The world’s
oceans cover 70% of the Earth’s surface and are essential to life on our planet, supporting everything from
global trade to biodiversity.
As the
UN agency dedicated to shipping safety and pollution prevention,
IMOplays a leading role in protecting these vital resources. Through key conventions, climate and ocean actions and global partnerships, IMO is committed to ensuring the oceans remain healthy and sustainable for generations to come.
Learn all about how IMO is protecting the oceans below.
Key events in 2025
"Our Ocean, Our Obligation, Our Opportunity"World Maritime Day theme 2025. IMO's World Maritime Day theme for 2025 is "Our Ocean, Our Obligation, Our Opportunity". The
celebration runs through the year, and it will culminate in official observance of World Maritime Day on 25 September 2025. Read more here.
2025 UN Ocean Conference (9-13 June 2025, Nice, France). IMO will be present at the UN Ocean Conference, dedicated to advancing urgent action for the conservation and sustainable use of oceans, seas, and marine resources. More information coming up soon.
Protecting the ocean through regulation
For decades, IMO has developed and adopted mandatory regulations, along with recommendations and guidelines, to
protect the marine environment from the potential impacts of shipping activities.
Explore the key IMO Conventions for ocean protection below:
The MARPOL Convention is one of the key conventions to protect the oceans, by preventing and minimizing pollution from shipping. Initially adopted in 1973, MARPOL includes annexes addressing the prevention of pollution from ships by oil, chemicals carried in bulk, packaged goods, sewage, and garbage. In 1997, the convention was expanded to include regulations on air pollution and emissions from ships.
Read more here.
The SOLAS Convention is one of the most important treaties for maritime safety. It establishes minimum safety standards for ships, including lifesaving equipment, fire protection, navigation, and operational safety.
Read more here.
The OPRC Convention establishes measures for the prevention of, preparedness for, and response to oil pollution incidents. It requires countries to develop contingency plans and establish cooperation between states and international organizations for oil spill response. The OPRC-HNS Protocol (2000) extends this framework to cover hazardous and noxious substances (HNS) in addition to oil.
Read more here.
The AFS Convention regulates the use of harmful anti-fouling systems (substances used to prevent marine organisms from attaching to ships’ hulls) to protect the marine environment from chemicals that can be harmful to marine life.
Read more here.
The Ballast Water Management Convention aims to prevent the spread of harmful aquatic organisms and pathogens through ballast water discharge. It requires ships to manage ballast water through treatment systems, ballast water exchange, and the safe disposal of ballast water and sediment to prevent the introduction of invasive species into new marine environments.
Read more here.
The Hong Kong Convention is aimed at ensuring that ships, when being recycled after reaching the end of their operational lives, do not pose any unnecessary risk to human health and safety or to the environment.
Read more here.
The STCW Convention sets qualifications for the training, certification, and watchkeeping of seafarers, ensuring they meet specific safety standards at sea, which is essential for preventing accidents, spills, and other incidents and protecting the ocean environment.
Read more here.
The London Convention and Protocol regulate the dumping of waste and harmful materials into the ocean to protect the marine environment. In addition to addressing pollution from ships, the Protocol adopts a precautionary approach to land-based waste and supports climate change mitigation through carbon capture and subsea sequestration.
Read more here.
Ocean areas of action
IMO is addressing
critical issues affecting our oceans . As part of IMO's efforts to protect the
marine environment and ensure sustainable shipping practices, IMO has implemented several essential conventions through
key areas of action.
Marine Litter
Marine plastic pollution is one of the most critical environmental concerns of our time. IMO addresses marine litter in its commitment to reducing pollution in the oceans. Through
MARPOL Annex V, the Organization aims to
prevent pollution by banning the discharge of most types of garbage from ships, including plastics, and setting standards for waste management.
IMO adopted the 2025 Action Plan to Address Marine Plastic Litter from Ships (2025 Action Plan) at MEPC 83 in April 2025. This updated plan aim to achieve at the following main outcomes:
Reduction of the contribution from fishing vessels to marine plastic litter
Reduction of shipping’s contribution to marine plastic litter
Enhanced public awareness, education and seafarer training
Improvement of the effectiveness of port reception facilities and treatment in reducing marine plastic litter
Improved understanding of the contribution of ships to marine plastic litter
Regarding the transport of plastic pellets in freight containers, the MEPC 83 noted a dedicated action in the 2025 Action Plan to develop mandatory measures aimed at minimizing the environmental risks posed by these pellets when transported by sea. More information about plastic pellets here.
IMO is committed to
protecting and rebuilding biodiversity upon which the world relies.
