When calibrating a helium analyzer, what reading should the device display when exposed to ambient room air?

When calibrating a helium analyzer, the device should ideally display a reading of 0% when exposed to ambient room air. This is because ambient room air is composed primarily of nitrogen (approximately 78%) and oxygen (approximately 21%), with only a very small percentage of other gases including argon, carbon dioxide, and trace gases. In normal atmospheric conditions, helium is present in such a minimal concentration (around 0.00052% by volume) that it is effectively considered absent for the purpose of calibration. Therefore, the analyzer should correctly indicate that there is no helium present in ambient air, which corresponds to a reading of 0%. This ensures that the analyzer is properly calibrated to detect the presence of helium accurately in other samples.