Breathalyzer is a device capable of measuring the percentage of alcohol in the blood, allowing you to assess whether the person is capable of performing more complex and life-threatening tasks such as driving or operating heavy machinery.
Thus, this type of device is widely used by police to quantify the blood alcohol levels of people who appear drunk or just as a routine test.
1. How does the appliance work?
In most breathalysers, when breathed into the apparatus, it collects about 1 mL of the expired air and places it on a reactive cell. Upon reacting, the cell releases a small electrical discharge, which is measured by the apparatus.
Depending on the size of the reaction and the discharge, the breathalyser is able to identify the amount of alcohol that is present in the exhaled air and then makes a new evaluation to indicate what percentage of alcohol that amount represents in 100 mL of blood.
2. What percentages of alcohol are allowed?
According to the National Traffic Council the maximum limit for a person not to be fined is 0.05 mg of alcohol per liter of air, evaluated by the breathalyzer. If a blood test is done, this value is 2 dg per liter of blood.
3. Is it possible to deceive the breathalyzer?
Breathalyzer is an extremely sensitive device that uses chemical reactions to produce the result, so techniques like chewing a chewing gum, drinking vinegar or sucking ice do not change the result, and can even cause injuries to the body.
4. Why can alcohol be measured in the breath?
Drink alcohol is known scientifically as ethanol and has a very small molecule that can easily pass through the stomach walls and reach the blood vessels, quickly passing into the blood.
Once the body is at a temperature of approximately 37 ° C, the alcohol evaporates and, when this happens, it is transported to the pulmonary alveoli where it is then eliminated through the exhaled air.
Thus, the greater the amount of alcohol ingested, the greater the concentration of ethanol in the lungs and, consequently, in the air expired.
5. Is the result always reliable?
The breathalyser should be calibrated regularly to ensure that the result is reliable. For this, a bottle of compressed air is used which contains an exact percentage of 0.08 mg of alcohol. When this air is expelled and the breathalyzer gives a different result, it must be evaluated by the company that produced it.
Thus, whenever a breathalyzer test is performed, there should be a sheet that ensures that a regular calibration of the apparatus has been performed.
