Prevent pollution and reduce harmful emissions at sea
How the maritime industry should treat waste at sea and in ports, reduce oil and air pollution, and control ozone-depleting substances.
It is generally recognised that all businesses have a major role to play in preventing pollution and reducing releases of harmful emissions into the environment and this is particularly true of the shipping industry. The impact of pollution on fragile ecosystems is particularly severe in the marine environment, and to address this there is a substantial body of UK, European Union (EU) and wider international regulations related to environmental control, including comprehensive survey and certification requirements.
General requirements for pollution prevention in the marine environment
Most international regulations on marine pollution come from the 1973 International Convention for the Prevention of Pollution from Ships (MARPOL), which was updated in 1978. MARPOL was developed by the International Maritime Organization (IMO) and is aimed at preventing and minimizing pollution from ships - both accidental and from routine operations.
There have been a number of amendments to the Convention since it was first produced, and MARPOL now has six technical annexes covering marine pollution by:
- noxious liquid substances carried in bulk
- harmful substances carried in packaged form
- sewage from ships
- garbage from ships
- air pollution from ships
Survey and certification requirements for pollution prevention in the marine environment
The specific requirements for survey and certification of ships will depend upon the specific pollution prevention issue being considered. Some ships may only require a single survey at construction, while for others a renewal may be required every five years with additional mid-term surveys.
For more information on the regime for air emissions (including the requirements for engine NOx survey) see the section of this guide about air pollution and ozone-depleting substances.
Anti-fouling systems (AFS) are also the subject of the periodic survey regime. See the next section in this guide for further information.
Guidance on use of anti-fouling systems
Organotin compounds found in many AFS have been shown to have adverse effects on the ecology and on marine organisms. Their use is now prohibited in AFS for all ships, irrespective of size, and on fixed or floating platforms.
Ships longer than 24 metres but less than 400 gross tonnes must carry a Declaration, with supporting documentation, showing that the AFS used on the ship complies with the regulations. Ships of more than 400 gross tonnes must be surveyed on first use of an AFS, or when it is changed or substantially replaced. The ship’s Certificate must be endorsed accordingly.
Ships with no AFS which trade internationally must carry either a Declaration or Certificate stating specifically that no AFS has been used.
The sale and marketing of anti-fouling paints for marine use containing organotin compounds is prohibited within the UK and other EU states.
Prevention of marine pollution by garbage and sewage
The disposal of garbage and sewage from ships is a major environmental issue, and Annexes IV and V of the International Convention for the Prevention of Pollution from Ships were developed to address this.
Within the UK, Merchant Shipping (Prevention of Pollution by Garbage) Regulations 1998 were developed to address this and were updated in 2008 to reflect changes made to the system internationally. You can [download MGN 385 (M+F) Guidance on the Merchant Shipping (Prevention of Pollution by Sewage and Garbage from Ships) Regulations 2008(https://www.gov.uk/government/publications/mgn-385-prevention-of-pollution-by-sewage-and-garbage-from-ships-regulations-2008)
Under these Regulations:
- every ship of 12 metres or more must display placards informing crew and passengers about disposal requirements for garbage
- every ship of 400 gross tonnes or certificated for 15 passengers or more must have a garbage management plan and maintain a garbage record book
The Regulations also specify that vessels covered by the regulations must have at least one of the following:
- a sewage treatment plant which complies with the Merchant Shipping (Marine Equipment) Regulations 1999
- a sewage comminuting and disinfecting system, with facilities for temporary storage of sewage
- a holding tank for the retention of sewage which has sufficient capacity and has a visual indicator of the amount of its contents
Sewage that has been treated can be discharged anywhere at sea. Sewage that has been comminuted and disinfected can be discharged a minimum of three miles from the nearest land. Untreated sewage must be discharged no less than 12 nautical miles from the nearest land. In all the above cases the vessel must be proceeding at not less than 4 knots when making the discharge.
Other ships can opt into the provisions of the regulations and for smaller vessels guidance is provided by the Small Commercial Vessel and Pilot Boat Code of Practice. You can download MGN 280 (M) Small Vessels in Commercial Use for Sport or Pleasure, Workboats and Pilot Boats - Alternative Construction Standards
Port waste management planning
Port waste management is regulated by the Merchant Shipping and Fishing Vessels (Port Waste Reception Facilities) Regulations 2008, which includes requirements for vessels to:
- notify the port before arrival of waste onboard and the amounts to be offloaded
- offload all ship-generated wastes to port/terminal reception facilities, unless they have notified that they will be retaining wastes on board
- pay for the use of waste discharge facilities
In turn, harbour and terminal operators must provide adequate waste reception facilities, and must have in place a port waste management plan.
Although fishing vessels are exempt from notifying ports of their waste, and of paying a mandatory charge, they must land waste into the facilities provided by the port or directly to a waste contractor through a private contract.
Smaller vessels not governed by this regime are expected to dispose of their waste in an environmentally sound manner.
Vessels must make sure that waste from exhaust gas cleaning systems equipment is handled carefully and not discharged into ports, harbours or estuaries unless it is thoroughly documented that the waste streams will have no adverse impact on its ecosystem.
