How A Breathalyzer Works

Description :

Breathalyzers were scientifically developed in order to help law enforcement personnel to establish if an individual was driving while impaired due to alcohol. 

How A Breathalyzer Works

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The technical non-invasive devices can ascertain if a driver is drunk so the driven can be removed from the road. Breathalyzers test the concentration of blood alcohol in the driver’s blood.

Blood Alcohol Concentration (BAC)

Years ago the blood alcohol concentration level use to be 0.10. Now most states have a blood alcohol level of 0.08. This limit is also being lowered in some states to 0.05. The American Medical Association has stated that drivers with a level of 0.05 are impaired and should not be driving. A breathalyzer test showing that a driver has a level of 0.15, would prove that per 100 ml of blood, the driver shows 0.15 grams of alcohol present.

Fruit juice or milk is digested but the body does not digest alcohol. It is possible to determine the lever of alcohol by using a person’s breath because it is absorbed by the body. Alcohol goes immediately through the bloodstream and circulates until it is evaporated in the lungs. The molecules of alcohol do not mix with other liquids in the body. Alcohol is volatile in the blood because it is absorbed into the membranes of the mouth, stomach, intestines and throat. Blood passes through the lungs, which allows the alcohol to pass over the lungs air sacs and releases alcohol through the person’s breath. The breath that is being expelled holds the same amount of alcohol that is in the bloodstream. The breathalyzer can then accurately measure the evaporated alcohol through the breath. This is how the blood alcohol concentration is measured accurately for intoxication.

How the Evaporated Alcohol is Measured

Just like a diabetic kit with strips, levels of alcohol will produce chemical reaction on a piece of paper that will make the paper change color. When using a breathalyzer, the breath will travel through a solution. The solution will change color and the police officers will compare that color to the chart for intoxication levels.

The breathalyzer itself has a couple of different devices. There is a straw, which the offender will blow into so the person’s breath comes up from the lungs. The two cylinders with vials contain water, silver nitrate, sulfuric acid and potassium dichromate. A deep breath needs to pull air deep from the lungs.

Once the alcohol is removed from the air, it is absorbed by the liquid solution. The degree of change in color depends on the amount of evaporated alcohol that is in the breath taken from the offender. Only one vial has a chemical reaction. The other vial stays the same. An electrical current is produced which will make a needle on a gage to move. The officer operating the breathalyzer will watch the needle and wait for it to stop moving and then turn a knob to replace the needle to the point where it started. The more the knob has to be turned the higher amount of alcohol is in the solution. This will give the officer the reading level of intoxication.

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