via  the  chain  of  command.  When  making recommendations for NEC WP-9999, make sure you fully justify the use of this NEC. Be prepared, on request, to provide continued justification for such billet codings. ENLISTED PRIORITY MANNING Because the mission of some activities is vital to our national interest, these activities must be properly manned, even when overall personnel shortages exist. Thus, they receive priority manning. Authorized priority manning is indicated on an activity’s MPA. It may include up to 1000-percent manning in quality and quantity or both for all or part of the activity. Priority manning may be on a continuous basis or for a specified period. Because the priority manning of one activity means the undermanning of other activities, continuous efficient management of authorized manning is required. Three priority manning categories, priorities 1,2, and 3, are used: Priority 1. Ships and activities requiring priority manning for an indefinite period to carry out a mission of vital interest to our nation are authorized priority 1 manning. Priority 1 manning is limited to that portion of the activity essential to mission success. Only the CNO may authorize and direct priority 1 manning. Priority 2. Ships and activities requiring increased manning for a specific period to carry out a mission that is essential to our national interest are authorized priority 2 manning. Priority 2 manning is limited to that portion of the activity essential to mission success. Only the CNO may authorize and direct priority 2 manning. Priority 3. Ships and activities having a specific need  for  increased  manning  for  specific  mission accomplishment are authorized priority 3 manning by the respective manning control authority. Priority 3 manning is normally authorized for a maximum period of 1 year. Priority 3 manning authorizations are automatically cancelled on 31 March of each year, unless a specific date is otherwise authorized. The priority manning system is generally limited to manning whole activities, whole ratings within the activity, or the whole specific NEC community in an activity. Remember that when you request priority manning because requests for specific priority manning beyond-the general limitations special  processing.  Requests of the system receive for priority manning should be made only when such manning is mandatory for mission accomplishment. CHANGES TO MANPOWER AUTHORIZATION Each Navy activity reviews its manpower requirements and classifications each year This review ensures the deletion of unnecessary billets or positions and the proper classification of each authorized billet or position. If changes are required, submit a Manpower Authorization Change Request, OPNAV1000/4A (fig. 6-2). If you request changes to ratings, rates, or the number of billets/positions, you need to justify the requests. Your justification should explain the changes in mission, function, and tasks or why the billet is classified wrong. Make every effort to include all necessary requests for changes in your MPA during the annual review. Justify the submission of MPA change requests other than once annually. Base your justifications on changes in mission or functions beyond the control of your activity. Request billet classifications on the basis of the duties, tasks, and functions to be performed. You should not request changes in the classification of billets to accommodate an incumbent or to require the services of a particular person. New billets are not normally established for a time duration less than a normal tour of duty. You can find procedures for requesting MPA changes in the Manual of Navy Total Force Manpower Policies and Procedures, OPNAVINST 1000. 16G. CIVILIAN MANPOWER Civilian positions within the Department of the Navy are separated into several groups or pay categories, including the following principal categories: Senior Executive Service. Includes executives and high-level managerial positions. General Schedule (GS). Includes workers in administrative, clerical, scientific, artistic, or technical fields, including positions in the merit pay system (General Management [GM] employees). Wage Grade (WG). Includes positions in trades, crafts, or manual labor occupations. 6-5