Breathalyzer Question of the Month


The team at Breathalyzer.net answers your top questions about breathalyzers!

Email your questions about breathalyzers to email (at) breathalyzer.net, and we'll choose new questions to feature in this column and in upcoming email newsletters.

Also, be sure to check our Frequently Asked Questions for more common questions about breathalyzers.



Can a BACtrack Breathalyzer really remain accurate for thousands of tests?

What is drunk walking and is it dangerous?

Can I really prevent a hangover with a breathalyzer?

Why do I sometimes wake up early after a night of drinking?

Is it true that a diet mixer will result in higher BAC than cocktails made with regular soda?

How does an air pump in a breathalyzer contribute to a higher level of accuracy?

Can a driver refuse to take a breathalyzer test if he or she is pulled over for suspicion of driving under the influence?

Guess the correct answers to the questions below, which are based on data released in April and August 2012 by the U.S. Department of Transportationís National Highway Traffic Safety Administration.
  • 1. How many people were arrested for DUI in 2009?
  • 2. How many alcohol-impaired driving fatalities were there in 2010?
  • 3. What percentage of the total motor vehicle traffic fatalities in the U.S. were alcohol-impaired-driving fatalities?


Is it true that a U.S. citizen may be denied entry into Canada if he or she has been convicted of a DUI?

How do online BAC calculators work, and what assumptions do they use?

Is it true breathalyzer results for diabetics and dieters could read higher than actual BAC estimates, and if so, why?

What is the highest BAC level ever recorded?

Why is it that men and women metabolize alcohol at different rates?

What are the three types of tests police typically use to determine a person’s BAC (blood alcohol content), and what are some considerations of each?

Is it true a person can have an estimated BAC of 0.00% after consuming one beer?

How does the legal BAC limit of .08% in the U.S. compare with the legal BAC limits imposed in other countries?

During which U.S. holiday does the greatest number of alcohol-related fatalities occur? And during which season do they most frequently occur?

Is the presence of ‘alcohol on the breath’ a reliable sign of alcohol consumption and intoxication?

Is it true that a first offense conviction for a DUI can easily cost a person $10,000? What makes it so costly?

At what rate does the body metabolize alcohol, and how can you speed up the rate at which it's metabolized?

Is there any way to trick a breathalyzer?






QUESTION: Can a BACtrack Breathalyzer really remain accurate for thousands of tests?

Yes, it can and here's the proof! This photo was taken of a BACtrack S80 Pro that was sent to BACtrack's Calibration Lab by a customer (and was recently posted on their blog.)



When the technicians ran their standard diagnostic check, the BACtrack was working well, and while it did need calibration service, it registered 2,655 tests over the previous year! That's an average of 8-9 tests per day, everyday, for a whole year.

BACtrack calibration technicians serviced the breathalyzer, re-calibrated it, and sent it back to the customer the very same day.

While this is an unusually high test count, it is proof that a regularly used BACtrack really can remain accurate over very intense testing periods.

BACtrack recommends calibration service once a year, but it is not required. Using your BACtrack regularly will actually help to maintain performance and accuracy, as moisture in the breath helps the performance of the sensor.

More about BACtrack Breathalyzer Calibration.




QUESTION: What is drunk walking and is it dangerous?

Drunk walking is exactly what it sounds like, and while it may seem to be somewhat innocuous, there is sizable data to the contrary.

A recently released government report found that more than a third of all pedestrians killed in the U.S. in 2011 had blood alcohol levels higher than the legal limit.

In fact, this Las Vegas ABC affiliate asked Sandy Heverly of the non-profit organization Stop DUI about it recently, and she said it's a trend her organization has seen for some time.

"They unintentionally step out into traffic. They step off the curb. They get in front of a vehicle and then we have another fatality or very serious injury."

All the more reason to be using a breathalyzer to measure your intoxication level--and that of your friends and family. The loss of coordination and motor skills that accompanies a BAC of 0.08% or above can be just as dangerous to a pedestrian as it can for a driver. One false move could change everything.


QUESTION: Can I really prevent a hangover with a breathalyzer?

When it comes to hangovers, prevention really is the best--some say the only--cure. But with a breathalyzer, you can effectively avoid the worst effects of a hangover--as long as you monitor your BAC closely. If you make sure you are (at most) a 0.02% when you hit the sack, you should be able to avoid a painful morning.

