What must be ensured regarding the Photoluminescent Emergency Marking (PEM) in the cabin?

The correct answer highlights the importance of maintaining safety standards within the cabin environment. It is vital to ensure that any missing Photoluminescent Emergency Markings (PEMs) on walls or ceilings are reported. These markings are crucial for passenger safety, especially in low visibility situations such as during an emergency evacuation. Functioning PEMs provide essential guidance to exits and help direct passengers to safety, making it imperative to promptly address any deficiencies.

The protocol surrounding PEMs involves regular checks to ensure all safety markers are intact and visible, contributing to the overall safety management of the aircraft. This proactive approach allows for timely maintenance and ensures that safety measures meet regulatory requirements.

Other options do not align with critical safety protocols. For instance, switching off cabin lights during takeoff could hinder visibility rather than enhance safety, and the requirement for crew movement and seating is governed by other safety protocols that emphasize situational awareness and passenger assistance rather than enforced standing. Additionally, damaged PEMs should be reported rather than suggested to be present, as damaged safety features could lead to confusion and potentially compromise passenger safety during emergencies.