The door lock control mechanism in a nuclear waste storage facility is designed for safe operation. It ensures that entry to the storeroom is only permitted when radiation shields are in place or when the radiation level in the room falls below some given value (dangerLevel).

That is:

(i) If remotely controlled radiation shields are in place within a room, the door may be opened by an authorised operator.

(ii) If the radiation level in a room is below a specified value, the door may be opened by an authorised operator.
(iii) An authorised operator is identified by the input of an authorised door entry code.
The Java code shown in Figure