Nevertheless, there are times when celebrating may go a little longer or a little later than we expect. Next time you wake up feeling less than top notch, why not try one of these morning-after cures from around the globe?

  • Italy: Espresso and fruit juice.
  • Germany: Pickled herring wrapped around a pickle or an onion, otherwise known as rollmops.
  • Japan: Shijimi Soup—miso soup with raw egg and pickled plums.
  • Poland: Pickle juice straight from the jar.
  • Ecuador: Oregano tea, which is also called ‘‘chuchaqui’’ in the ancient Quechua language.
  • Ireland: Bury a person up to the neck in moist sand. When not conveniently located near a beach or playground, the Irish also favor the fry up--fried eggs, sausage, mushrooms, toast, tomato, bacon and the ever popular black pudding.  
  • Denmark: Reparationbajer—a morning-after beer, aka, hair of the dog.
  • Russia: A nice steamy sauna.
  • U.S.A.: The Prairie Oyster, or a Bloody Mary.
  • Mongolia: Pickled sheep eyeballs in tomato juice.
  • China: Strong green tea or water with lemon.
  • Switzerland: Rösti, a potato pancake made with thin, grated potatoes.
  • Korea: Haejang Guk, or "soup to chase away a hangover." Usually consists of cabbage, congealed blood, beef stock, tripe, and green onions. 



QUESTION: Why do I sometimes wake up early after a night of drinking?

Anyone having consumed alcohol in the evening knows that it can act as a sedative. Some folks even have a drink at bedtime to help them sleep. But if youíve ever woken up in the middle of the night or early morning and wondered why, hereís the answer.

Doctors Timothy Roehrs and Thomas Roth from the Henry Ford Sleep Disorders Center report that while alcohol may be good at getting you to go to sleep, it also disturbs the second half of your sleep cycle. The body, as smart as it is, makes certain adjustments to your sleep cycle when it detects alcohol in the system. However, once all the alcohol is processed by your body, these previously made adjustments to the sleep cycle continue, and that usually results in you waking up. They call it the re-bound effect.

Let's look at an example. Maureen goes to bed at midnight, when her BACtrack S80 Pro tells her that her BAC is 0.06%. Seeing as the average person processes alcohol at 0.015% per hour, it would take Maureen about four hours to process all the alcohol in her system. There's a good chance sheíll wake up, at least momentarily, at 4am.

Want to have a complete and undisturbed nightís sleep? Use a BACtrack Breathalyzer to ensure you are at 0.00% BAC before you hit the hay and wake up rested!


QUESTION: Is it true that a diet mixer will result in higher BAC than cocktails made with regular soda?

It is true.

Northern Kentucky University conducted a study breath testing college students after drinking the same amounts of alcohol. The first week they mixed their drinks with regular sodas and second week with diet. The results? Higher Blood Alcohol Content (BAC) readings with diet sodas.

The reason has to do with the difference between real sugar and sugar substitutes and how they affect the way alcohol is absorbed into the bloodstream. It turns out that the sugar in regular soda slows down the rate of alcohol absorption, whereas the substitutes do not.

Interestingly, though the subjects may have had different BACs from one week to the next, they reported not feeling any difference. Some may conclude that diet sodas could put people more at risk for drinking and driving. But here at Breathalyzer.net, we believe you should NEVER drive after drinking, even if you are under 0.08%. Only by using a breathalyzer can you check yourself and make sure you are at 0.00% BAC before getting behind the wheel.



QUESTION: How does an air pump in a breathalyzer contribute to a higher level of accuracy?

Itís important when taking a blood alcohol reading that you get air from the deepest part of your lungs. This is because the air that comes from the mouth and the esophagus is often laden with alcohol from drinking, and therefore contains a higher alcohol concentration than your blood. This is one of the reasons why users should wait 15-20 minutes after drinking to test themselves. When you get a deep lung air sample, you are getting an estimate of your actual BAC. For this reason, our pro grade units only take a sample at the very end of a five-second breathóand this is facilitated by the solenoid air pump.

