At what pressure does the safety outflow valve open if the cockpit differential pressure exceeds it?

The safety outflow valve is designed to regulate the cabin pressure within an aircraft, ensuring that it does not exceed a certain value for operational safety and passenger comfort. When cockpit differential pressure rises above this predefined limit, the safety outflow valve activates to prevent structural damage and maintain a safe environment.

The specific opening pressure for the safety outflow valve is generally standardized, and in this context, that pressure is set at 4.0 psi. This means that once the pressure inside the cockpit exceeds 4.0 psi compared to the atmospheric pressure outside, the valve will open to release pressure and stabilize the cabin environment. This value is crucial for pilots and engineers to understand, as it helps them manage pressure and ensure the safety systems are functioning as intended. The other values listed, while potential options, do not align with the established safety parameters for cabin pressure management.