Tedlar bags are provided to allow up to approximately 12 minutes of calibration gas flow as standard. Calibration gases may be drawn from two locations - the local pod, and the rear cabin. The local pod bags have capacity for approximately 12 minutes of run time; there is much more space in the rear cabin, so these can optionally be used for longer flights. Calibrations can be configured to run only on crew command, or on a preprogrammed schedule. The state of the valves controlling the calibration sources (and intakes) are logged internally on the analyser. This article was published on 2024-06-25