The normal volume the average user breathes into a breathalyzer during a five second sample is about 5,000 mL. The first 3,500 mL is disregarded because it comes from the mouth and esophagus. Itís only in the last second or so of the sample that the air pump opens and pushes the final 1,500 mL across the sensor. This ensures the air is all coming from one direction, which is important for accuracy, and also only allows air from the deepest part of the lungs to be tested. This method will yield the most accurate BAC reading.

All of the professional grade BACtrack units use solenoid air pumps in order to achieve the most accurate readings possible.



QUESTION: Can a driver refuse to take a breathalyzer test if he or she is pulled over for suspicion of driving under the influence?

In all states, a driver can refuse to take a breathalyzer test, but refusal will result in some form of punishment due to Ďimplied consentí laws. With such laws, a licensed driver automatically consents to a future breathalyzer or similar test used to determine blood alcohol concentration when they earn the privilege to drive in a given state.

If the person pulled over for suspicion of driving under the influence is conscious, coherent and able to provide consent, the officer may offer that person a breathalyzer test and if so, must also inform them of their right to refuse it.

Penalties for refusing a breathalyzer test vary depending on the state and local jurisdiction. Typically, they involve fines of approximately $500, immediate driverís license suspension (generally 6 months), and other possible costs such as an increase in car insurance fees. In addition, refusing a breathalyzer test wonít spare a driver from a DUI. Other evidence, such as the officerís observations and other field sobriety test results, may be used against the driver.

The Bottom Line: If you are trying to beat a breathalyzer or avoid a DUI conviction, the only way to go is to monitor your alcohol consumption with a personal breathalyzer, and to simply not drink and drive.





QUESTION: Guess the correct answers to the questions below, which are based on data released in April and August 2012 by the U.S. Department of Transportationís National Highway Traffic Safety Administration.

  • 1. How many people were arrested for DUI in 2009?
  • 2. How many alcohol-impaired driving fatalities were there in 2010?
  • 3. What percentage of the total motor vehicle traffic fatalities in the U.S. were alcohol-impaired-driving fatalities?


Now for the answers:
  • 1. 1.4M people were arrested for DUI in 2009.
  • 2. In 2010, there were 10,228 fatalities in alcohol-impaired-driving crashes.
  • 3. Alcohol-impaired-driving accounted for 31 percent of the total motor vehicle traffic fatalities in the United States.




QUESTION: Is it true that a U.S. citizen may be denied entry into Canada if he or she has been convicted of a DUI?

Yes, it is indeed true! Anyone with a DWI/DUI conviction is considered to be "inadmissible" and may denied entrance to Canada. In fact, anyone with a criminal record may be denied entrance into the country.

If at least five years have passed since the original conviction date, a person may become eligible to enter the county by applying for (and receiving approval) for 'individual criminal rehabilitation.í This option involves an application, a fee and other requirements.

In addition, if at least ten years have passed since the completed conviction sentence date, a person may be deemed rehabilitated and permitted to enter the country.





QUESTION: How do online BAC calculators work, and what assumptions do they use?

Most online Blood Alcohol Content (BAC) calculators require a person to enter four data points: weight, gender, the number of drinks consumed, and the amount of time theyíve been drinking. Once the data is submitted, a formula is used to calculate the personís estimated BAC.

Many calculators employ a formula provided by the National Highway Traffic Safety Administration, which takes into account how alcohol is absorbed by the body and metabolized in the liver.

While online BAC calculators provide an approximation of a personís BAC, itís important to understand the number is just an estimate; the calculators should not be used it to decide whether or not itís safe to drive.

To prove it, take a look following assumptions used in most online BAC calculators:

  • The majority of BAC calculators have predefined values for both alcohol serving size and alcohol content. For instance, a beer is 12 oz and 4.5% alcohol content, a glass of wine is 4 oz and 15% alcohol content and a shot is 1.5 oz and 40% alcohol content. If you're consuming a drink with a larger serving size and/or one thatís stronger than average, the calculator will underestimate your BAC.


  • BAC calculators do not take into account the amount of food in your stomach. A personís BAC rises faster when they consume alcohol on an empty stomach since thereís no food to dilute the alcohol.


  • BAC calculators assume your alcohol consumption is consistent over a specified period of time. For instance, when you drink two drinks in two hours, the calculator assumes you have consumed one drink per hour. If drinks are consumed more quickly, your estimated BAC will be miscalculated.


