In a continuous-flow oxygen system, what controls the amount of oxygen delivered to a mask?

In a continuous-flow oxygen system, the amount of oxygen delivered to a mask is controlled by a calibrated orifice. This is a critical component of the system as it regulates the flow of oxygen based on its design specifications, which dictate how much oxygen can pass through at any given time.

The calibrated orifice functions by creating a specific pressure differential that facilitates a steady and consistent flow of oxygen to the user. This is particularly important in aviation, where maintaining appropriate oxygen levels can be crucial for ensuring pilot and passenger safety at high altitudes, where oxygen levels are significantly lower.

While other methods exist for oxygen control, such as valves or electronic systems, the use of a calibrated orifice is a common standard in many medical and aviation oxygen delivery systems because it is simple to maintain and provides reliable performance under varying conditions.