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« DUI Defense Strategies: Breath Alcohol Testing Errors

Many factors render BAC testing which are even more tending to inaccurate results than the field tests.

Errors Inherent In Blood and Breath Tests for Intoxication

If we assume that the test machines are in standard calibration and that the administration of tests were flawless which is a rare scenario, still it is acknowledged by the experts that DUI breath tests possess an error rate of plus or minus .02%, and there is an error rate of plus or minus .005% in blood tests.

By adding up factors below, about test results further questions can be raised. If you give a second test, which is within your rights, the readings must be within .02% of each other in accordance with the California law that governs Breath Testing.

breath test

Heartburn Can Give a Falsely High Reading

The breath test is designed for the purpose of testing the amount of alcohol present in the air in your lungs. In case if you are suffering from heartburn, GERD (gastroesophageal reflux disease) or acid reflux, alcohol from the stomach can move back from the stomach to the throat or mouth. When you blow into the breath test machine, the mouth alcohol plus the air in your lungs is measured in these instances.

This could become the reason to increase your reading on the test falsely by a factor of 4, which means that an actual blood alcohol concentration of .04 would read as .16, which is double the legal limit. In case if you had just eaten a spicy meal and also you were experiencing heartburn when you perform the test, you probably give a very high false reading. Even a very minor, unnoticeable regurgitation can result in mouth alcohol being blown on the test.

Mouth Alcohol from Other Sources Can Also Affect Test Results

There are other sources of mouth alcohol in addition to belching or heartburn. Decaying food particles trapped between the teeth or in dentures, braces, cavities or impactions will give rise to the formation of alcohol in the mouth. And the latent alcohol from having recently taken cough syrup, cold medicine, homeopathic preparations, and mouthwash or used various breath fresheners could also be the source of mouth alcohol.

Same as alcohol burped up from acid reflux, latent alcohol in the mouth which arises from these sources can also become the cause of dramatically increasing the breath test results.

The Machines Also Read Other Chemicals

People who work around chemicals might also absorb these compounds and these

compounds may show up in lung tissue. Such type of things as nitrous oxide, acetonitrile, ethylene, toluene, isopropanol, if sound in the lung tissue of a DUI suspect, can probably give a falsely high reading on the breath test.

Test results can be falsely elevated by the recent exposure to any type of volatile fumes such as gasoline, paint, lacquer, etc.

A low-Carb Diet Can Fool the Machine

When a person is eating a high protein, low carbohydrate diet, such as the Adkins diet, compounds called ketones are produced by the body during metabolism. After that if a person consumes carbohydrates, as in drinking alcohol, these ketone bodies in the blood are able to produce another form of alcohol, called isopropyl alcohol.

The two alcohols are not distinguished by most breath testing machines even though impairment is caused by ethanol only. It can result into a falsely high test result.
If you are hypoglycemic, borderline diabetic or if you have diabetes, then the consumption of alcohol, even in small amounts, will cause your body to convert elevated levels of acetone into isopropyl alcohol.

Your Blood Alcohol Level Was Still Rising

When you consumed your alcohol it may have more bad results on your test reading than how much you consumed. The reason behind his is that alcohol can take up to 3 hours to absorb fully into the bloodstream. If I explain it in other words, your peak level BAC may come at the station when taking the breath test and it could become twice as high as your level when you were stopped, especially if you consumed the alcohol shortly before you were stopped.

When you were stopped your BAC level may have been .07 but an hour later at the police station when the alcohol has been fully absorbed, the test reads .14. No law mandates against a BAC level above .08 at a police station; the level that is counted is the level when you were driving. This one is another potential source of inaccuracy in breath testing.Drink driving

While alcohol is being absorbed, in your arteries the BAC content of the blood may be 60% which will be higher than the content of the blood in your veins. As a consequence of this the reading of the deep lung air may give a falsely high reading due to the arterial blood that supplies the lungs.

Also, if you would be able to prove that sufficient alcohol was consumed while you were driving or after that you have ended driving but before the police arrived, you would be able to present a successful defense.

Individual Variations in Your Ratio of Blood to Breath

Across the general population, the breath machines use a conversion ratio to convert a breath alcohol reading to a blood alcohol reading. This value is assigned by the machine at 2100 to 1. is This assumption is fundamental to breath testing, that the subject being tested conforms to this ratio.

However, different ratios among individuals across the population have been disclosed widely by the scientists. And, if a person’s breath-to-blood conversion ratio is lower than 2100 to 1, a breath test will show a blood alcohol level much higher than what it actually is.