  • BAC calculators use a formula based on average values – the average amount of water in the body and in the blood, and the average metabolism rate. Individual factors that affect these values and are not calculated in a BAC estimate.


  • On the other hand, a breathalyzer will provide a much more accurate estimate of a personís BAC because they provide values based on a personís deep lung breath sample. (All the more reason to shop for a BACtrack Breathalyzer now!).





    QUESTION: Is it true breathalyzer results for diabetics and dieters could read higher than actual BAC estimates, and if so, why?

    Breathalyzer results for diabetics could read higher than actual BAC estimates because, according to the NHTSA (National Highway and Traffic Safety Association), these individuals can have high levels of acetone in their breath. The same goes for individuals on extreme diets including fasting and low carb diets.

    Acetone is a substance that is falsely identified as ethanol (also called ethyl alcohol) by some breath alcohol testers.

    However, whether or not the presence of acetone will affect a breathalyzer reading depends on the actual breathalyzer used for testing. Breathalyzers with fuel cell sensor technology, such as the BACtrack S80 Pro, BACtrack S75 Pro, and the BACtrack Element, are all non-responsive to acetone.




    QUESTION: What is the highest BAC level ever recorded?

    According to CBC News Canada, a Bulgarian man holds the record for the highest BAC level ever recorded, and specifically ‐ the highest survivable BAC level.

    In December 2004, a 67-year-old man in Plovdiv, Bulgaria was taken to the hospital to be treated for minor injuries he suffered following a car accident. The man appeared to be fine and communicated cohertently with doctors, yet his BAC was recorded at .914%. Assuming the testing equipment was malfunctioning, doctors performed five separate lab tests to confirm the manís BAC level. This level is nearly double the level considered to be fatal, and nearly 11 times higher than the U.S. legal limit of .08 %BAC!




    QUESTION: Why is it that men and women metabolize alcohol at different rates?

    Men and women metabolize alcohol differently, and itís not just because women typically weigh less than men. There are two additional factors that come into play.

    First, women typically have a higher percentage of body fat compared to men, and because fat cannot absorb alcohol, itĎs concentrated at higher levels in the bloodstream. Second, women produce less of the stomach enzyme called dehydrogenase, which breaks down or metabolizes alcohol in the stomach. As a result, women absorb more alcohol into the bloodstream than men.




    QUESTION: What are the three types of tests police typically use to determine a person’s BAC (blood alcohol content), and what are some considerations of each?

    Three tests are typically used to measure a person's blood alcohol concentration (BAC), and measuring a person’s BAC is the most commonly used metric of alcohol intoxication for legal or medical purposes.

    Law enforcement may choose to conduct one, two or all three tests, depending on the situation and applicable state laws. In some cases, a person may choose which test they’d like performed. While police officers often conduct various field sobriety tests, these tests only measure your reflexes and abilities, not your BAC.

    The three tests are detailed below, along with additional information about each.

    Breathalyzer/Breath Test. This test measures the amount of alcohol in the lungs, and is the most common type of blood alcohol test performed by law enforcement. Because of the high alcohol content remaining in the mouth and the upper digestive system, the breath test may inaccurately read high if it’s given soon after your last drink. (This is why we tell you to wait 20 minutes after your last drink to conduct a test).

    Blood Test. This test measures the amount of alcohol found in a person’s blood stream, and is considered the most accurate test. It requires a qualified medical professional to draw a sample of your blood for testing, and will also show any presence of drug use.

    Urine Test. This test measures the amount alcohol in the urine, and is the least accurate and the least reliable of the three tests. Since test results are based on alcohol content in your excreted urine, there may be a greater amount of alcohol in your urine versus the amount of alcohol you actually have remaining in your system. Like the blood test, this test also measures the presence drugs as well as alcohol.



    QUESTION: Is it true a person can have an estimated BAC of 0.00% after consuming one beer?

    The answer is a surprising yes, and this is actually one of our most common customer questions. It’s very common for people, especially men, to drink one beer and register a 0.00 %BAC on a breathalyzer 30 or 60 minutes later.

    How come? Your body processes alcohol as soon as you start drinking, so your body begins absorbing, processing, and then eliminating the alcohol you consumed immediately upon your first sip. That being said, if your %BAC were 0.08 and you were no longer drinking, your BAC one hour later would likely be close to 0.06 %BAC. The average adult male eliminates 0.015 – 0.020 %BAC from his bloodstream every hour.

