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Working Principle of Alcohol Tester
The alcohol tester collects lung gas and simulates the principle of measuring the alcohol
content (BAC) in human blood. When alcohol enters the circulatory system through
digestive organs such as the stomach, intestine, liver, and so on, it is scattered in every
part of the body, including the lung organs, When blood passes through the lungs,
alcohol spreads through the capillaries into the lung cavity and into the respiratory tract.
Long-term experiments have shown that the concentration of alcohol spread through
the lungs to the respiratory tract is proportional to the concentration of alcohol in the
blood. By measuring the amount of alcohol exhaled from human lungs, the relative
alcohol concentration (BAC) in human blood is calculated by the alcohol tester. The
calculated ratio is different in different countries and for different races. The ratio is
2200:1 in China and some countries or regions. In simple terms, the concentration of
alcohol in every 2200 millilitres of breathing gas, is equal to the concentration of alcohol
in one millilitre of blood (2300:1, 2100:1, 2000:1 in other countries or regions; 2,300:1 in
Hong Kong). Alcohol tester can be used to measure the alcohol concentration (BrAC) in
the body lungs and further calculate the blood alcohol concentration in the human
body. Because sufficient gas from the lung is needed, it should be blown for at least 5
minutes when using the alcohol tester. At the same time, it is recommended that alcohol
tests take place 20 minutes after drinking, during which time you do not smoke, and that
you gargle with clear water to detect correct blood alcohol readings.