<P> Unlicensed personnel (synonymous with ratings) are generally trained through several private programs funded by maritime unions, shipping companies, or by one's own expense . An example training institution would be the Paul Hall Center for Maritime Training and Education, or better known as "Piney Point ." Generally the merchant mariner works their way up through the rates with sea time on the job . Entry level ratings would be ordinary seaman in the deck department and marine wiper in the engineering department . </P> <P> Unlicensed personnel must have sufficient sea time in a qualified rating and complete specified testing and training . These requirements are outlined in the International Convention on Standards of Training, Certification, and Watchkeeping for Seafarers (STCW), to advance in rate . </P> <P> Limited tonnage licensed mariners hold senior positions aboard small ships, boats, and similar vessels, but are restricted to certain tonnages (under 1600 GRT), types of vessels, and geographic locations . </P> <P> Several laws shaped the development of the U.S. Merchant Marine . Chief among them are the "Seamen's Act of 1915," the "Merchant Marine Act of 1920" (commonly referred to as the "Jones Act"), and the "Merchant Marine Act of 1936 ." </P>

Basic cargo ship used by the u.s. during world war ii