The latch on an emergency egress door must tolerate a maximum pressure of:

• A. 15 psf
• B. 30 psf
• C. 5 psf
• D. 10 psf

Answer: (A)

In designing emergency egress doors, it's crucial that the latch mechanism can withstand significant force to ensure reliable operation during emergencies. The maximum pressure tolerance of 15 psf (pounds per square foot) for a latch is designed to ensure that the door can be opened easily in stressful situations where panic may occur and people may push against the door.

This specification is typically established to prevent the door from becoming jammed or too difficult to operate, which could lead to dangerous situations where occupants cannot exit quickly. A latch that tolerates 15 psf allows it to remain functional and reliable when subjected to the force of individuals attempting to exit simultaneously, thus adhering to safety standards that promote effective evacuation during emergencies.

In contrast, the other options fall below this threshold, potentially compromising the door's operability in high-pressure scenarios. Such lower tolerances might imply insufficient resilience against sustained force, leading to issues that could hinder safe egress in critical situations. Therefore, the requirement for a latch to bear a maximum pressure of 15 psf is rooted in safety and operational effectiveness.