4 Difference Between Breathalyzer And Blood Alcohol Test

November 17, 2022

Share This Article


Many knows that there are a lot of health complications after drinking too much alcohol. Road and machinery accident or being taken advantage are amongst bad scenario that can happened to those who are drunk and wasted. But how would you know you are drunk and unfit to perform any activities such as driving and handling machinery?

Sometimes, police will conduct a roadblock to prevent drunk driver from causing casualty on road. How did they determine whether the driver’s alcohol level is within allowable level or not? They will do a test to check Blood Alcohol concentration by using either Alcohol Breathalyzer or draw your blood for Blood alcohol Test.

Is there any difference between both technique? Let’s find out 4 differences between Breathalyzer and blood alcohol test.

What Is A Breathalyzer Test?


A Breathalyzer is a device that is used to determine your blood alcohol concentration (BAC). The police will usually perform several tests to determine that you are drunk while driving.

If the officer is suspicious of you after performing the tests, they will instruct you to blow through a breathalyzer device. After blowing on it, the screening device will provide you with 4 result categories as below:

  • Zero – You do not have any trace of alcohol in your blood, therefore you are safe.
  • Pass – You have a small percentage of alcohol in your blood, but are still below the limit.
  • Warn – You have 0.03 percent of alcohol in your blood. You are buzzed, but able to be in control.
  • Fail – You have 0.05 – 0.40 percent of alcohol in your blood. You will be detained by the police for further action.

Now that you know the basic information regarding the breathalyzer, what about a blood alcohol test? These are 3 main differences:

1. BAC Measurement Through Breath Vs Blood

As both of the names imply, a breathalyzer test is performed by blowing air inside the device. How it works is that they will take a sample of the ambient air as a blank check, then followed by a check sample of air/ethanol standard.

Meanwhile, a blood alcohol test is conducted by taking a blood sample of the participant. The doctor will draw the participant’s blood, and send them to be tested in the laboratory.

2. Accuracy Rate

Do both types of tests will yield the same results? The answer is no, because both of it has a different accuracy rate. For breathalysers, the accuracy rate could be offset up to 15 percent. To know about the factors of these inaccuracy, you may click on this link. (Link 3rd article)

However, the case is different when it comes to blood alcohol test. The result can be 100% accurate, but with the right conditions; blood alcohol test using alcohol test kit should be taken within 6-12 hours after your last drink.

3. Blood Tests Are Less Prone To Environmental Factors

If we compare these two tests, a blood alcohol test is more accurate and less susceptible to environmental factors that could influence the test results.

However, for breathalyzer, it relies on the alcohol in the blood that transfers through the air via. exhalation from your lungs, which makes it more susceptible to environmental factors such as using medications like an inhaler or cough syrup.

4. Different Result Duration

The biggest difference that you should know is a breathalyser will take fewer result duration compared to blood alcohol test. A breath test may yield results within 12 hours, while blood alcohol test takes longer time, which is up to 4 to 6 weeks.

Now that you know these 4 differences between breathalyser and blood alcohol test, you can choose which type of alcohol test that you prefer. If you are planning to buy a breathalyser, you can click on this link or contact us.