Definition
A breath alcohol test determines how much alcohol is in your blood by measuring the amount of alcohol in the air you breathe out (exhale).
Alternative Names
Alcohol test – breath
How the test is performed
There are various brands of breath alcohol tests. Each one uses a different method to test the level of alcohol in the breath. The machine may be electronic or manual.
One common manual tester requires you to blow up a balloon in one continuous breath until it is full, then release the air into a glass tube. The tube is filled with bands of yellow crystals. The bands in the tube change colors (from yellow to green), depending on the alcohol content. Carefully read the instructions before using the test to make sure you get an accurate result.
If an electronic alcohol meter is used, follow the instructions that come with the meter.
How to prepare for the test
Wait 15 minutes after drinking an alcoholic beverage and 1 minute after smoking before starting the test.
How the test will feel
There is no discomfort.
Why the test is performed
When you drink alcohol, the amount of alcohol in your blood goes up. This is called your blood-alcohol level.
When the amount of alcohol in the blood reaches 0.02 – 0.03%, you may feel a relaxing “high.”
When that percentage reaches 0.05 – 0.10%, you have reduced muscular coordination, a longer reaction time, and impaired judgment.
Driving and operating machineryunder the influence of alcohol is dangerous. A person with an alcohol level of 0.08% and above is considered legally intoxicated (drunk) in most states. (Some states have lower levels than others.)
The alcohol content of exhaled air accurately reflects the alcohol content of the blood.
Normal Values
Normal is when the blood alcohol levels are not elevated.
What abnormal results mean
When one band is green, it means that the blood-alcohol level is 0.05% or lower. Two green bands mean levels of 0.05% to 0.10%. Three green bands indicate levels between 0.10% and 0.15%.
What the risks are
There are no risks.
Special considerations
The test does not take into account the driving abilities of the test subject. Driving abilities vary among people with the same blood-alcohol levels. Some people with blood-alcohol levels below 0.05% may not be able to safely drive. For occasional drinkers, judgment problems occur at blood-alcohol levels of just 0.02%.
The breath alcohol test helps you to know how much alcohol it takes to raise the blood-alcohol level to a dangerous level. Each persons response to alcohol varies. The test may help you make better decisions about driving after drinking.
On New Year’s eve in 1938, the first practically successful machine for testing blood alcohol content in humans by breath analysis was put into use by the police in Indianapolis. Dubbed the drunkometer, it paved the way for better breath analysers as a means to tackle drunk driving. A.S.Ganesh breathes some life into this story…
If you are reading this on the last day of the year, you know what will happen in a few hours. For there’s a party atmosphere generally during New Year’s eve as everyone bids goodbye to the year that has passed, welcoming the new one with gusto.
While the revelry has come to be accepted as part of the celebrations, what is unacceptable is if one has a drink too many, getting way too intoxicated in the process. Worse still, if the said individual then takes to driving, they not only put their own lives at peril, but also that of others on the road.
Need for breath analysers
Breath analysers were invented to control and curb this. One of the earliest such instruments, developed by Rolla N. Harger, was called as the drunkometer. It went on to become the first practical machine to successfully test blood alcohol levels in human beings.
Born in 1890, Harger graduated from the Yale University and was hired as an associate professor at Indiana University School of Medicine. Harger went on to teach biochemistry and toxicology from 1922-1960 and also headed the school’s department of biochemistry and pharmacology from 1933-1956.
No effective solution
Harger set out to work on his breath analyser in the 1930s and received his patent in 1936. Even though the idea of testing blood alcohol levels had existed for centuries, there hadn’t been any effective means to achieve the same. Direct testing of blood and urine samples were effective, but they were cumbersome, costly and were also totally useless when trying to prevent the trouble before it took place. Harger’s drunkometer looked to fill in this gap.