What must be confirmed before making the arm door announcement?

Before making the arm door announcement, it is essential to confirm that the door is closed. This step is critical as it ensures the safety and security of all individuals on board the aircraft. The arm door announcement signifies that the doors are prepared for departure or landing, and if the door is not closed, it could lead to serious safety hazards, such as unintentional door openings during flight. Confirming the closure of the door helps to ensure that all safety protocols are being followed and that the aircraft is ready for its next phase of operation.

While it is also important for passengers to be seated and for the flight crew to be ready, these elements do not take precedence over the security of the aircraft, which is why confirming the closure of the door is the primary focus before making the announcement.