Adoption: 29 November 1969
Entry into force: 6 May 1975

The Convention affirms the right of a coastal State to take such measures on the high seas as may be necessary to prevent, mitigate or eliminate danger to its coastline or related interests from pollution by oil or the threat thereof, following upon a maritime casualty. The 1973 Protocol extended the Convention to cover substances other than oil.

Introduction
The Protocol of 1973 - extension to other substances
The 1991 amendments - revision of list of substances
The 1996 amendments - revision of list of substances
The 2002 amendments - revision of list of substances

Introduction
The Torrey Canyon disaster of 1967 revealed certain doubts with regard to the powers of States, under public international law, in respect of incidents on the high seas. In particular, questions were raised as to the extent to which a coastal State could take measures to protect its territory from pollution where a casualty threatened that State with oil pollution, especially if the measures necessary were likely to affect the interests of foreign shipowners, cargo owners and even flag States.

The general consensus was that there was need for a new regime which, while recognizing the need for some State intervention on the high seas in cases of grave emergency, clearly restricted that right to protect other legitimate interests. A conference to consider such a regime was held in Brussels in 1969.

The Convention which resulted affirms the right of a coastal State to take such measures on the high seas as may be necessary to prevent, mitigate or eliminate danger to its coastline or related interests from pollution by oil or the threat thereof, following upon a maritime casualty.

The coastal State is, however, empowered to take only such action as is necessary, and after due consultations with appropriate interests including, in particular, the flag State or States of the ship or ships involved, the owners of the ships or cargoes in question and, where circumstances permit, independent experts appointed for this purpose.

A coastal State which takes measures beyond those permitted under the Convention is liable to pay compensation for any damage caused by such measures. Provision is made for the settlement of disputes arising in connection with the application of the Convention.

The Convention applies to all seagoing vessels except warships or other vessels owned or operated by a State and used on Government non?commercial service

The Protocol of 1973
Adoption: 2 November 1973
Entry into force: 30 March 1983

The 1969 Intervention Convention applied to casualties involving pollution by oil. In view of the increasing quantity of other substances, mainly chemical, carried by ships, some of which would, if released, cause serious hazard to the marine environment, the 1969 Brussels Conference recognized the need to extend the Convention to cover substances other than oil.

Following considerable work on this subject within IMO's Legal Committee, draft articles for an instrument to extend the application of the 1969 Convention to substances other than oil were prepared and submitted to the 1973 London Conference on Marine Pollution.

The Conference adopted the Protocol relating to Intervention on the High Seas in Cases of Marine Pollution by Substances other than Oil. This extended the regime of the 1969 Intervention Convention to substances which are either listed in the Annex to the Protocol or which have characteristics substantially similar to those substances.

The 1991 amendments
Adoption: 4 July 1991
Entry into force: 30 March 1993

The amendments revised the list of substances drawn up in 1974 to assist the application of the 1973 Protocol.

The 1996 amendments
Adoption: 10 July 1996
Entry into force: 19 December 1997

The amendments revised the list of substances attached to the 1973 Protocol, following the adoption of new criteria for their selection.

The 2002 amendments
Adoption: 11 October 2002
Entry into force: 22 June 2004

The amendments revised the list of substances attached to the 1973 Protocol