What pressure range should the emergency oxygen system display during preflight?

The emergency oxygen system should display a pressure range of 1800-2500 psi during preflight checks. This range is critical because it ensures that the system is adequately pressurized and ready for use in an emergency situation where supplemental oxygen is necessary. If the pressure is below 1800 psi, it may indicate that the oxygen bottle is underfilled or has a malfunction, which could result in insufficient oxygen supply when needed. Conversely, the upper limit of 2500 psi ensures that the system is operational within safe limits, preventing any risk of over-pressurization that could potentially damage the system or make it unsafe to operate. Ensuring the pressure falls within this specified range is a key part of preflight safety checks and readiness for emergency scenarios in flight operations.