principle of operation, interpretation of readings, calibration


Motorists, professional drivers and their superiors will not be superfluous to know how the breathalyzer is operated — a device that measures the amount of alcohol in the blood. It is used by the traffic police, and in order to avoid ambiguous situations, you should have some knowledge about this device.

Where is breathalyzer used?

The breathalyzer is device for determining the degree of intoxication. It is no secret that even a small amount of alcohol can cause lethargy, an increased desire to fall asleep, and negatively affect attentiveness. Obviously, a drunk person in a car is a danger to himself and those around him. That is why special attention is paid to this issue, and violations of the rules are severely prosecuted by law.


Most often, a breathalyzer is needed traffic police officers to determine the sobriety of motorists on the road, but the device is widely used in other areas.

  1. Transport organizations check their drivers before going on the route.
  2. Drivers of school buses and other municipal institutions are subjected to a similar check.
  3. The device is used in the event of legal disputes.
  4. Employees of public and private companies engaged in work with harmful and dangerous substances, as well as complex mechanisms or working in extreme conditions are subject to periodic inspections.
  5. A breathalyzer is needed to control problem children, adolescents.

Policeman with breathalyzer

The areas listed above are far from the only places where the device is used. Breathalyzer can be useful ordinary driverafter all, there are cases when the next morning after the holiday it is necessary to leave by car, and at the same time there can be no confidence that there is no alcohol left in the blood without checking.

Types of testers

The breathalyzer works by sensors that measure the level of alcohol-containing substances in the air.. When a person drinks alcohol, it is carried through the blood to all parts of the body, including the lungs, and from them alcohols remain in the air that the driver exhales. Sensors are divided into several types.

  1. Semiconductor (differ in the lowest accuracy), deviations in the accuracy of readings up to 20%.
  2. Electrochemical (the most accurate data), the error is up to 0.01 ppm or no more than 10% of the final result.
  3. infrared, photometric (they do not lose their functions over time, this is how they compare favorably with the first type), the error of the breathalyzer is up to 10%.

Types of breathalyzers

All devices are available with or without a mouthpiece. Models without a mouthpiece called non-contact, since the subject, when exhaling, holds the device at a distance of no more than 2 cm from the mouth and blows into a special hole.

Important! Devices without a mouthpiece are considered less accurate, since in this case, part of the exhaled air is scattered, and it is not possible to determine the exact level of ethanol.

Breathalyzer with mouthpiece is a contact variant, where the user takes a plastic straw to their lips and blows into it. Air is not dissipated and the results are more accurate. For hygiene purposes, the kit may include several replaceable plastic straws.

Breathalyzer with mouthpiece

How does a breathalyzer work?

The instructions for the device give an understanding of how to use a breathalyzer of one kind or another, but in general the process is quite similar.

  1. The device is turned on by means of a special button.
  2. The mouthpiece is connected.
  3. The test subject breathes into the tube until a double beep sounds.
  4. The processor counts the amount of ethanol and displays the result on the screen.

On a note! Depending on the device, the designation of the indicator may be different — in ppm, mg / liter, fractions of a percent.

As mentioned above, the principle of operation of the breathalyzer is based on determining the amount ethanol content in the airthat the subject exhales. Based on this, it is possible to find out how drunk he was when he drank alcohol, as well as how much alcohol remained in his blood if the drinks were taken on the eve of the trip. When air enters the device, the sensor transmits a signal to a special processor, which performs specific final calculations. The sensors themselves analyze the air in different ways:

  • electrochemical monitors the reaction of reagents to the contained ethanol;
  • semiconductor analyze the amount of heat released as a result of a chemical process that begins with the content of alcohols in the body;
  • infrared capture ethanol vapor.


Valid values

Below is a table with the content of alcohol in the blood and the possible reaction of the body.

Breathalyzer readings in ppm Degree of intoxication Symptoms
0.3-1.5 ppm Light Talkativeness, arrogance, fits of anger. Attention, the angle of vision decreases, the perception of colors may change.
1.5-2.5 ppm Medium Nausea, dizziness, weakness, unsteady gait. Most often accompanied by high spirits and self-confidence, which causes thoughts about the safety of the trip.
2.5-3.5 ppm heavy Vomiting, inability to orientate in space, death.

