The International Convention for the Prevention of Pollution from Ships (MARPOL)
Divided into 6 annexes:
I Oil
II Noxious Liquid Substances in Bulk
III Harmful Substances in Packaged Form
IV Sewage
V Garbage
VI Air Pollution
Annex I – Regulations for the Prevention of Pollution by Oil
Entered into force 2 October 1983 and applies to all ships subject to MARPOL (400grt and above, 150grt for tankers).
Discharge of Oil is prohibited in some areas and severely restricted in others.
Ships are subject to initial, annual, intermediate and renewal surveys plus additional surveys after important repairs or renewals are made.
An International Oil Pollution Prevention (IOPP) Certificate will be issued after initial and renewal surveys and is usually valid for 5 years (one of the 9 main certificates subject to the Harmonised System of Survey and Certification).
Double Hulls or Double Bottoms are required to protect oil fuel tanks and the size of each tank is limited to a maximum of 2,500m³.
Oil Discharge Monitoring and Control System (ODMCS) may need to be fitted to the discharges of certain ships. It must activate automatically when discharge occurs and record the date, time, volume and oil content. These records must be retained for at least 3 years.
En route means that the ship is underway at sea on a course or courses, including deviation from the shortest direct route, which, as far as practicable for navigation purposes, will cause any discharge to be spread over as great an area of the sea as is reasonable and practicable.
From the nearest land means from the baseline from which the territorial sea of the territory in question is established in accordance with international law.
Requirements for Ships discharging machinery space bilge water
• The ship is en route
• Ships 400-10,000grt must have oil filtering equipment for discharges limiting oil content to no more than 15ppm
• Ships over 10,000grt must also have oil filtering equipment with a 15ppm limit but also an alarm and automatic shut-off to ensure that this is not exceeded
• Tankers must ensure that none of this discharge originates from their cargo pump rooms and that it doesn’t contain cargo residues
• In special areas ships may discharge as long as they remain below the 15ppm limit but all ships over 400grt must have an alarm and automatic shut-off
Except no ship may discharge in the Antarctic special area
Special Areas under Annex I:
Mediterranean Sea, Baltic Sea, Black Sea, Red Sea, Gulfs Area, Gulf of Aden, Antarctic Area (no discharge), North West European Waters, Oman area of the Arabian Gulf, Southern South African Waters
Records and Documents on board any ship under Annex I:
• International Oil Pollution Prevention (IOPP) Certificate
• Oil Record Book Part I – Machinery Space Operations
• Instruction or Operational Manual for Oily Water Separator and Oil Filtering Equipment
• Shipboard Oil Pollution Emergency Plan (SOPEP)
The Oil Record Book Part I – Machinery Space Operations shall contain records of operations or events which may have resulted in pollution (eg loading, bunkering, spill on deck) in English, French or Spanish. The entry should be completed by the person responsible for overseeing the operation and the Captain must sign each page. The record must be retained for at least 36 months (3 years).
The Shipboard Oil Pollution Emergency Plan (SOPEP) shall contain the reporting procedure for pollution incidents, the list of authorities or persons to be contacted, a detailed description of the immediate actions to be taken to reduce or control discharge of oil, details of the procedures and point of contact on ship for co-ordinating shipboard action with national and local authorities.
Requirements for Oil Tankers discharging oily water from cargo areas
• En route
• More than 50NM from nearest land
• Not in a special area
• Instantaneous rate of discharge of the oil content is less than 30 litres per nautical mile
• Content is less than 1/30,000th of the total quantity of the cargo which the reside formed a part.
• Discharged through ODMCS with alarm and automatic shut-off
Additional Records and Documents on board any Tanker under Annex I:
• Oil Record Book Part II – Cargo/Ballast Operations
• Loading and Damage Stability Information Book
• Oily Discharge Monitor Operational Manual
• Crude Oil Washing (COW) Operations and Equipment Manual
• Clean Ballast Tank* Operation Manual
*A Clean Ballast Tank is a tank which has been previously used for cargo but has been cleaned such that no oil residue would be evident if discharged into still water from a stationary vessel. A Segregated Ballast Tank is one that is only ever used for water ballast.
