Domanda 307, Operational Procedures - ATPL - Airline Transport Pilot license

A device preventing the flight crew from being locked in the cockpit.
A locking system to prevent any unauthorized access.
A sealing system which, in case of depressurisation in the compartment area allows the maintenance of the pressure in the cockpit for as long as possible.
Distinctive red or yellow coloured markings indicating the access area (in case of a blocked door).