Related Military Skill. The related DOT classification/ DOT code lists the comparable civilian classification title(s) and code(s) that are presented in the U.S. Department of Labor Dictionary of Occupational Titles (DOT).
OCCUPATIONAL SYSTEM. The Marine Corps Occupational System has been constructed on the concept that similar skill and knowledge requirements are grouped in functional areas, known as OccFlds, which provide for the most efficient and effective classification, assignment, promotion, and utilization of Marine Corps personnel.
MOS SYSTEM. The MOS system is composed of OccFlds and MOSs within each OccFld.
OccFld. The OccFld is identified by the first two digits of a four-digit number and a descriptive title. The OccFld is a grouping of related MOSs. Criteria to be considered in establishment of an OccFld include the total number of Marines in the field, the number of MOSs (diversity), combat or combat support requirements, rotation base, training requirements, promotion opportunity, and the self-renewing characteristics of the field.
MOS. An MOS code has four digits and a descriptive title. The MOS describes a group of related duties and tasks that extend over one or more grades. Duties and tasks are identified by grade since the Marine Corps MOS system is predicated on the fact that increased duties and tasks accompany promotion to higher grade. The first two digits designate the OccFld and the last two digits identify the promotional channel and specialty within the OccFld.
Criteria to be considered in establishment of an MOS include the number of Marines required in the specialty, combat or combat support relationship, rotation base, training requirements, specialty requirements/prerequisites, promotion opportunity, and career pattern.
Skill Designator. A nonprimary MOS. May be found in Category "B" MOSs or in regular Occflds. Skill designator MOSs within OccFlds are usually low density MOSs that require foundation skills acquired in a related primary MOS. Example from OccFld 35: Primary MOS 3521 with skill designators 3522, 3523, 2524, 3525. Throughout the Manual, skill designator MOSs are indicated by an asterisk.
BASIC MOS'S. Each OccFld contains a basic MOS; e.g., MOS 0100 (basic administrative Marine). A basic MOS represents the entry-level learner in an OccFld. It is assigned as a specific MOS in that field or upon being assigned for retraining, a Marine's primary MOS (gunnery sergeant through private grades), will be changed to the basic MOS in the OccFld while in a retraining status.
Category B. MOSs 8000-9599 (except 8412). Enlisted only billet MOSs, non-PMOS, appearing on T/Os where special skills or an accounting for structure is required. The overall population is not managed as a community. Marines are promoted by PMOS even while serving in Category "B" billets.
* - indicates a skill designator MOS.
# - indicates a note at the end of the MOS.
Aptitude area (AA) score
The subtests for determining the composites are: General Science (GS), Arithmetic Reasoning (AR), Word Knowledge (WK), Paragraph Comprehension (PC), Numerical Operations (NO), Coding Speed (CS), Auto and Shop Information (AS), Mathematics Knowledge (MK), Mechanical Comprehension (MC), Electronics Information (EI), and Sum of Word Knowledge and Paragraph Comprehension (VE). Current aptitude area composites used for MOS selection are as follows:
CL-Clerical-VE+AR+MK (Note: CL Score was eliminated in late 2002. All job Marine Corps requirements that required a CL score were changed to GT Score at this time. The score requirements are the same. In other words, if a job previously required a CL score of 90, then it was changed to require a GT score of 90).
CO-Combat-AR+CS+AS+MC
EL-Electronics-GS+AR+MK+EI
FA-Field Artillery-AR+CS+MK+MC
GM-General Maintenance-GS+AS+MK+EI
GT-General Technical-VE+AR
MM-Mechanical Maintenance-NO+AS+MC+EI
OF-Operators and Food-VE+NO+AS+MC
SC-Surveillance and Communications-VE+AR+AS+MC
ST-Skilled Technical-GS+VE+MK+MC
