How Does A Breath Test For Alcohol Work?

 Many people consume alcohol, but most don’t know that they could fail an alcohol test through their breaths. It doesn’t matter if you’ve eaten or drank some water after. An alcohol breath test determines the amount of alcohol in the air you exhale. 

The device uses this measurement to calculate the amount of alcohol in your blood. Your BAC, or blood alcohol content, is that amount. However, alcohol testing with breath analyzers is entirely accurate. Police use these tests to determine how much alcohol is present in a person’s blood. Read on as we discuss how an alcohol breath test works. 

Breath Analyzers 

The more alcohol you drink, the more slowly you may become, and there is a chance that you don’t make good decisions. Thus, making driving dangerous. Only a few states allow people under the age of 21 to drive if they have a blood alcohol content (BAC) of more than 0.08. 

However, if you drive recklessly or get in an accident, the police in your area may think you’re driving under the influence of alcohol. Then, they use a Breathalyzer right at the scene of an accident or on the side of the road. 

A breathalyzer is the most popular portable device for measuring breath alcohol concentration. Alcohol breathing- test devices determine the amount of alcohol in a person’s breath. They also figure out how much alcohol is in their blood, called blood alcohol level. 

How Does A Breath Test For Alcohol Work? 

Because alcohol is a very flammable chemical, its vapors begin to mix with your breath. The more intense the vapors are, the more they reach the bloodstream. Breathalyzers can detect these fumes when you exhale them. 

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When someone drinks alcohol, it goes into their stomach and small intestines. Then, it gets absorbed into their bloodstream and goes into their body. The BAC of a person who has consumed an alcoholic beverage can be determined within minutes. 

About an hour after drinking, your blood alcohol content (BAC) will be at its peak. The liver breaks down around 90% of the alcohol we drink; urine and breath remove the rest. Then, the breath-testing device calculates the BAC based on the amount of alcohol in the breath. 

However, the three main types of breathalyzers work differently, but they all have a sample chamber and a mouthpiece. Let us discuss how each device works. 

Semi-Conductor Breathalyzer 

A semiconductor sensor uses a tin-oxide material to oxidize alcohol electronically. The device performs a redox reaction by combining water, alcohol, and acetic acid. Then, it measures the current generated. 

It tells you how much alcohol the person puts into their breath by looking at the measured current. Compared to fuel cell breathalyzers, these types are less expensive and have less energy. They are also less accurate than those that fuel cells. 

Fuel Cell Breathalyzer 

Fuel cell breathalyzers work by oxidizing the alcohol in a breath sample with chemicals. Then, they exploit the oxidation process to generate an electric current, and higher alcohol means more electric current. Fuel cell breathalyzers use a permeable acid-electrolyte between two platinum electrodes. 

After exhaling, platinum combines with the alcohol in the air to form acetic acid, electrons, and protons.  

The electrons pass through a wire from the platinum electrode to an electrical current meter. Protons must go through the fuel cell’s lower part to produce water—the electrical current increases with oxidized alcohol content. Then, the microcontroller calculates the blood alcohol content. 

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Spectrophotometer Breathalyzers 

This device uses infrared spectroscopy to determine molecules, depending on how they absorb the IR light. A lamp emits an infrared beam that passes through a sample chamber. It focuses on a filter wheel that rotates around. The filter wheel has band filters that match the wavelengths of ethanol’s internal bonds. 

Each filter has a photocell that turns the light that passes through it into an electric current. You can read a voltage from this current to determine the BAC. These units are evidentiary because they use the best sensor of all alcohol testers and are very good at getting the right results.  

Factors Affecting Blood Alcohol Content 

  • Gender: Alcohol has different effects on men and women. Men have more stomach enzymes that aid in the breakdown of alcohol, so they process it more quickly. Women have less water and more fat than men. Also, hormonal imbalance can affect women’s BAC. 
  • Amount of food consumed: Alcohol will be processed more slowly if you consume high-protein foods. 
  • Weight: Your weight depends on the amount of water in your body. So, the amount of water in your body depends on how much the alcohol in your body gets diluted. 

How to Get an Accurate Reading from a Breathalyzer 

  • Use the breathalyzer when your temperature is average. 
  • Ensure that your breath is normal before using it. 
  • Calibrate your device every six to twelve months. 
  • If you’ve just donated blood, you should allow a broader range of blood tests. 
  • When the breath analyzer is not in use, please keep it in its protective case to keep the sensor from getting dirty. 
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Blood tests were used to determine BAC in the past, but it takes a whole lot of time. So, it isn’t as common anymore. However, the police must identify and detain the drunk drivers. Thus, the invention of Breathalyzers. So, if you blow above the 0.08 percent legal limit, you could be charged with DUI (Driving Under the Influence). 

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