What is the blocking procedure for an inoperative lavatory?

• A. Lavatory door is locked; Lavatory is clearly marked as inoperative
• B. Lavatory remains accessible to crew only
• C. Lavatory is removed from service and replaced post-flight
• D. Lavatory door is left unlocked for emergency use

Answer: (A)

When a lavatory is out of service, the blocking procedure is to make it clearly unavailable to passengers by locking the door and placing a visible “Inoperative” mark. This immediately communicates to everyone that the lavatory cannot be used, preventing confusion and safety issues. The door being locked stops accidental entry, and the sign provides a clear, lasting indicator for crew and passengers alike. In this scenario, maintenance actions like removing the unit from service and replacing it after the flight are handled by ground staff and aren’t the in-flight blocking step. Leaving the door unlocked or restricting access only to crew would undermine safety and the clear communication needed when a lavatory is not usable. If other lavatories are available, crew will redirect passengers accordingly and inform the cabin.