Army Regulation (AR) 611-1, titled "Military Occupational Classification Structure Development and Implementation," covers the requirements for Military Occupational Specialty (MOS). This regulation outlines the processes for establishing and managing MOS designations and criteria related to personnel qualification and training. It serves as a guide for determining the qualifications and skills needed for specific roles within the Army.
There are multiple regulations which blanket every MOS. There are multiple regulations pertaining both to all skill levels and to Skill Level 4 personnel. You're not going to find the entire scope of regulations in one paragraph.
The essence of government is not to obey, but to enforce obedience. And therefore it always strives for that and will never willingly abandon its power. But since the power of government rests on the army, it will never give up the army, and the use of the army. Tolstoy The Kingdom of God is Within You
The safest MOS in the Army would be one dealing with the Army Band, Human Resources, or finance. These include the MOS - 42F, 42R9B, 42 S, or 44C.
MOS Military Occupational Specialty
Short answer: Their Regimental Affiliation. Long Answer is spelled out in Army Regulation 600-82. http://www.apd.army.mil/pdffiles/r600_82.pdf
Army 82nd airbone is a MOS. This is a job in the Army.
11B2V is the MOS for an Infantry, E5 Sergeant, Ranger .
Mail clerk is a supplemental duty - it doesn't carry its own MOS.
91W
MOS, military occupational specialty
Anywhere, 35F Intelligence Analyst is a MOS that can be stationed at any Army Base.
Yes the can, some non medic soldiers also get training on starting iv's by going through the combat life savers course. Since the reorganisation of Army MOS structure circa 2001 - 2002, the MOS of Combat Medic has been greatly expanded, and also covers a lot of personnel who previously wouldn't have been classed as combat medics under the old structure (91B was the MOS for a Combat Medic previously - now it's 68W). With the reorganisation, new requirements were put in place for Combat Medics, one of which was that a Combat Medic should hold a basic EMT licence (national registry).