MARPOL environment protection regulations for yachts

20 January 2015• Written by Paolo Moretti, RINA
Tribù's build took the environment into account. The hull was hand-painted, not sprayed, using TBT-free bottom paint.

Naturally, yacht owners wish for a beautiful environment in which to enjoy their yacht and, because of this, many are prepared to invest in green technologies to ensure they achieve the highest levels of efficiency with the lowest possible environmental impact. At the same time, several international conventions deal with the protection of the marine environment. Among these are

  • The MARPOL Convention , governing marine and air pollution;
  • The Anti-fouling System Convention , which bans the use of anti-fouling systems containing harmful substances;
  • The International Convention for the Control and Management of Ships Ballast Water and Sediments , which aims to minimise the transfer of harmful aquatic organisms and microbes from one geographical area to another. (This is not in force yet); and
  • The Ships Recycling Convention , which deals with the recyclability of ships and recycling facilities ashore (that is also not yet in force).In addition to these international rules, some nations have adopted extra requirements for navigation in their local waters. For example, the Baltic and North Sea are Sulphur Emission Control Areas; Alaska has stricter requirements on sewage, grey water and oil pollution; California has its own legislation on diesel engines’ emissions; and many areas in the Mediterranean can only be accessed by certain ships and require potential polluting substances to be retained on board.

Marine protection

The first international instrument to protect the marine environment from ships’ pollution was the MARPOL Convention – in full, the International Convention for the Prevention of Pollution from Ships – which came into force in 1983.

For the purpose of MARPOL, ‘ships’ are vessels of any type operating in the marine environment, including yachts.

The MARPOL Convention is comprised of six annexes covering marine and air pollution. Four of these annexes are applicable to yachts in private and commercial service.

Annex I

This annex deals with oil pollution from machinery, and mainly regulates the minimum production of oil residues and oily water, the separation of oil from water, and discharge of oil at sea. It is applicable to all yachts.

Yachts having a gross tonnage equal to, or over 400GT, and engaged in international voyages need to be provided with an International Oil Pollution Prevention Certificate, valid for five years and subject to annual, intermediate and renewal surveys.

Annex IV

This deals with sewage. It is applicable to yachts with a gross tonnage equal to or over 400GT or carrying more than 15 people.

It came into force in 2003 with the latest revision in 2005. Yachts were obliged to comply by September 2008. However, many yachts still do not have this certification. The certificate is valid for five years and subject to renewal.

In order to meet the provisions of the annex, owners can either send sewage ashore or discharge it overboard, when more than 12 miles offshore, or equip the yacht with an approved sewage treatment plant capable of discharging treated sewage with certified effluent standards.

If an approved treatment system is provided, then the treated sewage can be discharged at any distance from the nearest land, provided that the yacht is proceeding at a speed of over four knots and that no additional national requirements are applicable in the area.

Annex V

This entered into law in 1988 and deals with garbage and determines which wastes can be discharged at sea, and the distance from land it needs to be.

No international certificates are required but yachts having a gross tonnage equal to or over 400GT, or are certified to carry 15 or more people, need to carry a garbage management plan with written procedures for collecting, storing, processing and disposing of garbage.

They also need a record book where discharge at sea, discharge to reception facilities, incineration and accidental discharge is recorded.

Annex VI

This entered into force in 2005 and regulates emissions, including:

  • Ozone-depleting substances : Restriction of the use of halon in fire-fighting systems and some pollutant gases in refrigerating systems.
  • Nitrogen oxides (NOx) : The production of these substances is mainly related to the engines. All diesel engines (except those for emergency use and installed on lifeboats) with an output of more than 130kW, installed on ships built after 1 January 2000, are certified in accordance with the NOx Emission Technical Code and provided with the relevant certification and technical files.
  • Sulphur dioxide (SO2) : The emission of this substance is directly related to the quality of the fuel burnt and the quantity of sulphur content: it should not exceed 4.5%. In particularly sensitive areas such as Baltic and North Sea areas, called Sulphur Emission Control Areas, only fuels having a maximum sulphur content of 1.5% can be used.
  • Volatile organic compounds : These are mainly produced by paint application.
  • Incinerator exhausts : All yachts having a gross tonnage equal to or over 400GT must hold an International Air Pollution Certificate, which is valid for five years and subject to periodical renewal surveys.
The Mochi Craft Long Range has been designed with a 'zero emission mode' hybrid propulsion system.

