A Breathalyzer's Function Explained

A Breathalyzer's Function Explained

In order to explain how breathalyzers function, we need to take into consideration what exactly it is they measure. Some may be familiar with the term blood alcohol level and are vaguely familiar with legal stats along the lines of 0.08 or .10 BAC. BAC refers to Blood Alcohol Concentration which refers to the notion and concept of evaporated alcohol in the breath. The formula to convert the data will center on amount of alcohol in the 2,100 ml of air a person will expel when they breathe out that is combined with the alcohol present in the blood. While a breathalyzer is used to ID the BAC or blood alcohol level, what is really being done is measuring the amount of alcohol present in the breath.
What is the means in which this process will work? We can see how it works through the examination of the way in which the body absorbs alcohol. It is not digested by the stomach. Rather, it will be absorbed through the membranes in the stomach where it will then be transferred into the bloodstream. Upon entering into the bloodstream, most will evaporate but a certain concentration will end up in the lungs. When a person breathes out, this alcohol laced is expelled. Such a ratio of evaporated alcohol in the breath from the lungs will be directly related to the amount of alcohol that is found in the blood. Through a breathalyzer, the breath is joined with a unique chemical solution and the alcohol in the breath which causes a chemical reaction in the fluid.
A traditional breathalyzer contains two separate vials. One vial separates the alcohol from the air and allows the chemical reaction to take place. The other vial remains the same and is part of a photocell system. The system creates an electrical field. The electricity makes a needle move and the amount the operator has to adjust the knob to get the current to rebalance determines the amount of alcohol in the air.
The larger scale full size breathalyzers are the ones designed for use by various law enforcement agencies and entered as reliable evidence in the courts. In addition to these items, there are also smaller scale personal models that can work quite effectively. However, their results are not considered accurate enough for evidence in a court of law. In both cases, depending upon the individual person, lung capacity and additional factors that can impact results, slight variations in testing can be accounted for which gives the person being tested a small amount of leniency.
Breathalyzers are not known to require any maintenance although making sure its supplies are in proper condition so they may continue to function. Mostly all breathalyzers employ a mouthpiece which is commonly a small tube in which the subject needs to breathe into for about 2 - 4 seconds. Such items are inexpensive and commonly easily replaced. The two vials may require an additional solution in order to be calibrated properly but this is fine. For those involved in legal proceedings with the devices, extended maintenance and proper training is needed.
To summarize, the breathalyzer collects a person's breath, which is laced with a consistent amount of alcohol to air which correlates to the amount of alcohol in the bloodstream which is the legal standard for determining intoxication. The air enters one vial in which the chemical reaction occurs, affecting the photo cell and electrical charge. The measurement of alcohol is determined by the displacement in the electrical field.