How Does a Breathalyzer Work? Should You Refuse One?

If you are stopped for a suspected DUI, law enforcement may ask you to take a breathalyzer test. But before you decide to submit to a breathalyzer test or refuse one, you should know how the process works and know your rights.  


How a Breathalyzer Works  


A Portable Breath Test (PBT) measures your breath’s deep lung alcohol concentration by blowing into the device for several seconds. The small, hand-held device is typically used in the field. After exhaling for several seconds, the officer will depress a button that captures the deep lung air. This test is believed to give a more accurate sample than a blood alcohol reading. 


Reliability of Breathalyzer Tests 


Several factors can affect the reliability of a breathalyzer reading: 


  • Breathalyzers must be calibrated frequently to make sure the fuel cell reads correctly. The fuel cells can degrade and become unreliable over time. 
  • Law enforcement needs to wait 15 minutes from first approaching a subject before they can obtain a breath sample. It’s understood that it takes about 15 minutes for any potential mouth alcohol, like mouthwash, to dissipate and be absorbed by the body before testing. 


Read More> Factors That Can Influence DUI Breathalyzer Test Results  


Police Station Breathalyzer Tests 


Law enforcement uses a different breathalyzer at police stations. The larger device is a more advanced machine that measures deep lung air with infrared spectroscopy. Any alcohol molecules in the breath sample will absorb radiation from the infrared light. This breathalyzer measures how much infrared radiation reaches the other side of the chamber. The amount subtracted from the original number measures how many alcohol molecules are in the sample. 


Never Try to Fool a Police Station Breathalyzer 


The more advanced breathalyzer at police stations is highly sophisticated and sensitive, taking human error out of the equation. If one tries to alter their air sample by blocking the breathalyzer’s straw, the machine will fail to signal a proper breath sample. It also detects when deep lung air is achieved and records the sample itself rather than an officer pressing a button like the PBT.  


Should You Take a Breathalyzer Test? 


Under Florida’s Implied Consent Law, any person refusing a breathalyzer test is subject to a mandatory license suspension. The first refusal offense will result in a one-year license suspension. A second or third offense will result in 18 months of license suspension and possible jail time. 


What Are the Advantages Of Refusing a Breath Test?  


Even if you provide a breath test and your breath alcohol is below the .08 limit, you could still be charged with a DUI. When an officer arrests someone they suspect of being under the influence of alcohol or drugs, they are not likely to “unarrest” that person. 


Refusing a breathalyzer test will result in less evidence against you, particularly if you have a criminal jury trial. The prosecution will only have the field sobriety test and contention of erratic driving as evidence, rather than a potential blood alcohol level over the legal limit. But refusing to take the breathalyzer test will not guarantee you will avoid a DUI conviction.  



Accused of DUI?  


If you are accused of a DUI, you must know your rights. If it is your first DUI in Tampa, you may be eligible for a diversion program. The attorneys at Stechschulte Nell Law are prepared to pick up the phone and work on restoring your license as soon as possible. There is only a 10-day period to regain your license after a DUI arrest, so contact our Tampa DUI lawyers today.  

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