What is the intoxilyzer? – Several years ago, the State of Texas replaced the Intoxilyzer 5000 EN, the machine law enforcement officers used to conduct breath alcohol tests, with a different version called the Intoxilyzer 9000. The machine is designed to identify different wavelengths of light absorbed from the breath sample to measure for ethyl alcohol.  Inside the device is an optical bench that contains a heated sample chamber, an infrared light source and a pyroelectric detector.  At one end of the sample chamber, the pulsed infrared light source emits infrared light energy that passes through a lens. The detector at the other end measures the amount of energy and converts it into an electrical response.  A microprocessor uses the response to calculate the breath alcohol concentration (BAC) of the sample.

The machine analyzes a breath sample in a multi-step process.  First, an air blank is pushed through to ensure the sample chamber is clear of any interfering molecules.  Then a breath sample is introduced into the device.  Next, a known quantity of ethyl alcohol is analyzed to provide the machine an example of what it is looking for in the breath sample.  The microprocessor compares the numbers the device measured, and the difference is printed as an actual BAC test result.  The greater the difference between the values the higher the BAC reading.

Another way to explain the process is to think about a flashlight with a paper towel roll placed in front of it.  At the other end is a piece of metal with different colored windows connected to a computer.  If nothing is inside the tube, the light goes directly through to the color plate.  If we put cotton balls inside the tube, they block some of the light and not all of it makes it to the end.  The cotton balls represent alcohol molecules and the flashlight with the color plate represents the pulsed infrared light source and detector.

Some of the features of the Intoxilyzer 9000 include the following:

-Easy to use one-button operation.

-It is able to analyze a sample by using multiple infrared wavelengths.

-Both wet and dry ethanol gas standards can be equipped for use with the Intoxilyzer 9000.  Texas utilizes the liquid standards.

-There is no need for any type of mechanical chopper in the analytical section because the company changed to a digitally-controlled puled infrared source.

-Multiple communication ports can be accessed on the device. These include audio side ports and easy-access USB ports.

-The Intoxilyzer 9000 can be used for both law enforcement testing and employee testing.

The Intoxilyzer 9000 does have its share of flaws, including the following:

-The Intoxilyzer 9000 is not warranted by the manufacturer as being either reliable or accurate in terms of human testing. It is only warranted to analyze a reference sample solution that has been provided by the manufacturer.

-The device is not able to replicate human lung function in a reliable or accurate manner.

-Infrared light could be blocked in the device thanks in large part to all sorts of various interferences that can exist in an individual’s breath. These can include acetone, ketones, tobacco smoke, and moisture.

-The machine has to be told what ethyl alcohol looks like by using standards that are mixed in the lab.  Slight problems with the standards can have an immense impact on the outcome because of the small amount of substances being measured.

-The tube heater can malfunction over time. If the machine’s tube was not heated properly then particulate/condensation can collect in the tube and make the machine read incorrectly.

Thank you for visiting Collin Evans Law’s blog, a Houston criminal defense law firm. For more information about what is the Intoxilyzer 9000, you may call our office for a free consultation.  Get the information and legal advice you are seeking at (713) 225-0650.