One or more actions necessary to prevent or interrupt complete function of the system (traditionally synonymous with “dearm,” “disarm,” and “disable”). Among the necessary actions are: (1) install (safety devices such as pins or locks); (2) disconnect (hoses, linkages, batteries); (3) bleed (accumulators, reservoirs); (4) remove (explosive devices such as initiators, fuzes, detonators); and (5) intervene (as in welding, lockwiring).