Military Occupational Specialty

A United States military occupation code, or a military occupational specialty code (MOS code), is a nine character code used in the United States Army and United States Marines to identify a specific job. In the United States Air Force, a system of Air Force Specialty Codes (AFSC) is used. In the United States Navy, a system of naval ratings and designators was used along with the Navy Enlisted Classification (NEC) system: however, on September 29, 2016 the United States Navy discontinued enlisted ratings after two hundred and forty one years of use. Naval service members thereafter were to be referred to solely by their rank and would hold a Navy Operations Specialty (NOS) instead of a rate.

Since an individual can obtain multiple job specialties, a duty military occupational specialty (DMOS) is used to identify what their primary job function is at any given time. An individual must complete and pass all required training for their military occupational specialty qualification (MOSQ).

Originally, the MOS system had three to five digits. The first four-digit code number indicated the soldier's job; the first two digits were the field code, the third digit was the sub-specialty and the fourth code number (separated by a period) was the job title. A fifth code digit was for the soldier's special qualification identifier (SQI), which indicated what specialized training the soldier had. If the soldier did not have an SQI, the digit was listed as "0" or was omitted.

One-one is the field code for infantry, 1.1 is the sub-specialty of light weapons, and seven is the SQI for airborne training. Therefore, 111.10 is the MOS for an infantryman and 111.17 is for an airborne-qualified paratrooper. Nine-one was the old field code for the medical field, 912.0 is the MOS for medical NCO and 912.00 is a generalist medical NCO with no SQI.

In 1965 the system was revamped. There were completely different codes for enlisted / non-commissioned officers, warrant officers, and commissioned officers.

Enlisted and NCO personnel had a five-symbol code. The first four code symbols were made up of a two-digit code for the career field, a letter code for the field specialty, and a number code (1 to 5) indicating level of instruction in their field specialty. The fifth code symbol was an SQI code letter indicating training in a special skill (the letter "O" indicating that the soldier had no SQI).

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