    Similarly, one beer of standard alcohol concentration can raise the average adult male’s BAC 0.015 %BAC. However, if the beer’s alcohol is not absorbed into the bloodstream immediately and the %BAC is not tested immediately, the body has processed out some (or all) of that one beer’s alcohol by the time the %BAC is tested with a breathalyzer. It’s when people consume multiple drinks an hour that the BAC level really starts to go up.

    For instance, if you drank the beer in 10 minutes and waited 30 minutes after testing, it’s very likely your BAC would be at or very close to zero. If you had a meal prior to the beer, or are above the average male weight, it’s even more likely that your true %BAC was at or close to 0.000 %BAC. And in many cases, a true 0.002 %BAC or below (a very, very slight level -- NOTE 0.002 not 0.02) will register 0.000 %BAC, which ensures that any alcohol in the environment, say, at a bar, doesn’t register a false positive for the test taker.




    QUESTION: How does the legal BAC limit of .08% in the U.S. compare with the legal BAC limits imposed in other countries?


    Since 2002, it has been illegal in all 50 U.S. states for those over the age of 21 to drive with a blood alcohol concentration (BAC) that is .08% or higher, and before 2002, the legal limit was .10%.

    In addition, some states include a lesser charge, typically called "driving while impaired," with a target BAC of .05%. Also, drivers under 21 in the U.S commonly must adhere to lower legal limits, typically 0.01% to 0.05%.

    But how do these limits compare with BAC limits in other countries – is the U.S. more or less lenient when in comes to driving under the influence of alcohol?

    It turns out that most countries have far stricter BAC laws than the U.S., and there has been a downward trend in further decreasing the limits in an effort to curtail drinking and driving fatalities.

    For some countries, laws are not standardized at the national level, but instead they vary by state or province, and they may also vary by the class of driver. For instance, the BAC limit is lower for new drivers, and/or professional drivers such as those that drive taxis and buses, and/or for those on motorbikes.

    There are countries with a zero-tolerance policy and as such, it’s illegal to have any alcohol in the blood while driving in these countries. Armenia, Azerbaijan, the Czech Republic, Hungary, Jordan, Kyrgyzstan, and Romania, are just a few countries with this limit.

    At the .02% BAC limit, you’ll find China, Estonia, Poland, Sweden and others, and countries with the .03% BAC limit include Serbia, Japan, and Uruguay.

    A .05% BAC legal limit is the most common and found in most Western European countries among others. Argentina, Australia, Austria, Belgium, Finland, France, Germany, Greece, Hong Kong, Israel, Italy, South Africa, Spain, Switzerland, Thailand, Taiwan, Turkey, and others all have this legal limit.


    Joining the U.S. with a 08% BAC legal limit are Malaysia, Mexico, New Zealand, Norway, Puerto Rico, Singapore, and the United Kingdom, among others.




    QUESTION: During which U.S. holiday does the greatest number of alcohol-related fatalities occur? And during which season do they most frequently occur?

    Most people believe New Year's Eve is the U.S. holiday with the highest frequency of drunk driving fatalities, and it’s a good guess. However, according to the National Highway Traffic Safety Administration (NHTSA), in terms of a single holiday, Thanksgiving is when most alcohol-related fatalities occur. This is because the risk increases when drinking is combined with heavy traffic and long-distance car trips.

    The National Highway Traffic Safety Administration (NHTSA) also describes the ‘100 Day of Summer,’ the period of time from Memorial Day to Labor Day, and especially around major holidays like July 4th, as one of the most dangerous and deadliest times of the year on the Nation’s highways. It’s a time when there’s a significant increase in alcohol-related traffic crashes and fatalities. In fact, Fourth of July weekend proves to be the deadliest of all when looking at total fatalities for a four-day weekend, and 40 percent of them are attributed to driving while under the influence of alcohol.



    QUESTION: Is the presence of ‘alcohol on the breath’ a reliable sign of alcohol consumption and intoxication?

    ‘Alcohol on the breath’ is not a reliable sign because alcohol is actually odorless. When people detect ‘alcohol on the breath,’ it’s actually the odor of things commonly found in alcoholic beverages. For instance, the breath of a person who drinks a non-alcoholic beer and a beer containing alcohol will smell the same.

