 Under international conventions and agreements specifically the International Convention on Standards of Training, Certification and Watchkeeping for Seafarers (or STCW), all oilers who sail internationally are documented by their respective countries.Recent changes to the STCW no longer refer to specific rates such as oiler.The terms Able Seafarer-Engine and Able Seafarer-Deck are now used to refer to unlicensed positions on vessels engaged in international trade.