Why can an alcohol analyzer tell whether a person has drunk alcohol?

How can a breathalyser tell if someone has been drinking?

Ethanol is the main component of wine. It has an important chemical property, which is that it can be oxidized by oxidizing substances. The alcohol analyzer used by traffic police contains a sensitive material, a gas sensitive resistor, which is a highly active metal oxide semiconductor.

When the concentration of reducing gas alcohol increases, an oxidation-reduction reaction will occur between the two, causing the resistance value of the gas-sensitive resistor to decrease, thereby causing changes in the current and voltage in the circuit. The alcohol concentration can then be reflected by the change in resistance.

Specifically, the alcohol content in the exhaled gas has a certain proportional relationship with the alcohol content in the blood, and different concentrations of alcohol content will cause the sensor to generate voltage signals of different strengths. Finally, the signal is amplified by the light-emitting diodes in the circuit. The higher the alcohol gas concentration, the more light-emitting diodes are connected, and the brighter it is; the lower the gas concentration, the fewer light-emitting diodes are connected, and the darker it is. If it exceeds a certain standard value, the buzzer on the alcohol analyzer will sound.

If you consume too much alcohol and it does not have time to metabolize it, it will have an inhibitory effect on the central nervous system, which may cause dysfunction of the circulatory, respiratory, and digestive systems. In severe cases, you often need to seek medical attention.

How can we effectively sober up?

In fact, a more feasible method is to drink a lot of water. In addition, there is a more convenient control method, which is to eat some food at any time before and during drinking. If you drink on an empty stomach, the absorption efficiency of alcohol will be greatly increased, but if you drink with food, it can slightly reduce the absorption of alcohol.

In addition, in order to deal with the drowsy state, some people will try to drink tea, but this is not a good idea. Although the tea polyphenols in tea have a certain liver-protecting effect, theophylline in strong tea can cause blood vessels to constrict, increase blood pressure, and aggravate dehydration.

Have you learned all the knowledge today?

This article was scientifically reviewed by Mou Dan, a first-class middle school teacher at the Experimental School Affiliated to the Haidian District Teachers’ Training School in Beijing.

Source: Science Popularization China