Drug & Alcohol Breath Testing: The Science Behind Drug Testing
Overconsumption of alcohol or drugs can have serious health effects. It may even lead to unfortunate events, especially if a person is driving or riding a vehicle under the same influence. Hence, breath testing is crucial, and these are carried out by authorities at traffic stops and checkpoints to ensure safety and avoid mis happenings, especially alcohol breath testing and Urine Drug Test.
Are you wondering what an alcohol and drug breath test is or how it works? Keep reading this detailed article to learn about the science behind the alcohol breath test.
What Is A Breath Alcohol Test?
If someone consumes alcohol, it directly goes into the stomach and small intestine and gets absorbed into the blood quickly. One can measure the Blood Alcohol Concentration or BAC of a person within minutes after they consume alcohol; however, the BAC reaches its peak level usually after an hour of drinking. The testing of BAC is popularly called the Breath Alcohol Test.
Around 90 percent of the alcohol in the body gets broken down by the liver. The rest of it is eliminated through breath or excreted through urine. The screening or testing devices measure the alcohol amount in the breath as part of the BAC. Numerous reputed organizations offer a program for a breath alcohol test as prescribed by the government or transportation authorities.
These devices contain a disposable mouthpiece where a person must blow with a decent amount of pressure. The entire testing process takes around a minute, after which the device records the result. The results are displayed in four categories, namely, “zero,” “pass,” “warn,” and “fail,” and a failed test requires the person to undergo another evidential test at the police station.
How Does The Drug And Alcohol Test Work?
The testing process follows specific rigid guidelines. A diagnostic scan is carried out before the breath sample is taken from the person, and a blank test is performed with ambient air to calibrate the device. The blank reading should be 0.00. Once calibration is done, the person is instructed to blow hard into the device for a couple of seconds.
The breath testing devices used in evidential tests mainly consist of a fuel cell like other screening devices or the infrared cell. An infrared cell uses infrared energy directed towards the sample, and unabsorbed energy is detected on the other side. The concentration of ethanol is directly proportional to the absorption of the infrared waves; hence more concentration results in more absorption.
The test accuracy depends on whether the breath sample is deep lung or the alveolar air. The results can also vary depending on how large the lungs of the person being tested are. When a person breathes out into the device, the expired air is monitored continuously with the help of the infrared cell. Initially, there was a rise in the ethanol concentration. Still, as the expiration continues, the level of ethanol stabilizes slowly, and at that time, the breath sample is analyzed, and reading is obtained.
There are chances that a rapid peak is observed for the ethanol concentration during the evidential test. If such a rapid peak is monitored by the infrared fuel cell, then the test must be aborted, and instead, blood samples are taken. These testing devices may also register some interfering substances sometimes, and in that case, the test process is aborted, and a sample of blood is required.
What Is The Breathalyzer?
The breathalyzer was invented in 1954, and it is the most used portable device to test breath alcohol content. The alcohol test measures the blood ethanol content. This device comprises a negatively charged electrode called the anode and a positively charged electrode called the cathode.
When a person breathes air into the breathalyzer, ethanol in their breath reacts with water present in the air at the anode and gets oxidized to give acetic acid. The oxygen from air undergoes reduction to form water at the cathode. These reactions result in electrical current production among the electrodes proportional to the amount of ethanol present in the breath.
What Do The Government Regulations Say?
The BAC of an adult driver cannot be legally over 0.08 percent anywhere in the United States. If a person has a BAC of 0.08 or more, they need to undergo an evidential breath test at the police station. When it comes to drivers under the age of 21, every state has a “zero tolerance” law. Any underage person driving should have no detectable amount of alcohol in their breath.
The National Highway Traffic Safety Administration sets the BAC limits set at 0.08 percent as prevalent studies show that consumption of alcohol can impair all driving-related skills significantly at that level. The alcohol content present in a person’s breath and how long it persists is dependent on several factors, including weight, sex, amount of alcohol consumed, and the last meal.
Conclusion
The alcohol breath test has become crucial in ensuring a safe commute for everyone and avoiding any kind of hazard or traffic offense. Even though these tests look and sound pretty simple, the science is quite complex and interesting. This article offers a detailed insight into the basic concept of alcohol breath testing and how it is carried out.
Thank you,
Glenda, Charlie and David Cates
