About Breathalyzer Machines


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About Breathalyzer Machines

dui breath test

In our role as a DUI Specialist Orange County, our firm often will closely examine the maintenance and calibration of breathalyzers. A breathalyzer is a machine that is used to measure the blood alcohol content (BAC) from a breath sample.

In Orange County DUI arrests, the most common breath testing machine is the Alcosensor IV, soon to be replaced (in October, 2015 and rolling out in a process continuing for months afterwards) by the Alcosensor V.   In Los Angeles DUI cases, the Alcosensor IV, and the Datamaster machines are commonly used.

Breathalyzer is actually a brand name for the original instrument invented by Robert Frank Borkenstein, but most people use it to describe any generic device used to estimate blood alcohol content. Because of the quick and non-invasive nature of the breathalyzer test, it is a useful tool in many situations. Law enforcement are the most well known users of the product, using it to monitor drinking and driving.

Before administering a breathalyzer test however, officers will conduct field sobriety tests if they suspect that a motorist has been driving under the influence of alcohol. This usual involves performing simple physical tasks such as standing on one foot or walking in a direct line. If the member of law enforcement concludes that the motorist has failed one or more of these tests, they can then request that the motorist submit to a breathalyzer test. The results of this test can be used to corroborate the officer’s opinion testimony in order to press charges, or can be used to demonstrate that the driver’s blood alcohol level was higher than the permissible level.

A driver can refuse to take a breathalyzer test, however if they choose to do so their license can be suspended for a period of time. In California refusing to submit to an evidentiary breathalyzer test (as opposed to a preliminary screening device) is considered an offense and the driver can incur a driver’s license penalty for this.

Breathalyzer tests are not infallible though.  A good DUI Defense Attorney will often try to challenge the reliability of the breathalyzer machines themselves by pointing out errors in testing, errors in breath testing, or errors in calibration of the breath testing machine. Every testing machine or testing device must be calibrated periodically to ensure accuracy.

Calibration is the act of checking and adjusting the internal workings of a breathalyzer machine by comparing the results to a known standard of alcohol. Once calibration has been completed by trained lab technicians, a certificate will be given to the law enforcement agency using the machine.

Any failure to complete these calibrations can raise the question of reasonable doubt and lead to an acquittal or dismissal of the DUI charges.

Other factors that can lead to a not guilty verdict in a DUI are that the officer did not administer the test correctly or that the defendant’s blood alcohol level was raised due to biological factors, or interference with the testing device.

In recent years breathalyzer machines have been used to aid in preventing drunk driving. Courts handling a Los Angeles DUI even a first time DUI in Los Angeles County must order a person who is convicted of drunk driving to install an interlock ignition device (IID) in their vehicle. For Orange County DUI cases, this is not required under the law.

For persons convicted of a DUI, an ignition interlock device requires that the driver must breathe into the machine before starting the car. If the driver’s blood alcohol levels are above a preset limit, then the car will not start. Additionally the driver must periodically breathe into the machine to confirm their blood alcohol level, otherwise the car will shut down and the horn and lights will activate.

If you have questions about Breathalyzer Machines, of any kind, we are here to help you.  Please contact us any time for questions or for your free consultation.

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