Intoxilyzer 5000EN / Breathalyzer Test in Las Vegas DUI

breathalyzer testAfter an arrest for DUI in the greater Las Vegas area, the arresting officer will typically ask you to submit to a breath test on a machine called the Intoxilyzer 5000EN at the Clark County Detention Center, City of Las Vegas Detention Center, Henderson Detention Center or any other jail facility. Amazingly, the officials in Nevada know very little about the accuracy or reliability of the Intoxilyzer 5000EN.

The Intoxilyzer 5000EN is a machine that collects breath to measure the alcohol concentration in a person’s body. Even if the Intoxilyzer machine is working perfectly when an individual blows into it, the results may not be accurate.

It is necessary to contact an experienced Las Vegas DUI defense lawyer if you had to blow into the Intoxilyzer 5000EN and received a positive test result. Several factors including the calibration of the machine and medical conditions can cause the machine to return an inaccurate reading.

Las Vegas DUI Breath Test Attorney

An experienced Las Vegas DUI attorney can contest the accuracy and reliability of your DUI breath test results by showing flaws in the inspection and calibration process that affect the machine’s margin of error. Even human error in following the Intoxilyzer 5000EN operator’s training manual can call the results into question and possibility lead to their exclusion from the trial.

Contact attorney Joel M. Mann to learn more about ways to fight field sobriety tests such as the breath test results.

Common Challenges Raised in Court Related to the Nevada’s Intoxilyzer 5000EN

During pre-trial motion hearings, the goal in most DUI breath test cases is to request that the judge exclude any mention of the breath test reading at trial.

Common challenges include:

  • Whether the Intoxilyzer 5000EN was properly calibrated, inspected and maintained in strict compliance with Administrative Rules enacted by Nevada’s alcohol testing program which helps determine whether the breath test results are reliable and accurate;
  • Whether the Intoxilyzer was in proper working order or whether glitches were determined in tests taken prior to or after the breath test result in question;
  • Whether the breath test technician was qualified by meeting all training and certification requirements;
  • Whether the breath test in question was properly administered to the subject;
  • Whether the breath test result on the Nevada Intoxilyzer 5000 was within a margin of error of 0.010 which would call into question the finding that the reading was over Nevada’s legal limit of 0.08;
  • Whether the slope detector was acting properly;
  • Whether the instrument needed repairs or was recently repaired;
  • Whether any fail safe flags indicated “INTERFERENT DETECTED” which might indicate the presence of isopropanol or methanol;
  • Whether any fail-safe flag indicated “INTERNAL FAILED” which would indicate that the internal standards measured outside of a 5% tolerance range;
  • Whether the flow sensor properly measures a breath sample of at least 1.1 liters of breath;
  • Whether the subject blew for at least one second;
  • Whether the alcohol concentration slope began to level off;
  • Whether the pressure reached an acceptable range of approximately 1″ of water;
  • Whether the temperature monitoring system on the Intoxilyzer 5000EN was working properly showing that the simulator’s temperature was 34 degrees C (plus or minus 0.5).

Las Vegas DUI Attorney Explains Problems with Intoxilyzer 5000EN

The breath test machine currently used in the Nevada is the Intoxilyzer 5000EN which is manufactured by a company called CMI, Inc., in Owensboro, Kentucky. Many individuals are surprised to learn just how many problems exist with these machines that interfere with obtaining an accurate or reliable test result. Learn why the breath test operators sometimes fail to follow the operator’s manual for the Intoxilyzer 5000EN which compromises the breath test results.

If you submitted to a breath test machine after a DUI arrest in Clark County, Nevada or a surrounding area, then contact an experienced Las Vegas DUI attorney to discuss possible defenses. Just because the machine indicates that you blew over the legal limit does not mean that you will be convicted for DUI. Contact attorney Joel M. Mann to discuss your case and ways to fight the charges to avoid a DUI conviction.

Nevada introduced the new “EN” model which was marketed as being superior because it could measure the volume of the subject’s breath to determine whether the subject was really trying to blow an adequate sample of breath into the machine.

Ways to Challenge the Breath Test Results on the Intoxilyzer 5000 in Nevada

As a preliminary matter, the prosecutor with the District Attorney’s Office must lay a proper foundation before the breath test results can be admitted. Like any other instrument, if you do not maintain and use it correctly, then you cannot trust the result. Therefore, the defense attorney must insist on strict compliance with the rules established by officials with Nevada’s alcohol testing program for the operation of a technically sophisticated and complex measuring instrument.

