Alcohol Breath Testing: How It Works

Alcohol breath testing using a device like a breathalyzer is the most common manner of testing for alcohol today. When a driver is on the side of the road with an officer who has stopped them for a DUI, blood or urine testing is out of the question. This is why highway patrol officers rely on in-car breathalyzer systems (also known as PAS tests) to help judge whether a driver is under the influence of alcohol.

This same type of testing is used when you have an ignition interlock device installed in your vehicle. Your breath sample is measured to determine the amount of alcohol in your system.

Breath testing for alcohol content is an indirect measure of testing for blood alcohol levels. However, it has been widely considered to be scientifically accurate, and, in California, the DUI laws are written to explicitly include both breath alcohol content and blood alcohol content as being legally acceptable.

Breath testing for alcohol concentration is typically performed on one of two types of machines: either an infrared device, or a fuel cell device.

Infrared devices are subject to many criticisms by forensic experts, criminal defense lawyers and DUI practitioners alike. These include interference from molecules that appear to be alcohol, but aren’t; radio frequency interference; discrepancies in sample chamber size; variations in body temperature; and more. This means that you may experience “false positives.” When you blow into the device without alcohol, it may read that you have recently drunk alcohol. Unfortunately, this can cause many issues.

On the other hand, there are other methods of measuring alcohol. Fuel cell devices, like the ignition interlock devices that Smart Start of California uses, address many of the concerns with the other, older technology. Breath alcohol testing with a fuel cell device does not require a sample chamber, or a beam of light to be passed through it. With a fuel cell, your breath sample is passed over an electronic chip. When the sample is read by the device, it is electrochemically oxidized (meaning it is burned up) on the fuel cell itself. This produces an amount of electromagnetic current, which is then measured to equate to a given level of alcohol content.

As a result, fuel cell technology is infinitely more reliable than any other method of breath testing currently available. There are fewer false positives, which means your experience with a Smart Start of California ignition interlock device will be much better than with other ignition interlock providers that may not use fuel cell technology.

You probably already know that California DUI laws have become stricter this year. If you have been required by the court to install an ignition interlock device, contact us anytime, 24 hours a day / 7 days a week. We’ll be happy to set up an appointment and walk you through everything you need to know.

Let Smart Start of California help you get back on the road! Call now: 1-888-289-5669

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