Planned Maintenance (PM). Work accomplished in response to periodically scheduled preventative maintenance normally mandated by the Planned Maintenance System (PMS). In quantative terms, it is the total workload associated with the performance of preventive maintenance actions on operational systems, equipment, or componenets contributing to uninterrupted operations within design characteristics.
Corrective Maintenance (CM). Work accomplished on an unscheduled basis because of malfunction, failure, or deterioration. In quantitative terms, it is the workload associated with restoration of disabled systems, equipment, or components to an operational condition within predetermined tolerance and limitations for which there is a corresponding PM action. CM performed on equipment material not supported by the Maintenance and Material Management (3-M) System is covered under OUS.
Facilities Maintenance (FM). The quantitative and qualitative sum of the manpower needed to maintain the material condition of the ship. FM is work accomplished to maintain cleanliness and sanitation of all habitable areas and to preserve the hull, decks, superstructure, and equipment against corrosion and deterioration.