By implementing
IMO's global regulatory framework on marine environment protection IMO is supporting global efforts to address some of the challenges the planet faces through strengthened international cooperation.
The introduction of
invasive aquatic species to new environments by ships, mainly through ballast water or hull fouling, poses a
significant threat to marine biodiversity.
This work supports the implementation of global biodiversity commitments, including the Kunming-Montreal Global Biodiversity Framework adopted at COP 15 in 2022, which sets ambitious goals for protecting and restoring ecosystems by 2050.
To address this issue, the
Ballast Water Management Convention (2004) requires ships to implement practices and treatment systems to
prevent the transfer of invasive species from one ecosystem to another.
Biofouling, the undesirable accumulation of microorganisms, plants, algae and animals on submerged structures (especially ships' hulls), is a major pathway for the spread of invasive aquatic species. It poses serious risks to marine biodiversity and ecosystem balance.
In April 2025, IMO's Marine Environment Protection Committee (MEPC 83) has agreed to on a new output to develop a legally binding framework for the control and management of shipsʹ biofouling to minimize the transfer of invasive aquatic species.
Until the new framework is adopted, the 2023 Guidelines for the control and management of ships' biofouling to minimize the transfer of invasive aquatic species (Biofouling Guidelines) continue to provide a globally consistent approach to managing biofouling on ships.
A significant portion of the underwater noise generated by human activity may be related to commercial shipping. The international community recognizes that underwater radiated noise (URN) from commercial ships may have both short and long-term negative consequences on marine life, especially marine mammals.
The URN Action Plan, which was approved by IMO's Marine Environment Protection Committee (MEPC 82), is aimed at addressing barriers to the uptake of the Revised URN Guidelines. Its goal is to further prevent and reduce underwater radiated noise from ships, and it will be reviewed and revised as necessary over time. Additionally, a three-year Experience Building Phase for the Revised Guidelines runs until MEPC 85 in 2026, with a possible two-year extension to develop best practices. This phase allows for practical experience to be gathered and best practices to be developed in applying the Guidelines.
As
part of ongoing awareness and capacity-building, the upcoming IMO GHG-URN Workshop taking place on 6-7 November 2025 presents an opportunity to promote technical dialogue and showcase progress in this area.
IMO has a process to designate
Particularly Sensitive Sea Areas (PSSAs), which are subject to associated protective measures such as mandatory ship-routeing systems.
There are currently
17 areas(plus two extensions) protected in this way, including those covering UNESCO World Heritage Marine Sites, such as the Great Barrier Reef (Australia), the Galápagos Archipelago (Ecuador), the Papahānaumokuākea Marine National Monument (United States), and the Wadden Sea (Denmark, Germany, Netherlands).
Designating Special Areas and PSSAs fully supports the SDG 14 target to increase coverage of marine protected areas.
Imagine you are on a cruise in the Caribbean, enjoying a refreshing drink. You finish it and dispose of the empty can into a nearby bin. But the crew on the ship knows that this small action has a big responsibility.
In the Wider Caribbean Region, including the Gulf of Mexico and Caribbean Sea, the ship can't just dispose the rubbish overboard. This area is a
Special Area under the MARPOL Convention, meaning stricter environmental rules are in place. Even food waste that hasn't been properly processed
can't be discharged into these waters.
The Wider Caribbean is one of
19 Special Areas worldwide, selected for their vulnerable ecosystems and heavy maritime traffic. Others include the Mediterranean Sea, Baltic Sea, and Antarctic waters. For instance, in the Antarctic, it's completely prohibited to discharge oil or garbage. (Read more about the
Polar Code here).
MARPOL's Annexes cover
various types of pollution, like oil, sewage, garbage, and air pollution, ensuring ships follow the proper waste management protocols.
Some
Particularly Sensitive Sea Areas (PSSAs) also include tailored protection measures for marine mammals. For example, the latest PSSA designated in the
North-Western Mediterranean Sea includes specific routing measures to reduce the risk of ship strikes with cetaceans during their migratory routes. These
PSSAs provide an extra layer of protection by not only restricting harmful activities but also implementing specific maritime practices aimed at preserving these critical habitats.
Ships are recycled when they reach the end of their operational lives. Safe recycling processes are vital to ensure the careful and secure handling of environmentally hazardous substances such as asbestos, heavy metals, hydrocarbons and ozone-depleting substances.
While the principle of ship recycling is sound, the working practices and environmental standards in ship recycling facilities varies from yard to yard. Global regulation will ensure safe working practices for those employed in ship recycling yards, along with consistent environmental standards.
