Which factor is crucial in maintaining measurement accuracy during breath testing?

Maintaining measurement accuracy during breath testing is heavily reliant on consistent calibration. Calibration ensures that the Intoxilyzer 9000 is precisely measuring the alcohol content in the breath samples. This process involves regularly adjusting the instrument to standard reference samples to ensure it provides accurate and reliable results.

If the device is not properly calibrated, even slight deviations can lead to incorrect blood alcohol concentration (BAC) readings, which can have significant legal implications. Factors such as environmental conditions can affect the performance of the device, but consistent calibration directly targets the core functionality of the equipment, ensuring that it performs according to its specified standards regardless of external influences.

While other factors like environmental conditions or humidity may have some impact on the test results, they do not address the fundamental requirement of the device's reliability, which calibration specifically targets.