What are the immediate commands in the event of decompression?

In the event of decompression, the immediate commands prioritize the safety and well-being of the passengers and crew. The correct answer emphasizes the necessity of putting on oxygen masks and securing seat belts.

When decompression occurs, the cabin altitude suddenly increases, and the air pressure drops, which can lead to a lack of oxygen for those onboard. Therefore, the first step is to ensure that all individuals have access to supplemental oxygen, which is why putting on the oxygen masks is critical. Additionally, securing seat belts helps to keep passengers safe and prevents them from potentially being injured or moving around in a chaotic situation. The instruction to "pull mask firmly" reinforces the importance of ensuring that the mask fits securely over the nose and mouth to provide adequate oxygen supply.

These steps are crucial for maintaining safety and ensuring that everyone can breathe properly until the situation stabilizes or the aircraft descends to a safe altitude.