There is an international convention (big surprise!):
International Convention for the Prevention of Pollution from Ships, 1973, as modified by the Protocol of 1978 relating thereto (MARPOL 73/78).I give you a link here but I doubt any of you would have the time and interest to study the subject further in detail (but who knows?):
Most of this convention deals with rules for dangerous goods like chemicals carried in bulk, oil tankers and the like. But in fact some of MARPOL already applies to yachts. This is what most registries demand:
MARPOL/IOPPC: Compliance with the International Convention for the Prevention of Pollution from Ships, 1973, as amended by the Protocol of 1978 (MARPOL), is required as follows:
Annex I (Pollution by Oil) is applied to all yachts regardless of size unless expressly provided otherwise. All yachts are required to maintain an oil record book.
All yachts of 400 gross tons or more are required to be issued and carry on board an International Oil Pollution Prevention Certificate (IOPPC) in accordance with Regulation 5 of Annex I.
Annex IV (Pollution by sewage) is applied to all yachts certified to carry more than 15 persons on board and to all yachts of 400 gross tons or more regardless of the number of persons on board in accordance with Regulation 2.
A sewage system has to be in place and an international sewage pollution prevention certificate to be issued (no later than Sept 2008 but some flag states already apply this regulation).
Most newer yachts already comply with the sewage treatment regulations.
Thank you Hamann, Marinfloc & Co!
Annex V (Pollution by garbage) is applied to all yachts regardless of size unless expressly provided otherwise.
Annex VI (Air Pollution) applies already to diesel engines (machinery exhaust emissions). In the future we will see demands for catalytic exhaust purification generalized.
The important thing to remember is that all yachts (private & commercial!) must have the IOPP certificate if they measure 400GT or more. Basically the question is about the prevention of pollution by oil coming from dirty bilges and ballast tanks, waste oil from machineries etc. The equipment installed (filters, separators, sludge tanks etc) are to be certified. For those wanting to study this interesting domain in detail here is the link :
Modified by Andy Lindy at 5:36 PM 8/5/2004