The Hong Kong International Convention for the Safe and Environmentally Sound Recycling of Ships (the Hong Kong Convention) will enter into force on 26 June 2025. Its aim is to ensure that ships at the end of their operational lives are recycled safely and without posing unnecessary risks to human health and the environment. This milestone will mark a significant step toward more sustainable and responsible ship recycling practices worldwide.
To support Member States in the adoption of the Hong Kong Convention, IMO launched in 2015 the SENSREC Project, funded by the Governments of Norway and China to address the challenges prevalent in the ship recycling industry, particularly in South Asia. The SENSREC project works in collaboration with the Basel Convention Secretariat and the International Labour Organization (ILO), and provides technical assistance and training to developing countries, with the aim of upgrading conditions working conditions and environmental performance. You may find more information about the SENSREC project here.
Clean air and climate action
Pollution from the air – emissions from shipping – can directly
impact the ocean, making the ocean warmer and more acidic. IMO is actively working to
reduce the shipping industry's carbon footprint. The International Convention for the Prevention of Pollution from Ships (MARPOL), specifically Annex VI, sets limits on air pollution from ships, and energy efficiency measures to limit greenhouse gas emissions, which contribute to global climate change.
In 2023, IMO adopted the updated
2023 IMO Strategy on Reduction of GHG Emissions from Ships, aiming for
net-zero GHG emissions by or around
2050. The strategy includes
checkpoints for 2030 (20-30% reduction) and 2040 (70-80% reduction) compared to 2008 levels, along with a
40% reduction in carbon intensity by 2030.
The Strategy also sets a target for
alternative zero and near-zero GHG fuels to account for
at least 5% of shipping energy by 2030, striving for 10%. It proposes the development of a
marine fuel standard and a
GHG emissions pricing mechanism to accelerate the transition to low-carbon fuels.
To support implementation, IMO runs capacity-building programs and global projects.
Read more here.
IMO is leading
global partnership projects to address major ocean challenges, from reducing marine litter and cutting GHG emissions in shipping to combating the spread of invasive aquatic species.
Explore the IMO projects to protect the oceans below.
GEF-UNDP-IMO GloFouling Partnerships Project assists developing countries to prevent the transfer of aquatic invasive species through biofouling with a key collateral benefit of reducing greenhouse gas emissions from shipping through better biofouling management. Read more here
The "Accelerating Transfer of Environmentally Sound Technologies through demonstration pilots to reduce biofouling and related emissions" (TEST Biofouling) Project will assist developing countries to build their knowledge on control and management of biofouling. The TEST Biofouling project closely cooperates with and build on the achievements of the GloFouling Partnerships project. Read more here.
The OceanLitter Programme is home to a growing portfolio of multi-donor projects targeting the prevention and reduction of marine plastic litter from the maritime transport and fisheries sector. The GloLitter Partnerships Project is the first project of the Programme. Read more here.
SENSREC is a collaboration between the Government of Norway and IMO to support developing countries for the implementation of the Hong Kong International Convention for the Safe and Environmentally Sound Recycling of Ships. Read more here.
IMO is the secretariat for the Joint Group of Experts on the Scientific Aspects of Marine Environmental Protection (GESAMP), which is an inter-agency mechanism providing independent scientific advice on marine environmental protection into its ten sponsoring UN organizations. Read more here.
Safer ships protect the ocean
IMO regulations for the
safety of shipping and for maritime security help support the sustainable use of the oceans.
Maritime safety and security for sustainable use of the oceans
IMO's regulations ensure the safe and secure movement of ships, contributing to the sustainable use of the world's oceans:
Read more about IMO's maritime safety regulations
here.
Read more about IMO's work on maritime security
here.
Protecting the Arctic and Antarctic
Special measures under the
IMO Polar Code help protect the fragile ecosystems in polar waters, addressing the unique challenges faced by ships operating in these regions.
Read more here.
IMO works with the
United Nations to protect oceans and promote sustainable maritime practices, addressing challenges like marine plastic litter, GHG emissions, and invasive species, while supporting the UN's 2030 Agenda and Sustainable Development Goals.
IMO and UNCLOS
The
United Nations Convention on the Law of the Sea (UNCLOS), adopted in 1982, establishes comprehensive rules for the use of the world's oceans and their resources. It integrates traditional practices with new legal concepts and provides a framework for further development of ocean law. Read more about IMO and UNCLOS and download Implications of UNCLOS for IMO.
The
BBNJ Agreement, adopted on June 2023, focuses on the conservation and sustainable use of marine biodiversity in areas beyond national jurisdiction under the United Nations Convention on the Law of the Sea. IMO, with its expertise in international shipping regulations, continues to support the treaty's objectives, ensuring the sustainable use of the oceans. Read more here.
