Puhallustestejä

Puhallustestejä, commonly translated as breathalyzer tests or breath tests, are a method used to measure the alcohol concentration in a person's breath. This measurement is often used to determine if an individual is under the influence of alcohol, particularly in contexts related to driving under the influence laws. The device, known as a breathalyzer, works by detecting the presence of ethanol vapor exhaled from the lungs.

The scientific principle behind these tests is based on the fact that when alcohol is consumed, it is absorbed into the bloodstream and then distributed throughout the body, including the lungs. As blood circulates through the lungs, some of the alcohol passes from the blood into the air sacs (alveoli) and is then exhaled. The concentration of alcohol in the exhaled breath is directly proportional to the concentration of alcohol in the blood, a relationship established by Henry's Law.

There are several types of breathalyzer technology. Electrochemical fuel cell sensors are widely used as they are highly specific to ethanol and are less affected by environmental factors than older technologies like semiconductor sensors. Infrared spectroscopy is another method that can be employed to detect alcohol. For legal purposes, breathalyzer tests must be conducted using calibrated and approved devices, and the procedures for their use are strictly regulated to ensure accuracy and reliability.

In many jurisdictions, a positive result from a breathalyzer test can be used as evidence in legal proceedings. These tests are a common tool for law enforcement to enforce drinking and driving laws and to promote road safety. Beyond legal enforcement, breathalyzer tests can also be used in medical settings or for personal monitoring.