Annex IV
A3. Marine environmental legislation: MARPOL and its annexesDefinition
Regulations for the Prevention of Pollution by Sewage from Ships.
MARPOL Annex IV regulates discharge of sewage from ships, applying to ships of 400 GT and above and to those certified to carry more than 15 persons on international voyages. It prohibits sewage discharge except at set distances from the nearest land, faster than 4 knots, with comminuted and disinfected sewage closer in, or through an approved treatment plant. It requires the ISPP Certificate and entered into force on 27 September 2003.
Source: MARPOL Annex IV, in force 27 September 2003