Zero Stability BAC reading
"absolutely no alcohol detected", a three-digit breathalyser may give you more information, but it does not necessarily make you safer unless it is a higher-quality unit with a better sensor and a reliable calibration program.
A few points about zero stability:
Most consumer breathalysers use either semiconductor sensors or fuel-cell sensors.
Our Andatech and AlcoSense breathalysers uses fuel- cell sensors.
Fuel-cell sensors generally have much better long-term stability and specificity for alcohol.
Semiconductor sensors are more prone to drift and can be affected by temperature, humidity, and other volatile compounds.
Zero drift can occur over time as the sensor ages or becomes contaminated. However, there is no universal direction for the drift.
A unit can drift:
Positive (showing a small reading when true BAC is zero), or
Negative (under-reporting actual alcohol levels).
In practice, manufacturers calibrate instruments to minimize systematic bias, but aging sensors often become less predictable rather than drifting consistently in one direction.
A stable "0.000" display does not necessarily mean the true zero point is perfectly calibrated. Some units apply filtering, averaging, or simply round small values to zero.
For someone who must comply with a zero-BAC requirement, the biggest concern is usually not whether the display shows two or three decimal places, but:
1. The quality of the sensor (fuel-cell vs semiconductor).
2. Calibration frequency.
3. Whether the device has a known accuracy specification near zero.
4. The manufacturer's reputation and calibration support.
For personal breathalysers, depending on budget, we can recommend:
