Six annexes against pollution from ships, and the protocol that rescued a stalled treaty

Background

The International Convention for the Prevention of Pollution from Ships, known as MARPOL, is the main international convention covering prevention of pollution of the marine environment by ships from operational or accidental causes. It was adopted on 2 November 1973 at IMO, but had not yet entered into force when the Protocol of 1978, adopted in response to a spate of tanker accidents in 1976-1977, absorbed the parent Convention; the combined instrument entered into force on 2 October 1983. MARPOL currently includes six technical Annexes, and Special Areas with strict controls on operational discharges are included in most Annexes. Annex I on oil and Annex II on noxious liquid substances in bulk both entered into force on 2 October 1983, and the 1992 amendments to Annex I made double hulls mandatory for new oil tankers. Annex V on garbage, in force from 31 December 1988, imposes a complete ban on the disposal into the sea of all forms of plastics. Annex VI on air pollution was added by a Protocol adopted in 1997 and entered into force on 19 May 2005; it sets limits on sulphur oxide and nitrogen oxide emissions from ship exhausts and prohibits deliberate emissions of ozone depleting substances.