The Oil Record Book Part II – Cargo/Ballast Operations records operations such as loading of oil cargo, internal transfer of oil cargo, ballasting of cargo tanks and dedicated clean ballast tanks, cleaning of cargo tank including Crude Oil Washing, discharge of water from slops tanks, the closing of valves to stop operations or to isolate Clean Ballast Tanks, disposal of residues as well as any failure of the ODME.
Ships Emergency Response Service (SERS)
Tankers over 5,000dwt must have prompt access to shore-based computer programs for damage stability and residual structural strength calculations.
Annex II – Regulations for the Prevention of Pollution by Noxious Liquid Substances in Bulk
Entered into force 2 October 1983 and applies to chemical tankers, product tankers, liquefied gas carriers and any other vessels carrying NLS other than oil in bulk.
Ships under Annex II are subject to Initial, Annual, Intermediate and Renewal Surveys.
They will be issued with an International Pollution Prevention Certificate for the Carriage of Noxious Liquid Substances in Bulk (NLS Certificate), usually valid for 5 years (Harmonised System of Survey and Certification – see also International Certificate of Fitness for the Carriage of Dangerous Chemicals in Bulk or the Certificate of Fitness for the Carriage of Dangerous Chemicals in Bulk (IBC/BC).
Liquid substances must be classified into one of four categories before transport:
X – Present a major hazard to either marine resources or human health if discharged into the sea.
Y – Present a hazard to either marine resources or human health or cause harm to amenities or other legitimate uses of the sea if discharged into the sea.
Z – Present a minor hazard to either marine resources or human health if discharged into the sea.
OS – Present no hazard to either marine resources or human health and cause no harm to amenities or other legitimate uses of the sea if discharged into the sea.
NLS of categories X, Y and Z often pose a safety hazard as well as a pollution hazard and are therefore listed in the International Code for the Construction and Equipment of Ships carrying dangerous Chemicals in Bulk (IBC Code). This list can be used like the Dangerous Goods List in the IMDG Code.
Discharge Requirements:
These vary according to vessel type as follows:
Category X – The contents of tanks containing category X cargos must be prewashed prior to leaving port and the residues pumped ashore until the concentration of the effluent is 0.1% by weight or less. The concentration must be confirmed by analysis of the discharge samples taken by a Marine Surveyor. Once the required concentration levels are met the remaining tank washing are to be discharged ashore to a reception facility until the tanks are empty. Water subsequently added to a category X tank may be discharged into the sea under the following conditions:
- The ship is proceeding en route at a speed not less than 7kts.
- The discharge is below the waterline
- The ship is more than 12nm from the nearest land
- The depth of water is not less than 25m.
Category Y – The tanks must be prewashed prior to leaving port and any residues discharged to a shore reception facility. Water subsequently added to the tank can be discharged if:
- The ship is proceeding en route at a speed not less than 7kts.
- The discharge is below the waterline
- The ship is more than 12nm from the nearest land
- The depth of water is not less than 25m.
- The ship is proceeding en route at a speed not less than 7kts.
- Concentration of the substance in the ships wake is less than 1ppm.
- Volume of discharge does not exceed 1m3 or 1/30,000th of the tank capacity whichever is greater.
- The discharge is below the waterline
- The ship is more than 12nm from the nearest land
- The depth of water is not less than 25m.
Special Areas under Annex II:
The Antarctic Area – Not discharge permitted under any circumstances.
Annex III – Regulations for the Prevention of Pollution by Harmful Substances in Packaged Form
Entered into force 1 July 1992 and applies to all ships carrying harmful substances in packaged form, or in freight containers, portable tanks, road tanks or wagons. Harmful substances any substances identified as Marine Pollutants the IMDG Code.
The annex contains general requirements for the issuing of detailed standards on packing, marking, labelling, documentation, stowage, quantity limitations, exceptions and notifications.
