H2 Gas Detector Calibration Issue

Does anyone here have experience with the ATO Hydrogen H2 detector (0–40,000ppm range)? I’m trying to determine its accuracy and repeatability. Also, if I want to detect Hydrogen around 27,500ppm, how many calibration points would you recommend? Lastly, is the calibration gas usually a mixture of Hydrogen in the air?
Thanks!

Knable wrote:
1. The accuracy of the H2 detector is ±3% FS, and the repeatability is 1%.
2. For your target range (27,500ppm), one calibration point is sufficient. You can use calibration gas between 25,000–30,000ppm for this.
3. Yes, the calibration gas is typically a mixture of Hydrogen in air, as the sensor requires the presence of Oxygen to measure Hydrogen.

Knable wrote:
From my experience, I'd recommend at least two calibration points for better accuracy, especially when measuring near the upper range of the detector. For 27,500 ppm, you might consider calibrating at both 20,000 ppm and 30,000 ppm. This helps ensure linearity across your target range.