    In a study to test whether estimates of alcohol on the breath were reliable (Moscowitz, H., Burns, M. & Ferguson, S. Police officers’ detection of breath odors from alcohol ingestion, Accident Analysis and Prevention, 1999), experienced police officers were asked to detect an alcohol odor from 14 subjects. The subjects were at blood alcohol concentrations (BACs) ranging from zero to 0.13, and odor detection was over a 4 hour period, and before and after the subjects consumed food.

    The result: Odor strength estimates were unrelated to BAC levels and estimates of BAC level failed to rise above random guesses. The researchers concluded that estimates of alcohol on the breath cannot be relied upon.




    QUESTION: Is it true that a first offense conviction for a DUI can easily cost a person $10,000? What makes it so costly?

    Yes, it’s absolutely true. Costs for a first time DUI conviction are typically $10,000 and up. The costs further skyrocket if you hit something or hurt somebody – and with the latter, clearly the costs are not just monetary.

    Costs vary depending on the state and situation, and typically include the following:

    • Fines and court fees: $500-1,200
    • Bail: $150-2,500
    • Towing: $100-600
    • Alcohol Education and Treatment: $300 and up
    • Alcohol Evaluation: $200 and up
    • Driving/Alcohol-Awareness School: $400 and up
    • License Reinstatement Fee: $100-250
    • Attorney Fees: $2,500-5,000 and up
    • Auto Insurance Increase (3-5 years): $4500 and up
    • Miscellaneous additional fees: $200




    QUESTION: At what rate does the body metabolize alcohol, and how can you speed up the rate at which it's metabolized?

    Once alcohol reaches the bloodstream, it is generally metabolized at the rate of .015 of blood alcohol concentration (BAC) every hour, which can be estimated as one average drink of alcohol per hour.

    However, many factors influence this rate and these include gender, weight and body composition, the contents of the stomach (for instance, if a person has eaten before or during alcohol consumption) a person’s general health and even the efficiency of the liver.

    A person cannot increase the rate at which their body metabolizes alcohol. While it’s commonly believed that drinking coffee, taking a cold shower or exercising can speed up the rate at which alcohol is metabolized by the body, the passage of time is the only factor affecting the rate. The only control a person has over their BAC is to increase it by drinking alcohol.




    QUESTION: Is there any way to trick a breathalyzer?

    There are a number of techniques and substances that are thought to be able to "trick" a breathalyzer into giving a lower blood alcohol content reading. These include eating an onion or garlic, sucking on a copper penny and more. Below are some of the common myths and facts about trying to fool a breathalyzer.

    Myth: Eating strong foods like onions, coffee grounds and breath mints. These substances often mask the odor of alcohol on a person’s breath, but it doesn't change the alcohol content in their system. When a person blows into a breathalyzer, the blood alcohol level of air in the deep lungs, not the mouth, is measured. It is this value that is then converted into the corresponding Blood Alcohol Content (%BAC) estimate.

    Myth: Drinking mouthwash. Mouthwash may be able to slightly mask the smell of alcohol on your breath, but like any other strong substance, it won't lower a breathalyzer reading. In fact, mouthwash contains a small amount of alcohol that could potentially increase the amount of alcohol registered on the breathalyzer whether a person was drinking or not. The same goes for some breath sprays. On a related note, testing is most accurate if subjects have not consumed any substance 15 minutes prior to testing to ensure that there is no residual mouth alcohol.
    See BACtrack Breathalyzers featured on the Dr. Phil Show to see actual tests conducted with these substances.

    Myth: Place pennies or a battery in your mouth. Pennies supposedly produce a chemical reaction, although it’s thought possible because they are made of copper, when in fact, pennies are mostly zinc or steel and copper-coated now. Meanwhile, batteries supposedly create an electrical charge. These methods were proved to be ineffective at lowering a person’s blood alcohol content on a Mythbusters episode. The other issue with either of these methods would be the difficulty in by placing something in one’s mouth and removing it without a police officer noticing.
    See BACtrack Breathalyzers featured on the Mythbusters episode dispelling breathalyzer myths.

    Fact: While there are many myths that are assumed to help trick a breathalyzer, is there a tried and true method to decrease a BAC reading? Of course and it’s quite simple – play it safe and don't drink and drive.