A system of locking a door is disclosed. The system according to the
present invention comprises a releasable keeper that secures a door
locking mechanism to keep a door secured to an enclosure in a locked
position. A release mechanism that is operated from the interior of the
enclosure releases the releasable keeper from the enclosure and enable
the door to be opened and prevents people from becoming trapped within
the enclosure by a locked door. In an exemplary embodiment, the release
mechanism is operated by a lever that operates a pulley system to
disengage the release mechanism from the releasable keeper.