Where the automatic REX device is a motion sensor, it shall be listed for the purpose and:

When an automatic Request to Exit (REX) device functions as a motion sensor, it is crucial that it is installed in a manner that ensures it only responds to intentional requests for exit. This means that the motion sensor should be calibrated and positioned in such a way that it distinguishes between legitimate movement that requires an exit action and other forms of incidental motion that should not trigger the system.

The focus on intentional requests is essential to ensure security and prevent unauthorized access through the exit points. Devices that are overly sensitive to any type of motion can lead to vulnerabilities in a security system, as they might allow individuals to leave the area when they shouldn't, or may cause unnecessary exits that disrupt normal operations.

The other options describe features or functionalities that may not align with the primary purpose of the automatic REX motion sensor. For instance, permanent installation or supporting manual activation mechanisms could detract from the device's primary automated function. Programming automated access during certain hours pertains more to time-based control than ensuring intentional activation, which is the key consideration for a motion sensor REX device.