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What You Need to Know About DUI Breathalyzer Tests

What You Need to Know About DUI Breathalyzer Tests

When a police officer stops you for a suspected DUI, they can use a variety of tests to conclude whether you are intoxicated. In this blog, we explain the science behind the common testing methods used by law enforcement in Colorado.

Breath Tests

The following are the 3 most common breathalyzers:

  • Fuel Cell Breathalyzers: With this test, you blow into a chamber on a device that uses an electrochemical process to oxidize any alcohol in your blood. Fuel cell breathalyzers are the most effective testing method, but the devices are expensive. Law enforcement usually keep fuel cell breathalyzers at the station instead of using them for roadside DUIs.
  • Infrared Breathalyzers: Infrared spectroscopy technology can be used to measure your BAC. The spectrophotometer, a piece of equipment in the breathalyzer, can identify ethanol molecules. Police use the level of ethanol in your breath sample to decide if you should be charged with a DUI.
  • Semiconductor Breathalyzers: These breathalyzers measure the resistance of a semiconductor to an electric current. Because alcohol alters the resistance of a semiconductor, the device measures changes from a baseline. If you have a large amount of alcohol in your system, the more noticeable the change will be. Although these test are the most inexpensive to administer, they are also the least accurate.

The following things can impact the reliability of a breathalyzer test:

  • Products like mouthwash and breath fresheners can trigger a high reading because they contain alcohol.
  • An uncalibrated device can produce an invalid test result
  • Fumes from paint, varnish, and other chemicals present in the testing area can affect the results
  • Breath temperature can impact the BAC reading
  • People with diabetes or hypoglycemia have more acetone in their breath, which can create a false positive reading.

Police must adhere to the following guidelines when administering a breathalyzer test:

  • The officer must have received proper training for administering the test for the particular device that is being used to determine if a suspect is intoxicated.
  • Police must observe a suspect for at least 15 minutes before they can begin testing.
  • Breathalyzer devices must be calibrated by a certified technician every 10 days or 150 uses, whichever comes first.

If you have been arrested for DUI, but the arresting officer failed to follow the procedures listed above, the results of your test can be challenged in court.

Speak to a Denver DUI Lawyer

If you are facing DUI charges, you should immediately speak to our lawyers to find out how we can protect your rights. We understand that being arrested can be a frightening experience, which is why our attorneys will stand by your side throughout your entire case. Let us put our skills to work for you today.

Call (720) 619-2676 to request a no-cost consultation with our DUI lawyers in Denver.