Maritime Rules, Regulations and Codes


Maritime Rules, Regulations and Codes

International Convention for the Prevention of Pollution from Ships (MARPOL)


The world’s oceans provide us with 50% of our oxygen and abundant natural life, pleasure, food, exploration and a means of travel and commerce. Until the middle of the 20th century, it was believed that the oceans were so vast, they had an unlimited ability to dilute and render any pollution harmless, so rivers and oceans became a dumping ground for anything from sewage to chemical plant run-off.

Simultaneously, there was a growing understanding of the human impact and damaging effects that bad practices in shipping were having on the marine environment. In 1948, the United Nations established the International Maritime Organization (IMO) to ensure “Safe, Secure and Efficient Shipping on Clean Oceans”.  From 1954, they became custodians of OILPOL 54, tackling oil pollution from routine operations such as cargo tank cleaning. 

However, an increase in tanker size and number of voyages saw many tragic accidents in the 1950’s and 1960’s. As a result, crude oil and pollutants were released into the oceans in unprecedented amounts.

In March 1967, navigational problems led to the supertanker Torrey Canyon running aground on the Seven Stones Reef off the Isles of Scilly. Salvage attempts failed and the ship broke in two, spilling her entire cargo of 119,000 tonnes of crude oil. The Royal Navy attempted to mitigate the damage by bombing the ship and igniting the oil with napalm. They failed and the slick spread over 270 square miles, killing millions of sea organisms and some 200,000 birds - polluting the delicate coastline.

The scale of this disaster galvanised the international community to demand change, leading to the International Convention for the Prevention of Pollution from Ships (MARPOL), adopted in November 1973 at the IMO. These regulations covered the prevention of pollution in the marine environment caused by ships through operational or accidental causes. 

There are currently 6 Annexes to MARPOL in force.

Annex I provides regulation for prevention of pollution by oil. Originally, this included requirements for new oil tankers to be fitted with segregated ballast tanks. The devastating effect of the Exxon Valdez oil spill in Alaska meant that since 1996, new tankers are built with a double hull, creating a buffer around the oil in case of a casualty. Ships also now have tanks to store waste oil and efficient water separators to clean contaminated water from oil before it is discharged into the sea.

Annex II regulates the control of pollution by Noxious Liquid Substance in bulk. It details how 250 listed chemicals should be kept, stored, and discharged at reception facilities ashore, instead of the sea.

Annex III provides regulation to prevent pollution by harmful substances carried at sea in packaged form. It requires all harmful substances to be clearly labelled and survivability of containers lost overboard of up to 3 months.

Annex IV controls pollution by sewage from ships. It was introduced in September 2003 and deals with the proper treatment and disposal of sewage. Imagine the amount of sewage from a modern cruise ship which can have as many as 9000 passengers and crew - that’s a lot of toilets!

Annex V regulates pollution by garbage and details how to safely dispose of all rubbish, except fish waste, as it comes from the sea and can be returned to the sea’s environment!  As we are beginning to understand, micro plastics are a real problem, and it can take up to 450 years for a plastic bottle to decompose.

Annex VI limits the main air pollutants in shipping, especially exhaust gases. All ships should use cleaner fuels and new ships must be built with more efficient burning engines. Research by CE Delft suggests an inefficient vessel creates pollutants equivalent to 50 million private cars - the same as on German roads today.

By 2022, MARPOL had been ratified by 150 countries, representing over 98 percent of merchant shipping worldwide. This is a great achievement, however, there is a need for constant vigilance.  More checks need to be made, the MARPOL conventions should continue to be updated, and new technology should be used to lessen the impact of shipping on the environment and the world’s oceans.