Breathalyzer Calibration



If you require calibration or other maintenance/repair services not covered under warranty, please complete and follow the instructions on the Service Request Form.

About breathalyzer calibration

Just like a guitar requires regular tuning or a clock needs to be reset, all breathalyzer devices – whether for personal or professional use – require calibration to ensure accuracy.

Like many devices we use daily, breathalyzers will gradually begin displaying inaccurate results if not properly maintained on a regular basis.

What is calibration and why is it important?

Breathalyzer calibration is the process of checking and adjusting the sensor within the breathalyzer to ensure it displays an accurate reading.

Without calibration, the sensor will begin displaying inaccurate and inconsistent results and eventually become damaged.

Calibration ensures that the sensor is in great working condition, results will be accurate and accuracy will be consistent. Calibration also ensures that all components of the breathalyzer are working properly, free of defects and are well maintained, extending the overall lifespan of the breathalyzer device.

In addition, damage to the sensor caused by delaying calibration is not covered under the device warranty.

How often does my device need calibration?

Depending on the type of device and the purpose, recommended calibration times vary. Most breathalyzers with a display screen will display CAL when the tester is due for calibration. For breathalyzers with LED lights, refer to your user manual to see how calibration is required is displayed.

In general, a personal breathalyzer device will indicate that calibration is required after 1 year or 5000 tests; breathalyzers for law enforcement should be calibrated once per month.

Calibration is needed sooner if your breathalyzer is providing inconsistent results, results that are abnormally high or low, or the device is not displaying results at all.

How much does calibration cost?

For price information for our calibration services, contact Customer Service at

How are breathalyzers calibrated?

There are 2 methods for calibrating breathalyzers: breath alcohol simulator and compressed gas standard.

When we receive your breathalyzer for calibration, we will determine which calibration method is most suitable for your device. No matter which calibration method is used, a trained lab technician must perform the calibration process.

To learn more about the different calibration methods click here.

Why choose ACS for calibration services?

With 40 years of experience producing and maintaining breath alcohol testing products, we know how to keep your device working to its greatest potential. When your breathalyzer requires calibration, simply send it to ACS and we’ll calibrate it and ensure that all components are in optimal condition.

Alternatively, you can enroll in the ACS Product Protection Plan which includes 4 breathalyzer calibrations per year as well as many other services which ensure your device is perfectly maintained and kept in great working condition.

With our experience and expertise creating industry-leading breath alcohol testing technology, there’s no better way to ensure that your breathalyzer is working accurately and in optimal condition.