Any substances in the Dangerous Goods List which are marked with a ‘P’ in the ‘subsidiary risk(s)’ columnare a Marine Pollutant. Part 9 of the IMDG code details the requirements for transporting marine pollutants.
Refer to the IMDG article for more information on this code and its contents.
No annex 3 goods should be discharged into the sea unless absolutely necessary for the safety of life or the ship. In such circumstances a detailed log of events must be maintained.
There is No Special Areas in Annex III because no discharge is permitted outside of an emergency. There is also no annex III specific certificate but your ship will be issued with a Document of Compliance for IMDG.
Annex IV – Regulations for the Prevention of Pollution by Sewage
Applies to vessels over 400grt or any carrying more than 15 persons
Ships are subject to initial and renewal surveys to receive an International Sewage Pollution Prevention Certificate (ISPP) valid for up to 5 years
Ships must be equipped with either:
- A sewage treatment plant
- A sewage comminuting and disinfecting system
- A sewage holding tank
Requirements for ships discharging sewage:
Discharge of sewage without specified restriction is permitted if an approved sewage treatment plant is in use.
Discharge of sewage may occur at a distance more than 3 miles from land if it has been treated or comminuted and disinfected.
Discharge of untreated sewage is permitted not less than 12 miles from nearest land and if sewage has been stored in a holding tank then the discharge must be at a moderate rate when the ship is en route and steaming at least 4kts. The discharged effluent should not discolour the surrounding water or contain visible solids.
Special Areas under Annex IV:
The Baltic Sea – From 1st January 2013 the discharge of sewage from passenger ships is prohibited unless an approved sewage treatment plant capable of reducing nutrients is installed. Passenger ships may discharge ashore to reception facilities.
This special area however will only take effect upon receipt of sufficient notifications on the existence of adequate reception facilities from Parties to MARPOL Annex IV whose coastlines border the relevant special area.
Annex V – Regulations for the Prevention of Pollution by Garbage
Applies to all vessels (even if they aren’t required to keep records). All vessels of 12m or more must display placards informing crew and passengers of disposal requirements.
Vessels over 400grt or certified to carry 15 or more passengers must have:
– Garbage Management Plan containing written procedures for minimizing, collecting, storing, processing and disposing of garbage in accordance with IMO guidelines and written in the working language of the crew
– Garbage Record Book containing details of all discharge and incinerator operations and any accidental losses. Books must be preserved for 2 years after the final entry
Flag and Port State inspections will ensure these are in place but no certificate is issued under Annex V.
Garbage is split into 9 categories:
1. Plastics
2. Food Wastes
3. Domestic Wastes (from accommodation eg drinking bottles, papers, cardboard etc)
4. Cooking Oil
5. Incinerator Ashes
6. Operational Wastes (solid waste and slurries created by maintenance or operations, also wash water containing cleaning agents or additives that are ‘Harmful Substances’ for the marine environment as per MARPOL Annex III).
7. Cargo Residues (whatever cannot be removed by normal unloading equipment)
8. Animal Cargoes
9. Fishing Gear
Discharge Requirements
Requirements for vessels discharging Food Wastes:
Ground or Comminuted (enough to pass through a 25mm mesh screen)
– Vessel is en route
– At least 3 miles from nearest land (12 miles in special areas)
Not Ground or Comminuted
– Vessel is en route
– Not in a special area
– At least 12 miles from nearest land
Offshore platforms more than 12 miles from nearest land and vessels within 500m of such platforms may only discharge ground or comminuted food wastes.
Requirement for vessels discharging Cargo Residues:
Cargo Residues not contained in wash water (eg sweepings)
– Vessel is en route
– Not in a special area
– As far as practicable from land
– At least 12 miles from nearest land
Cargo Residues contained in wash water
– Vessel is en route
– As far as practicable from land
– At least 12 miles from nearest land
Offshore platforms more than 12 miles from nearest land and vessels within 500m of such platforms may not discharge Cargo Residues.
