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Learn More About Breath Tests

How Do Breathalyzers Work?

Can a person's breath really be used to measure blood alcohol level?

Some say no. However, the police administering the breathalyzer are using the machine to determine your blood alcohol by measuring the amount of alcohol in your breath. When alcohol is consumed, it isn't digested right away; a portion of the alcohol you consumed makes it through the lungs. Some of the alcohol you drink passes through the membranes of your lungs and into the actual air. The air in your lungs, therefore, captures a small portion of the alcohol in your body.

…the ratio of alcohol in your breath to the alcohol in your blood is 2100 to 1.

When you blow into a breathalyzer, the machine is attempting to calculate the level of alcohol in the breath you expel, to attempt to measure what your actual blood alcohol level is. It has been concluded that the ratio of alcohol in your breath to the alcohol in your blood is 2100 to 1. This means that 2100 milliliters of breath will contain the same amount of alcohol as 1 milliliter of your blood.

By doing the math, the machine spits out a number that attempts to show your actual blood alcohol level. If your blood alcohol level is .08 grams of alcohol for every 100 milliliters of your blood, you may be considered an intoxicated driver by the arresting officer.

There are many myths and pieces of advice about breathalyzer tests to consider. Read through the situations in the list below to determine your best course of action moving forward.

Challenging a Breathalyzer Test

Many factors affect the accuracy of a breathalyzer. Some are based on assumptions and some are based on science. It should be your own unique body chemistry that is challenged to determine your Blood alcohol content.

Refusing a Breathalyzer Test

If you refuse a breath test, then a report of refusal form is sent to the Secretary of State stating such. You will have only fourteen days from the day of your alleged refusal to contest the allegation. In the event of a refusal, you must fight this every step of the way.
Learn more about how the reason for which you were pulled over, and how it can help your case.

DUI Driving Patterns

It's important to look into and all reason to challenge the reason an officer stopped you. Doing so will open up many legal opportunities for you in court. Have an attorney on your side with the right knowledge.


Many impressions of your case begin before the officer even pulls you over. Unsafe driving or speeding may be the reason the officer suspects something in the first place. A good defense attorney can use this bias to show that the officer was predisposed to arrest you.
Inaccurate breathalyzer tests are ideal for your case. Visit this page to learn more.

Breath Test Errors

Most breathalyzers contain some margin of error. It could mean the difference between guilty and not. Investigating into these inaccuracies and errors are very real possibilities, since many breath test results are not accurate enough to be relied upon in court.

Your OWI/ Criminal Defense Lawyer

Being arrested for drunk driving (OWI) or any criminal offense can be very scary; but bouncing back better than ever starts with finding the right attorney - a lawyer who understands you and the charge you're facing. Having handled countless cases across Michigan has earned me the reputation, expertise, and understanding to navigate your case the right way. As as solo practitioner, your case is my top priority. It will remain my top priority as I work every angle to accomplish our mutual goals of keeping your record clean, avoiding jail, and maintaining your driving privileges. Work and family are top priorities; everything I do for you is an extension of the many responsibilities you have and the people who rely on you. Call today for the peace of mind of consulting a legal expert best suited to keeping your life moving in the right direction.