Breathing Techniques and Temperature Can Affect Test Results

A false high or a false low reading could happen due to the variation in the duration and volume of the breath sample may result. The machine is calibrated to receive a breath sample that might lasts over 10 seconds in delivery time, which normally translates to the delivery of approximately 2 liters of air. By a longer breath sample a much higher amount of alcohol being registered may yield. Opposite to it, a shallow breath or hyperventilating may result in mouth alcohol being blown, which again give a false high reading.

Even the results may be affected by breath temperature. The machines are calibrated to record breath blown at a temperature of 34 C., which are just a few degrees below normal body temperature. Even though a slightest temperature increase can give a falsely higher reading. This thing can occur from fever, sitting in the back of a hot squad car, exertion from dancing at a club, sitting in a hot tub and many more reasons.

Many persons are not suitable candidates for breath alcohol testing due to various physical conditions such as chronic lung problems (emphysema, asthma, bronchitis or chronic obstructive pulmonary syndrome) or dental problems, yet these same individuals are given breath alcohol tests day in and day out, with the same machine that use to take other persons breath test.

Test Results May Be Contaminated

Radio waves that are being generated by any number of electronic devices such as police radios, radar guns, scanners, computer, etc., are able to interfere with electronic circuitry in blood or breath testing machines. Breath machine can be influenced by the radio frequency interference, or RFI as it is known, and it results into false test reading. While it is difficult to determine the amount of inaccuracy, it nevertheless adds yet one more degree of skepticism surrounding breath alcohol tests.

A Disconnect May Exist Between Intoxication Symptoms & BAC Test Results

A BAC reading is one of the many factors in a DUI case. Sometimes it happens that the test reading is inconsistent with other evidence such as the field sobriety tests, officer reports of the suspect’s behavior, etc. As well, at different levels of intoxication specific symptoms can be observed and if the DUI suspects other indicators do not give a conformation to what would be expected from his test results, then this disconnect calls the entire case into question. That is, at the reported BAC test results the expected level of impairment was not evident.breathalyzer3

Many factors render BAC testing which are even more tending to inaccurate results than the field tests.

Errors Inherent In Blood and Breath Tests for Intoxication

If we assume that the test machines are in standard calibration and that the administration of tests were flawless which is a rare scenario, still it is acknowledged by the experts that DUI breath tests possess an error rate of plus or minus .02%, and there is an error rate of plus or minus .005% in blood tests. By adding up factors below, about test results further questions can be raised. If you give a second test, which is within your rights, the readings must be within .02% of each other in accordance with the California law that governs Breath Testing.

Heartburn Can Give a Falsely High Reading

The breath test is designed for the purpose of testing the amount of alcohol present in the air in your lungs. In case if you are suffering from heartburn, GERD (gastroesophageal reflux disease) or acid reflux, alcohol from the stomach can move back from the stomach to the throat or mouth. When you blow into the breath test machine, the mouth alcohol plus the air in your lungs is measured in these instances.

This could become the reason to increase your reading on the test falsely by a factor of 4, which means that an actual blood alcohol concentration of .04 would read as .16, which is double the legal limit. In case if you had just eaten a spicy meal and also you were experiencing heartburn when you perform the test, you probably give a very high false reading. Even a very minor, unnoticeable regurgitation can result in mouth alcohol being blown on the test.

Mouth Alcohol from Other Sources Can Also Affect Test Results

There are other sources of mouth alcohol in addition to belching or heartburn. Decaying food particles trapped between the teeth or in dentures, braces, cavities or impactions will give rise to the formation of alcohol in the mouth. And the latent alcohol from having recently taken cough syrup, cold medicine, homeopathic preparations, and mouthwash or used various breath fresheners could also be the source of mouth alcohol.

Same as alcohol burped up from acid reflux, latent alcohol in the mouth which arises from these sources can also become the cause of dramatically increasing the breath test results.

The Machines Also Read Other Chemicals

People who work around chemicals might also absorb these compounds and these compounds may show up in lung tissue. Such type of things as nitrous oxide, acetonitrile, ethylene, toluene, isopropanol, if sound in the lung tissue of a DUI suspect, can probably give a falsely high reading on the breath test.
Test results can be falsely elevated by the recent exposure to any type of volatile fumes such as gasoline, paint, lacquer, etc.

A low-Carb Diet Can Fool the Machine

When a person is eating a high protein, low carbohydrate diet, such as the Adkins diet, compounds called ketones are produced by the body during metabolism. After that if a person consumes carbohydrates, as in drinking alcohol, these ketone bodies in the blood are able to produce another form of alcohol, called isopropyl alcohol.

The two alcohols are not distinguished by most breath testing machines even though impairment is caused by ethanol only. It can result into a falsely high test result.
If you are hypoglycemic, borderline diabetic or if you have diabetes, then the consumption of alcohol, even in small amounts, will cause your body to convert elevated levels of acetone into isopropyl alcohol.