Air pollution and ozone-depleting substances
Air pollution from ships, and in particular the emission of sulphur and nitrogen compounds (SOx and NOx) and ozone-depleting substances (ODS) is strictly controlled by regulations that implement the International Convention for the Prevention of Pollution from Ships (MARPOL) and its various annexes and protocols. MARPOL Annex VI, which is specifically about air pollution, has 19 separate regulations, as well as a Code for controlling nitrogen oxide emissions. Annex VI is implemented in UK law through the Merchant Shipping (Prevention of Air Pollution from Ships) Regulations 2008 (as amended).
Volatile Organic Compounds (VOCs)
Control of VOCs at tanker terminals is left to individual terminals to reflect the variation in VOC impacts found between terminals. A port wishing to manage VOCs must contact the MCA and indicate:
- the size of tankers to be controlled
- the cargoes requiring vapour emission control systems
- the vapour emission control system to be employed
- operational practices
- the date the harbour or terminal would like the controls to start
The application must be submitted at least 18 months before the date that the harbour or terminal has applied for the VOC to be regulated.
The use of virgin hydro-fluorocarbons (HCFCs) is prohibited for maintenance and servicing from 1 January 2010 and for all HCFCs for maintenance and servicing from 1 January 2015. After 1 January 2015 HCFCs can continue to be used in existing installations provided that no maintenance or servicing takes place.
The use of ODS is not prohibited in systems and equipment installed before 19 May 2005.
Masters are required to record evidence of the changeover to low sulphur fuel in order to demonstrate compliance having entered a Sulphur Emission Control Area.
Masters of all ships subject to Annex VI must:
- keep records of fuel oil delivered to and used on the ship, with detailed information, on a bunker delivery note
- take and keep a sample of the fuel oil, signed by the supplier and the officer in charge of bunkering
Delivery notes must be kept on board for at least three years. The sample must be retained under the ship’s control until the fuel oil is used, or 12 months, whichever is longer.
Local suppliers of fuel oil for combustion purposes, delivered to and used on board ships, must register with the MCA.
Guidance on oil pollution and fuel oil sampling
The main international body of regulations to prevent pollution from ships is MARPOL. For more information, see the section of this guide on general requirements for pollution prevention in the marine environment. Annex I of the Convention, which is specifically aimed at preventing oil pollution, was subsequently supplemented by a separate IMO Convention on oil pollution preparedness, response and co-operation.
These Conventions have led to the development by the IMO of a manual on oil pollution, which provides practical information on preventing pollution and dealing with incidents.
The Manual can be bought from the IMO publications department. To order, call the IMO helpline on 020 7735 7611 or email firstname.lastname@example.org.
Oil Record Books
Every ship of 400 gross tonnes and above, other than an oil tanker, and every oil tanker of 150 gross tonnes and above, must keep and complete an Oil Record Book. It must be completed whenever any of the following operations take place in the ship:
- ballasting or cleaning of oil fuel tanks
- discharging ballast or cleaning water from oil fuel tanks
- disposing oily residues (sludge)
- discharging overboard bilge water which has accumulated in machinery spaces
Oil tankers will need to record extra operations including loading, unloading and transferring oil cargo.
There are detailed construction requirements for new ships within the MARPOL annex which are particularly relevant to oil tankers but impact on other vessels as well.
Pollution prevention for fishing and inland waterway vessels
The cumulative effect of relatively small-scale pollution from garbage, bilge washing and catering waste causes a range of problems, as does lost fishing gear. Some of this material does not degrade easily, and can cause injuries to marine life, as well as propeller fouling and intake blockages.
To prevent these problems, operators of fishing vessels should:
- have onboard procedures that minimise the accidental loss of fishing gear at sea
- bring garbage and debris ashore for disposal
- become involved in the port’s waste management plan and in particular raise any inadequacies with the port authorities
Inland waters in the UK are categorised into one of four groups. In outline, these are:
- narrow rivers and canals with a general depth of less than 1.5 metres
- wider rivers and canals with a general depth of over 1.5m, and significant wave heights of less than 0.6 metres
- tidal rivers and estuaries and large lakes with significant wave heights of less than 1.2 metres
- tidal rivers and estuaries with significant wave heights of less than 2.0 metres
Operators of vessels in these waters should comply with local bylaws relating to the discharge of waste water and dispose of rubbish at suitable shore facilities. Sanitation systems capable of discharging sewage must not be fitted unless they can be sealed or rendered inoperable. Sealed sanitation systems must be in accordance with the BS MA101:1986 Specification for toilet retention and re-circulation systems for the treatment of toilet waste.
Oil-tight trays must be fitted under every engine and gearbox to prevent oil leaks. No fixed bilge pump should draw from an oil-tight area.
Further information on preventing pollution at sea
As well as guidance on specific types of vessel, more general information on measures to prevent pollution is available from the MCA and the IMO.
Full information on UK regulations and procedures can be found in the MCA Master’s guide to the UK flag. Download the Master’s guide to the UK flag
020 7735 7611
Download Marine Information Note 377 (M+F) Guidance of the Completion of the Notification Form Required under the Merchant Shipping and Fishing Vessels (Port Waste Reception Facilities) Regulations 2003 from the MCA website (PDF, 75KB)