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What Is The Portable Breath Test And How Reliable Is It?


This would be less reliable than the evidential test, depending on which machine they used. Officers in California use the older machine, the Alco-Sensor IV. They are reliable to a certain level, and more often than not they are accurate, but they do not have a slope detector which could detect mouth alcohol, recent drinking or alcohol that was trapped in the teeth. If the person had recently used mouthwash or they were eating soya sauce and there was rice or food particles holding in the soya sauce or other alcohol they had drunk, then that might show as alcohol on the breath and it might look like alcohol because we would not know whether it was coming from the mouth or from the deep lung alveolar sacs from where they were supposed to be getting a sample. A microscopic amount of alcohol in the mouth can make someone who has under a 0.08 BAC, show more than a 0.08 on these machines. This is why it is only used as another field test in determining whether or not to arrest someone for a DUI, and then the official chemical test would be given which would be supposed to be more accurate. This would be a preliminary test and it is a test for which most officers now have these machines in their cars and they use them to help determine whether or not to make an arrest for a DUI. They usually use the breathalyzer as the last field sobriety test after the standardized tests if they give those, and any other tests such as counting fingers or having the person touch their nose or head back, eyes closed, estimate 30 seconds, the Romberg test or other tests that officers may give.

Do People Get The Portable Breath Test Confused With The One At The Police Station?

Absolutely, and this happens because a lot of officers do not properly explain what is going on. We can assume that people would not be confused if the officer explained that a test was just another field sobriety test to help determine whether or not they should let the person drive home or arrest them for DUI, because in case they were arrested for a DUI, they would be required to do a blood or breath test after the arrest. People in whatever state of mind they are in after they have been pulled over, may still be confused and that might have to do with panicking, fear, stress, alcohol level or any other reason. A lot of people have a lot of anxiety, they may be on a lot of different medications or they just might not necessarily be following what the officer was saying or maybe it was not said clearly. Sometimes officers do not do the best job to make it very clear, although I have heard some officers do fantastic work and they are patient and explain things to people, whereas other times I have seen officers turn the sobriety tests into a complete joke by turning the person’s fear or questions into a refusal to take a chemical test due to the officer’s impatience, resulting in that person potentially losing their license for a year.

How Important Is That Observation Period?

The observation period is extremely important because if the person did burp or regurgitate, then that would mean the alcohol in their stomach could come up into their throat, into their mouth and mouth alcohol might be present which would mean an invalid sample because that would not be a sample that was coming from the deep lung area, the alveolar sacs, where the breath would need to be taken from. Once fully absorbed, the body would give a true or close to true blood alcohol level from a deep lung sample or from a blood test. The breath test would do a conversion to convert it from breath to blood, which because of conversion rates would typically not be as accurate as a direct blood test would be. It would be important to do that 15 minute observation period because if the person had some type of alcohol coming up into their mouth or in their throat, they would need the time to make sure there had not been another one of those occurrences because if there was another occurrence, they would have to wait 15 minutes. 15 minutes is what scientists have said, but it can vary between 15 to 20 minutes depending on what state the person was in. This would be enough time for that alcohol which may have come up into the mouth, to dissipate, to burn off or to not affect the deep breath lung sample of air.

Would The Time Taken To Get To The Station Harm The Person In Terms Of Their BAC Level?

In regards to absorption and elimination of alcohol in the blood, the person might still be absorbing alcohol if they had a recent drink or they had food in their stomach, and it could take a long time and sometimes hours to fully absorb the alcohol. If the person was still absorbing the alcohol, then they might get a reading indicating they may not have fully absorbed all the alcohol but they were most likely not in an elimination stage or a peak stage or coming down. They would probably still be going up if they were still absorbing alcohol, and they would be likely to give a false positive which could possibly be higher than the person actually was. This would not be a good thing, although if the person had fully absorbed the alcohol which would take 20 to 30 minutes or an hour from the time of the arrest to the time they blew into that breath machine, then if they might have been a 0.10 or a 0.09 at the time they were arrested, they might be under a 0.08 at the time they had to blow into the evidential machine at the station. This could mean the police would not be able to file the case or we would be able to get charges reduced substantially or we would have a very good trial because we would be able to argue that the person was not at or over a 0.08 at the time of driving.

For more information on Portable Breath Test, a free initial consultation is your next best step. Get the information and legal answers you’re seeking by calling (415) 523-7878 today.

Aaron Bortel

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