Your Blood Alcohol Level Was Still Rising

When you consumed your alcohol it may have more bad results on your test reading than how much you consumed. The reason behind his is that alcohol can take up to 3 hours to absorb fully into the bloodstream. If I explain it in other words, your peak level BAC may come at the station when taking the breath test and it could become twice as high as your level when you were stopped, especially if you consumed the alcohol shortly before you were stopped.

When you were stopped your BAC level may have been .07 but an hour later at the police station when the alcohol has been fully absorbed, the test reads .14. No law mandates against a BAC level above .08 at a police station; the level that is counted is the level when you were driving. This one is another potential source of inaccuracy in breath testing.

While alcohol is being absorbed, in your arteries the BAC content of the blood may be 60% which will be higher than the content of the blood in your veins. As a consequence of this the reading of the deep lung air may give a falsely high reading due to the arterial blood that supplies the lungs.

Also, if you would be able to prove that sufficient alcohol was consumed while you were driving or after that you have ended driving but before the police arrived, you would be able to present a successful defense.

Individual Variations in Your Ratio of Blood to Breath

Across the general population, the breath machines use a conversion ratio to convert a breath alcohol reading to a blood alcohol reading. This value is assigned by the machine at 2100 to 1. is This assumption is fundamental to breath testing, that the subject being tested conforms to this ratio.

However, different ratios among individuals across the population have been disclosed widely by the scientists. And, if a person’s breath-to-blood conversion ratio is lower than 2100 to 1, a breath test will show a blood alcohol level much higher than what it actually is.

Breathing Techniques and Temperature Can Affect Test Results

A false high or a false low reading could happen due to the variation in the duration and volume of the breath sample may result. The machine is calibrated to receive a breath sample that might lasts over 10 seconds in delivery time, which normally translates to the delivery of approximately 2 liters of air. By a longer breath sample a much higher amount of alcohol being registered may yield. Opposite to it, a shallow breath or hyperventilating may result in mouth alcohol being blown, which again give a false high reading.

Even the results may be affected by breath temperature. The machines are calibrated to record breath blown at a temperature of 34 C., which are just a few degrees below normal body temperature. Even though a slightest temperature increase can give a falsely higher reading. This thing can occur from fever, sitting in the back of a hot squad car, exertion from dancing at a club, sitting in a hot tub and many more reasons.

Many persons are not suitable candidates for breath alcohol testing due to various physical conditions such as chronic lung problems (emphysema, asthma, bronchitis or chronic obstructive pulmonary syndrome) or dental problems, yet these same individuals are given breath alcohol tests day in and day out, with the same machine that use to take other persons breath test.

Test Results May Be Contaminated

Radio waves that are being generated by any number of electronic devices such as police radios, radar guns, scanners, computer, etc., are able to interfere with electronic circuitry in blood or breath testing machines. Breath machine can be influenced by the radio frequency interference, or RFI as it is known, and it results into false test reading. While it is difficult to determine the amount of inaccuracy, it nevertheless adds yet one more degree of skepticism surrounding breath alcohol tests.

A Disconnect May Exist Between Intoxication Symptoms & BAC Test Results

A BAC reading is one of the many factors in a DUI case. Sometimes it happens that the test reading is inconsistent with other evidence such as the field sobriety tests, officer reports of the suspect’s behavior, etc. As well, at different levels of intoxication specific symptoms can be observed and if the DUI suspects other indicators do not give a conformation to what would be expected from his test results, then this disconnect calls the entire case into question. That is, at the reported BAC test results the expected level of impairment was not evident.

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2 commentsto “DUI Defense Strategies: Breath Alcohol Testing Errors”

  • July 6, 2009
    anu wrote

    Express Labs was started to help companies avoid hiring individuals who abuse drugs and alcohol. Having a Drug Free Workplace can significantly decrease safety and health hazards. Additional costs associated with drug and alcohol abuse include: Lateness, absenteeism, decreased productivity, short-term disability claims and employee turn-over. Even if you have a drug testing program in place, we can still provide you with our services. We are a Preferred Collection Site for Quest Diagnostics, LabCorp, Kroll and MedTox.

  • August 30, 2009
    Paul Narrero wrote

    The state of Wyoming, Laramie County, apparently uses the EC/IR-II made by intoximeter. Can a combination of GERDS, coppenhagen pouch tobacco, and dentures using denture adhesive affect the results of a breath reading? I also learned that the Cheyenne police dept. may have disabled the IR feature which is supposed to detect mouth alcohol! They said that it was a very time consuming process. If the dept. did disable this feature, how can I find out?

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