The Third Assistant Engineer, also known as the Fourth Engineer, is a licensed member

Licensed mariner

A licensed mariner is a person who holds a license issued by one or more countries to hold senior positions aboard ships, boats, and similar vessels. The United States Coast Guard grants licenses to members of the United States Merchant Marine in five categories: deck officers, engineers, staff...

 of the engineering department on a merchant vessel

Merchant vessel

A merchant vessel is a ship that transports cargo or passengers. The closely related term commercial vessel is defined by the United States Coast Guard as any vessel engaged in commercial trade or that carries passengers for hire...

.

Generally the most junior marine engineer of the ship, this person is usually responsible for electrical, sewage

Sewage

Sewage is water-carried waste, in solution or suspension, that is intended to be removed from a community. Also known as wastewater, it is more than 99% water and is characterized by volume or rate of flow, physical condition, chemical constituents and the bacteriological organisms that it contains...

 treatment, lube oil, bilge

Bilge

The bilge is the lowest compartment on a ship where the two sides meet at the keel. The word was coined in 1513.-Bilge water:The word is sometimes also used to describe the water that collects in this compartment. Water that does not drain off the side of the deck drains down through the ship into...

, and oily water separation systems. Depending on usage, he or she is called "The Third" or "The Fourth" and usually stands a watch and sometimes assists the third mate

Third Mate

A Third Mate or Third Officer is a licensed member of the deck department of a merchant ship. The third mate is a watchstander and customarily the ship's safety officer and fourth-in-command...

 in maintaining proper operation of the lifeboats

Lifeboat (shipboard)

A lifeboat is a small, rigid or inflatable watercraft carried for emergency evacuation in the event of a disaster aboard ship. In the military, a lifeboat may be referred to as a whaleboat, dinghy, or gig. The ship's tenders of cruise ships often double as lifeboats. Recreational sailors sometimes...

.

Maritime academies such as the U.S. Merchant Marine Academy offer a four year program leading to a BS in Marine Engineering Technology, a license (issued by the Coast Guard) as a third assistant engineer, and an optional commission as ensign in the U.S. Naval Reserve, Merchant Marine Reserve, or Coast Guard Reserve. With experience and additional training, third officers may qualify for higher rank.

See also

• Seafarer's professions and ranks
  Seafarer's professions and ranks
  Seafarers hold a variety of professions and ranks, and each of these roles carries unique responsibilities which are integral to the successful operation of a seafaring vessel...
  
  
• Engine room
  Engine room
  On a ship, the engine room, or ER, commonly refers to the machinery spaces of a vessel. To increase the safety and damage survivability of a vessel, the machinery necessary for operations may be segregated into various spaces, the engine room is one of these spaces, and is generally the largest...
  
  
• Engineering department

External links

• Description at WomenOceanographers.org
• Job Description at WHOI
• Job Description at Human Resources and Skills Development Canada
• Job Description at Maritime Industry Authority Philippines