Safety apparatus is disclosed for providing ballistic train interruption
in a perforating system. The safety apparatus comprises a generally
tubular shaped housing having first and second ends which are fabricated
to permit the housing to be positioned at any location in the perforating
system. The apparatus comprises first and second ballistic sections in
the housing and a third ballistic section which is rotatably mounted in
the housing to move between a disarmed position and an armed position
based on downhole pressure. Upon retrieval of the perforating system from
the wellbore, the safety apparatus functions to return a third ballistic
section to its disarmed position. Additionally, apparatus is provided to
permanently disable the third ballistic section to insure that no
inadvertent detonation of the guns occurs when retrieving the system from
a wellbore.