There are many different strands to education and training.

South Tyneside Marine College

http://www.stc.ac.uk/content/marine-college/marine-school

The International Boat building and Training College

http://www.ibtc.co.uk/

The Lyme Regis Boat building Academy

http://www.boatbuildingacademy.com/index.htm

The Royal Yachting Association (RYA) coordinates much of the regulation around the pleasure boating

http://www.rya.org.uk/Pages/Home.aspx

http://www.rya.org.uk/AboutRYA/Pages/aboutrya.aspx

While the Maritime and Coastguard Agency (MCA) regulate the operation of "Shipping".

http://www.mcga.gov.uk/c4mca/mcga07-home

There are lists of critera defining where a boat becomes a ship, generally speaking, for a sea going motoriesd vessel it will be classed as a ship if it has a waterline length greater than 24 meters or a Displacement of over 500T. Although, there are many different regulations, for all the different purposes of vessel, ensuring safey on the high seas, through setting and Monitoring standards, in both vessel maintenance and crew competence.