Requirements for vessels discharging Animal Carcasses:
– Carcasses must be split or treated to ensure they sink immediately
– Vessel is en route
– Not in a special area
– As far as possible from land
– At least 100 miles from nearest land
– In deepest available water
Offshore platforms more than 12 miles from nearest land and vessels within 500m of such platforms may not discharge Animal Carcasses.
Wash Water containing cleaning agents and additives that are not harmful to the marine environment may be discharged anywhere if it was used to clean the deck or external surfaces of a vessel. If it was used to clean cargo holds it must be discharged when the vessel is en route and more than 12 miles from nearest land in special areas.
Offshore platforms more than 12 miles from nearest land and vessels within 500m of such platforms may not discharge Wash Water.
Other Garbage – Annex V prohibits the disposal of all other garbage with following exceptions:
- To preserve life or the safety of the vessel
- Accidental losses following damage to the ship or its equipment
- Accidental loss of synthetic fishing nets
Special Areas under Annex V:
Mediterranean Sea, Baltic Sea, Black Sea, Red Sea, Gulfs Area, North Sea, Antarctic Area, Wider Caribbean Region
(Summary of discharge restrictions)
Annex VI – Regulations for the Prevention of Air Pollution by Ships
The Annex applies to all ships but certain regulations make exceptions
Ships over 400grt will be issued with an International Air Pollution Prevention (IAPP) Certificate and an International Energy Efficiency (IEE) Certificate
Instead of Special Areas there are a number of Emission Control Areas (ECAs) where limits are imposed on the amount of Nitrogen Oxides, Sulphur Oxides or Particulate Matter in engine exhaust gases:
Baltic Sea (SOx)
North Sea (SOx)
North America (NOx, SOx and Particulate Matter)
United States Caribbean Sea Area (NOx, SOx and Particulate Matter)
The Annex aims to control Air Pollution from:
Ozone-Depleting Substances
Nitrogen Oxides from diesel engines (NOx)
Sulphur Oxides from fuels containing sulphur (SOx)
Volatile Organic Compounds and Hydrocarbon vapours from cargo spaces
Incinerator exhaust
Poor quality fuels
Poor energy efficiency
Ozone-Depleting Substances
The Annex forbids the installation of any firefighting or refrigeration system using Ozone-Depleting Substances (OSDs). OSDs include Halon and CFCs. Existing systems may still be used and recharged but an OSD Record Book must be kept detailing any discharge, recharge or maintenance, entries into existing logs may satisfy this requirement.
Nitrogen Oxides (NOx)
The Annex prescribes limits for the Nitrogen Oxide content of engine exhaust in ships built on or after 1 January 2000. The vessel’s engines will be surveyed for levels of Nitrous Oxide emissions and an Engine International Pollution Prevention (EIAPP) Certificate will be issued for each one individually.
Ships built in 2000-2011 must meet the Tier I standards for NOx emissions
Ships built in 2011-2016 must meet a more stringent standard
Tier III will apply to ships built on or after 1 January 2016 when operating in ECAs
Sulphur Oxides (SOx)
The Annex prescribes limits for the Sulphur Content and particulate matter emissions. There are two standards, depending on whether the ship is in an Emission Control Area (ECA):
Outside an ECA – not exceeding 3.5%m/m (hopefully reducing to 0.5% in 2020)
Inside an ECA – not exceeding 0.1%m/m
Ships wishing to save money may carry two grades of fuel to satisfy these requirements. This would necessitate a change of fuels long enough before entering an ECA that all the lower grade fuel in the lines has been burned.
Volatile Organic Compounds (VOCs) and Hydrocarbon Vapours
Tankers liable to release these during cargo loading require a Vapour Emission Collection System. Crude oil tankers must have a VOC Management Plan to minimise emissions during loading, transport and discharge of cargo.
Incinerator Exhaust
The burning of certain substances is prohibited including cargo residues and garbage containing heavy metals.
