Low pressure air must be ______ prior to the main cabin door being closed and secured.

• A. On
• B. Off
• C. Standby
• D. Auto

Answer: (B)

Pneumatic action around the door must be neutralized before closing. If the low pressure air is still on, it can push or pull on the door or its seals as you try to close and latch it, making alignment difficult and potentially causing damage or injury. Turning the air off removes any pressure-driven movement, allowing the door to close smoothly, the latch to engage properly, and the seal to seat evenly. This safety step helps ensure the door is secured reliably without interference from the pneumatic system.