MARPOL amendments

The MARPOL Convention is always evolving and several amendments are coming into force, often with retroactive application.

Annex I

All yachts that were delivered after 1 August 2010, with a fuel tank capacity exceeding 30 cubic metres, need to be protected by a double hull to prevent accidental spillage in case of collision or grounding.

Annex IV

More stringent effluent standards have been introduced by IMO Resolution MEPC 159(55) to be applied to equipment installed on or after 1 January 2010.

Annex VI

Stricter requirements on the NOx emission limits are coming into force between 2011 and 2016. The global sulphur cap was reduced from 4.5% to 3.5%, effective from 1 January 2012, and will be further reduced to 0.5%, effective from 1 January 2020.

Greenhouse gases

Considering that 4 per cent of the world’s total carbon dioxide emissions come from ships, the International Maritime Organisation (IMO) is considering making a ruling on this subject.

As these emissions are mainly related to fuel consumption, the industry has spent great effort looking at energy-saving features and operations, such as:

  • Optimised hull design,
  • High-efficiency and alternative propulsion systems,
  • Regular cleaning of hull and propellers,
  • Optimisation of generators’ load sharing,
  • Waste minimisation in the electrical power supply,
  • Management of air-conditioning systems,
  • The correct use of stabilisers, and
  • Crew training.

Other mandatory rules

There are several other mandatory rules, some applicable depending on the gross tonnage and others according to the number of persons the boat is certified to carry.

In addition, there are different national regulations and there is a trend towards stricter international mandatory requirements over the next few years with retroactive application to existing vessels.

It is therefore advisable for any owner who is starting a new construction or a major refit to make sure his yacht will be certified in compliance with the strictest international and national regulations.

Voluntary certifications

Many owners and designers want to go beyond the compulsory requirements and introduce innovative technologies. This is where voluntary certification comes in.

Some classification societies have recently developed internal standards to certify the environmental sustainability of ships and yachts. RINA, during the 1990s, was the first organisation to develop a set of rules specifically designed for cruise ships operating in sensitive areas such as Alaska or the Baltic Sea.

RINA has also developed a new standard applicable to pleasure vessels, the Green Plus Yacht, and an increasing number of superyachts comply with them.

The key criteria of Green Plus are that a yacht should reflect a significant investment in design solutions, on board equipment and operational procedures aimed at contributing to an environmental performance above the minimum levels required by the IMO regulations.

Green Plus specifically identifies 12 pollution sources concerning emissions into the sea and the air, which are:

  • Oil from machinery spaces,
  • Sewage,
  • Grey water,
  • Ballast water,
  • Garbage,
  • Ozone-depleting substances,
  • Greenhouse gases,
  • NOx, SOx, CO2 and particulates, and
  • Building materials. The environmental impact caused by each of these sources can be reduced by adopting solutions and procedures identified in the Green Plus scheme. Each has an associated score that has been defined by taking into account the difficulty of applying the solution chosen. The sum of all scores is the ‘yacht environmental index’.

There are three levels of Green Plus certification: Green Plus Yacht, Green Plus Yacht Gold and Green Plus Yacht Platinum. The different levels of merit reward those projects that have made significant investments in terms of green technologies.

Thinking green at the design stage will not only guarantee sailing on an environmentally friendly yacht, but also means the yacht can be built to comply with the strictest international and local environmental regulations, and offers the possibility to introduce highly innovative technologies, and the adoption of fuel-consumption reduction solutions.

Being green is the future for yachting – take heed!

Originally published: July 2010.

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