It is worth noting that 3.5 ppm is considered a lethal dose for humans. Depending on the type of device, the designation can be displayed in numerical values, the color of the screen changes (green, yellow, red), the arrow on the table indicates the result.

Important! Before agreeing to be tested, a motorist should know that Russian law allows 0.365 ppm, which is equivalent to 0.16 ml / liter. In Europe, 0.8 ppm is considered acceptable.

Why breathalyzer can give false readings

There is a situation in which a police officer stops the driver and offers him to undergo an alcohol test. The car enthusiast, in full confidence that nothing threatens him, because he really did not drink, agrees to the test, and the breathalyzer shows that there is ethanol in his blood. It is important to know that some drinks and foods can cause a similar reaction and give a false result, and in addition, some people have a slightly higher indicator for health reasons. To avoid misunderstandings and erroneous punishment, you should know what can cause a tester’s reaction:

  • soft drinks (kvass or beer);
  • pharmaceutical products containing alcohol;
  • sweets with alcohol (tests were carried out, and the result showed that four sweets leave a mark, it completely disappears only an hour after ingestion);
  • kefir or curdled milk;
  • raisins or grapes, which can cause stomach fermentation;
  • black bread, overripe bananas, oranges, desserts;
  • regularly used inhalers;
  • a cigarette can add two hundredths to the final result.

In addition to the above, the following reasons may affect the breathalyzer readings:

  • elevated temperature of the test;
  • hereditary deviations from the norm;
  • evaporation of paint and varnish products;
  • temperature at the test site;
  • certain types of diseases (diabetes);
  • tester not calibrated.

What is calibration for?

Breathalyzer calibration is a mandatory procedure for models that are reusable. Laboratory studies have shown that each test on any type of tester affects the state of the sensor, reducing its sensitivity. In the description of the device, this moment is indicated. Another nuance shows that the tester can fail and start showing inaccurate data if saliva is deliberately placed in it or tobacco smoke is exhaled. As a rule, the instructions indicate the service life of the breathalyzer, as well as when it is necessary to adjust the sensitivity of the sensor or carry out its complete replacement. Some models have self-diagnosis function and are able to indicate the need for calibration.


Models with a semiconductor sensor need to be tested and the sensor replaced after 200-300 checks, provided that professional devices are used 20-30 times a day, and individual devices 2-3 times a day. If the frequency of use is significantly less, then verification of the breathalyzer and its calibration are needed once a year. Professional Models are given to special metrological services after every 500-1500 applications, depending on the frequency of daily use.

On a note! You can repair a breathalyzer for individual purposes yourself, you just need to buy a new sensor.

Common myths

There are some myths and misconceptions among drivers that sometimes cause a desire to take risks and go on a trip after drinking. The most popular ones are listed below. It is worth familiarizing yourself with the list so as not to get into an unpleasant situation of deprivation of rights due to a stupid mistake.

  1. There is a myth that tester won’t show beer — this is a delusion, any alcohol-containing drink gives ethanol in the blood.
  2. Food in large quantities neutralizes alcohols.
  3. Burping also does not improve the situation with the alcohol content.
  4. Chewing gums, sprays, aerosols that can mask the smell are not able to eliminate traces of alcoholic beverages.
  5. Battery or copper coin — another stupid myth, while the presence of such objects in the mouth will definitely raise questions from traffic police inspectors.

As a conclusion, it is worth noting that no matter how the driver feels immediately after or the morning after drinking alcohol, you should not neglect your own and other people’s lives, and also spoil your future. There are no situations in which going by car is a necessity and worth the risk. And the question is not even the possibility of being caught, but in relation to others, because according to statistics, drunk drivers kill people in much larger numbers than they themselves die.

The most reliable breathalyzers

Breathalyzer Alcogran AG-100 on Yandex Market

Breathalyzer Airline ALK-D-02 on Yandex Market

Breathalyzer Dingo AT-2020 on Yandex Market

Breathalyzer Inspector AT600 on Yandex Market

Breathalyzer AlcoHunter Professional X on Yandex Market


Добавить комментарий