Without strict compliance of those administrative rules, the instrument cannot be deemed to be accurate or reliable. Thus, the defense must insist that the prosecutor with the District Attorney’s Office make the following showing in each case:

  • The Intoxilyzer 5000EN was properly maintained, inspected and calibrated in strict compliance with Nevada’s Administrative Rules which have a direct bearing o the validity and accuracy of the breath test results;
  • The Intoxilyzer was in proper working order;
  • Its operator was qualified; and
  • The test was properly administered.

When the prosecutor is unable to make such a showing for a particular instrument or a particular breath alcohol reading, then the defense attorney must be prepared to file and litigate the appropriate motions to exclude mention of those breath test results.

Internal Standards on the Intoxilyzer 5000EN

The following internal standards are linked to the predetermined calibration settings and voltage measurements set for the instrument. Changes in the voltage or calibration settings will show up in the Internal Standards. The following standards were established:

  • The .10 standard is 3.40;
  • The .20 standard is 3.47;
  • The .30 standard is 3.80;
  • The .50 standard is 3.52

When the Intoxilyzer 5000EN determines that the internal standards are measuring outside of a 5% tolerance range, then the Intoxilyzer 5000EN will stop the test and flag “INTERNAL FAILED.”

  • 0.100 std range is between 0.095 and 0.105;
  • 0.200 std range is between 0.190 and 0.210;
  • 0.300 std range is between 0.285 and 0.315;
  • 0.400 std range is between 0.380 and 0.420;
  • 0.500 std range is between 0.475 and 0.525.

Internal Printer on the Intoxilyzer 5000EN

The Intoxilyzer 5000EN contains an impact internal printer that needs NCR paper for the print cards. A connection also allows an external printer to be used. When the external printer is set up, the integral printer will automatically be disabled.

Flow Sensor for the Intoxilyzer 5000EN

While previous versions of the Intoxilyzer 5000 contained a pressure switch, the Intoxilyzer 5000EN relies on a flow sensor. The following four (4) minimum requirements must be met before an adequate sample can be analyzed:

  • The subject must blow at least 1.1 liters of air into the tube;
  • The subject must blow continuously for at least one second;
  • The alcohol concentration slope must begin to level off;
  • The pressure must reach approximately 1″ of water.

Intoxilyzer 5000EN’s Standby Mode

Another advantage of the Intoxilyzer 5000EN over the previous models resolves around the standby mode on the Intoxilyzer 5000EN which avoids the need for the instructment to run continuously. The standby mode is intended to cut down on wear and tear on the instrument while still allowing a 30 minute or less warm up time.

Temperature Monitoring on the Intoxilyzer 5000EN

The temperature monitoring feature on the Intoxilyzer 5000EN permits the instrument to confirm the simulator temperature is 34 degrees C (plus or minus 0.5). The testing sequence will be terminated before the calibration check if the temperature is out of range. When the simulator is within range the instrument will notate in the final report that “SIMULATOR TEMPERATURE IN RANGE.”


  • CMI’s Marketing Material on the Intoxilyzer 5000EN – CMI’s website boasts that the Intoxilyzer 5000EN is used by more than 20 states in the United States, enhances the court tests accuracy and reliability of evidential infrared spectrometry for testing of breath alcohol concentrations (BAC).
  • Intoxilyzer 5000EN Specifications from AUSSCO – List of new features on the Intoxilyzer 5000EN including new printer, standby mode, internal modem, less interconnects, thinner cell barrel walls, real time clock and additional serial port that interfaces with the Guth 2100 simulators. Includes information on other Breath Alcohol Testing instruments or breathalyzer manufactured and sold by CMI, Inc., including the Intoxilyzer S-D5, Intoxilyzer 300, Intoxilyzer S-D2, Intoxilyzer 8000, Intoxilyzer 400 PA, Alco Blow, Intoxilyzer 200 / 200D, and the Intoxilyzer 400.
  • FAQ for Intoxilyzer 5000EN Challenges – List of frequently asked questions regarding the settlement between the Commissioner of Public Safety and CMI, Inc., approved by a federal judge on July 16, 2009, for Intoxilyzer 5000EN source code litigation in Minnesota.

Failed DUI Breath Test in Nevada

If you are facing DUI charges in Las Vegas, contact the Law Office of Joel M. Mann for a free legal consultation. Joel Mann is a successful Las Vegas DUI attorney who is dedicated to fighting the breath test results in court and defeating your DUI charges.