How and when do the photoluminescent floor level lighting charge?

The photoluminescent floor level lighting is designed to ensure visibility and safety in emergency situations, particularly during evacuations. The correct approach for charging this lighting system involves bright cabin lights, which energize the photoluminescent material effectively.

This charging process is done before the first flight, allowing the lighting to be fully charged and ready for use throughout the flight. Specifically, ensuring the cabin lights are turned to bright for an adequate duration—15 minutes—is crucial. This duration allows the photoluminescent material to absorb sufficient light energy to glow in the dark, providing essential illumination for passengers and crew during an emergency.

The other options suggest incorrect charging conditions, such as dim or low level cabin lights, which would not sufficiently charge the photoluminescent system to provide the necessary brightness for safety during an evacuation. Additionally, the idea of charging only at night or during boarding would not ensure the system is prepared and functional for the duration of all flights. By emphasizing the need for bright lighting during initial charging, this option correctly outlines the operational standards for ensuring effective safety features on board.