List of United States Navy ratings
Engineering and hull ratings

List of United States Navy ratings

Section Title: Engineering and hull ratings
Table Section Text: None

Insignia	General rating	Abbreviation	Service rating	Abbreviation

-	Damage controlman	DC

Damage controlmen perform the work necessary for damage control, ship stability, fire-fighting. They also prepare defenses against chemical, biological and radiological (CBR) warfare attacks.

-	Electrician's mate	EM	(Nuclear)	EMN

Electrician's mates are responsible for the operation and repair of a ship's or station's electrical power plant and electrical equipment. They also maintain and repair power and lighting circuits, distribution switchboards, generators, motors and other electrical equipment.

-	Engineman	EN

Enginemen are responsible for internal diesel and gasoline engines. They also maintain refrigeration, air-conditioning, distilling-plant engines and compressors.

-	Gas turbine system technician	GS	(Electrical) (Mechanical)	GSE GSM

Gas turbine system technicians are responsible for all gas turbine engines. They maintain propulsion machinery, including gears, shafting and controllable pitch propellers, assigned auxiliary equipment propulsion control systems, electrical and electronic circuitry up to the printed circuit module, and alarm and warning circuitry.

-	Hull maintenance technician	HT

Hull maintenance technicians are responsible for maintaining ships' hulls, fittings, piping systems and machinery. They install and maintain all shipboard and shore based plumbing and piping systems.

-	Interior communications electrician	IC

Interior communications electricians operate and repair electronic devices used in the ship's interior communications systems, SITE TV systems, 1MC (public address system), electronic megaphones and other announcing equipment.

-	Machinist's mate	MM	(Nuclear) submarine (Weapons) submarine (Auxiliary)	MMN MMW MMA

Machinist's mates are responsible for the continuous operation of the many engines, compressors, gears, refrigeration, and air-conditioning equipment along with other types of machinery onboard ships and shore installations.

-	Machinery repairman	MR

Machinery repairmen are skilled machine tool operators. They make replacement parts and repair or overhaul a ship's engine auxiliary equipment, such as evaporators, air compressors and pumps.

-	Navy diver	ND

Navy divers are responsible for a wide variety of tasks like underwater ship maintenance, construction, and underwater rescue. They are assigned to Naval Special Warfare Units to provide diving technical expertise and supervisory support to all submersible operations.

Sentence(s)

Machinist's mate (or MM) is a rating in the United States Navy community.

final_sentence: Machinist's mate (or MM) is a rating in the United States Navy community.