contents from your stomach would be futile. My allowance for extension rather than being explicit about this point seems to rather have appeared as my not addressing the point.

As I failed, by my own admission, to explicitly address vomiting I will do so now. The small intestine is what accounts for 75% of alcohol absorption and (based on food intake) finds its way there quickly and absorbs alcohol at an accelerated rate when compared to the other organs which also absorb alcohol. Inducing vomiting as a means to empty stomach contents would have negligible impact on the breathalyzer results since only 20 - 25% of the alcohol absorbed is done so through the stomach and is absorbed at a much slower rate than that of other organs. What this means is that the additional stomach alcohol would not likely be absorbed in neither quantity nor rate to be sufficient in altering test results in the 12 - 25% range you suggested. Given these factors the emptying of the stomach would be moot. Moreover vomiting would bring the deep alveolar air (which has the highest alcohol concentration) further up which would render a breathalyzer test higher in reading and thus be counterproductive to one's cause.

Quote :

"the Cliff Notes version is that diluting a solution reduces the concentration of the solute."

this would be accurate if you were, say, mixing a drink and creating a solution with alcohol as a part. however, since the blood which has passed the lungs and saturated them with alcohol isn't mixed with the water ingested.

Quote :

"Incidentally, water is technically "volatile", as volatility is "in the context of chemistry, physics and thermodynamics a measure of the tendency of a substance to vaporize."

Sophistry. Alcohol is far more volatile than water is, a point which is hardly debatable.

Quote :

" I found a source that makes an interesting observation about the relationship of water vapor to alcohol vapor:"

Quote :

"Decreases in this temperature can result in an underestimation of reported BAC due to condensation of water and the subsequent removal of alcohol from the expired air."

I really don't see how this supports your point in any fashion, unless you're now suggesting that the these means which you've been championing succeed in their goal by lowering your body temperature.

If you would like to continue this discussion, I am more than happy to do so but believe it can be achieved through PM as this sort of discussion has no constructive contribution on the topic at hand.

12/22/2008 11:35:38 AM