Breathalyzer calibration standards are guidelines and procedures that ensure a breathalyzer device will accurately and reliably measure a driver’s blood alcohol concentration (BAC). Regular calibration and maintenance ensure the device operates properly and up to legal standards. When a breathalyzer is not calibrated properly, it can give false results that can affect DUI cases and could result in wrongful convictions or dismissals.

In this article, we will define breathalyzer calibration standards, explain why they are important, and outline the procedures that ensure device accuracy.

Key Takeaways

• Breathalyzer calibration standards are guidelines that ensure that breathalyzer devices give accurate BAC readings.
• It’s important for breathalyzers to yield accurate results so that courts can admit and use them as evidence in DUI cases.
• Calibration of devices must be done at scheduled intervals using certified equipment and procedures.
• If it is not calibrated or calibrated improperly, the machine can give false readings, which defense attorneys can use as a defense in DUI cases. 

What Are Breathalyzer Calibration Standards?

Breathalyzer calibration standards are the legal regulations regarding how frequently and precisely breathalyzer devices must be tested and maintained to be accurate. These standards are usually established by state laws, the state’s law enforcement agencies and organizations such as the National Highway Traffic Safety Administration (NHTSA).

Breathalyzers must be calibrated regularly to keep them accurate, as sensors drift and environmental conditions and regular wear and tear affect how they work. Failure to regularly calibrate the device may result in unreliable BAC readings that may not only lead to people being wrongly charged with a DUI offense but also acquitted of the offense.

Proper calibration of a breathalyzer is crucial for several reasons, including:

• Accuracy of BAC Readings: A well-calibrated device means that the BAC reading accurately measures the amount of alcohol in a person’s breath, reducing false positives and false negatives.
• Legal Admissibility: Courts accept breathalyzer results as evidence in DUI cases only if proof is given that the device was calibrated according to legal standards.
• Avoiding False Convictions: Poor calibration can mean incorrect BAC readings and, therefore, wrongful DUI charges, fine,s and license suspensions.
• Compliance with Regulations: State-mandated calibration schedules and procedures are required by law enforcement agencies to ensure proper calibration and integrity of DUI enforcement efforts.

Breathalyzer Calibration Procedures

Calibration procedures vary by state and device type, but they generally follow these standard steps:

1. Routine Calibration Checks: Calibration is required for most breathalyzers every 30 – 60 days or after a set number of uses. Maintenance and recalibration typically all follow the set schedule of law enforcement agencies.
2. Use of Calibration Gas: Accuracy is tested using certified calibration gas of a known alcohol concentration. The device is then adjusted to make sure it measures the correct known concentration.
3. Device Inspection: Technicians inspect the breathalyzer for any physical damage or sensor problems that could affect the accuracy. Over time, internal components like fuel cells or infrared sensors may have to be replaced.
4. Record-Keeping: All calibration records must be carefully kept up to date, recording dates, results, and any adjustments made to the device. These records can be used to verify the reliability of the device in court.

In some DUI cases, breath alcohol calibration records are scrutinized to make sure the device was functioning properly at the time of the test.  Defense attorneys may challenge breathalyzer results based on:

• Lack of proper calibration records
• Incorrect calibration procedures
• External factors
• Operator errors

If calibration issues are identified, DUI charges may be reduced or dismissed.

Bottom Line

Calibration standards for breathalyzers are critical to ensure that the measurement of BAC in DUI cases is accurate and reliable. Failure, error, negligence, or misconduct in the calibration and maintenance of breathalyzers has the potential to lead to wrongful convictions and to destroy confidence in how evidentiary processes are conducted by law enforcement.

If you are being charged with a DUI and you suspect the breathalyzer used may not have been appropriately calibrated, consider seeking the counsel of a DUI attorney with experience in dealing with breathalyzer errors.