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These Guidelines have been developed to assist with the maintenance of the shipboard oil pollution plan. Such plan shall be effective if it is carefully tailored to the particular ship for which it is intended. Certain aspects of the plan would be common for all company’s ships but when dealing with equipment and particulars of tanks etc only ship specific information is to be used.

Emergency plans are required by chapter V – Regulation 37 of Annex I of the MARPOL 73/78.

This requires all oil tankers over 150 grt carrying oil in bulk, either as cargo or bunkers, and every other vessel over 400 grt, to have a contingency plan, referred to as a SOPEP.

Why have a plan

The Plan is available to assist personnel in dealing with an unexpected discharge of oil. Its primary purpose is to set in motion the necessary actions to stop or minimize the discharge and to mitigate its effects. Effective planning ensures that the necessary actions are taken in a structured, logical and timely manner.

The Plan goes beyond providing for operational spills. It includes guidance to assist the master in meeting the demands of a catastrophic discharge, should the ship become involved in one.

The need for a predetermined and properly structured Plan is clear when one considers the pressures and multiple tasks facing personnel confronted with an emergency situation. In the heat of the moment, lack of planning will often result in confusion, mistakes and failure to advise key people.

Delays will be incurred and time will be wasted; times during which the situation may well worsen. As a consequence, the ship and its personnel may be exposed to increasing hazards and greater environmental damage may occur.

What kind of plan

The Plan is.

  • Realistic, practical, and easy to use.
  • Understood by ship management personnel, both on board and ashore
  • Evaluated, reviewed and updated regularly.

Language used in the plan

It is available in the working language of the master and officers. A change in the master and officers which brings about an attendant change in their working language would require the issue of the Plan in the new language.

Contents of the Plan

The Plan consists at least of the following:

  • The procedure to be followed by the master or other persons having charge of the ship to report an oil pollution incident.
  • The list of authorities or persons to be contacted in the event of an oil pollution incident.
  • A detailed description of the action to be taken immediately by persons on board to reduce or control the discharge of oil following the incident.
  • The procedures and point of contact on the ship for coordinating shipboard activities with national and local authorities in combating the pollution.
  • The procedures to ensure that the medial is handled correctly

Reporting and Contact Lists

The Plan provides clear, concise guidance to enable the master to determine when a report to the coastal State is required.

The Plan gives the master guidance to evaluate a situation which, though not involving an actual discharge, would qualify as a probable discharge and thus require a report. In judging whether there is such a probability and whether a report should be made, the following factors, as a minimum, should be taken into account

  • the nature of the damage, failure or breakdown of the ship, machinery or equipment
  • ship location and proximity to land or other navigational hazards
  • weather, tide, current and sea state
  • traffic density

It is impracticable to lay down precise definitions of all types of situations involving probable discharge which would warrant an obligation to report. As a general guideline, the master should make a report in cases of

  • Damage, failure or breakdown which affects the safety of ships; examples of such situations are collision, grounding, fire, explosion, structural failure, flooding, cargo shifting
  • Failure or breakdown of machinery or equipment which results in impairment of the safety of navigation; examples of such incidents are failure or breakdown of steering gear, propulsion, electrical generating system, essential ship borne navigational aids.

The Plan specifies, in appropriate detail, the procedure for making the initial report to the coastal State. Supplementary or follow-up reports should as far as possible use the same format.

The Plan contains a List of Persons to be contacted if the ship is involved in a pollution incident with both coastal State or port contacts and ship interest’s contacts.

When compiling contact lists, due account must be taken of the need to provide 24-hour contact information and to provide alternates to the designated contact. These details must be routinely updated to take account of personnel changes and changes in telephone, telex and telefax numbers.

Clear guidance should also be provided regarding the preferred means of communication (telex, telephone, telefax INMARSAT etc.).

In order to expedite response and minimise damage from a pollution incident, it is essential that appropriate coastal States be notified without delay. Contact details of such authorities must be available in the Plan.

The Plan includes as an appendix the list of agencies or officials of administrations responsible for receiving and processing reports as developed and updated by the Organisation.

For ships in port, notification of local agencies will speed up the response. The Plan should require the master to obtain details concerning local reporting procedures upon arriving in port.

The Plan provides details of all parties with an interest in the ship to be advised in the event of an incident. This information provided is in the form of a contact list. When compiling such lists, it should be remembered that in the event of a serious incident, ship’s personnel will be fully engaged in saving life and taking steps to control and minimise the effects of the casualty.

Highlighting duties and responsibilities

It is important that the Plan clearly specifies who will be responsible for informing the various interested parties such as cargo owners, insurers and salvage interests. It is also essential that both the ship’s Plan and its company’s shore side Plan are coordinated to guarantee that all parties having an interest are advised and that duplication of reports is avoided.

Ships Staff duties (Muster list)

Ship personnel will almost always be in the best position to take quick action to reduce or control the discharge of oil from their ship. The Plan should provide the master with clear guidance on how to accomplish this for a variety of situations. The Plan should not only outline action to be taken, but it should also identify who on board is responsible so that confusion during the emergency can be avoided.

Spill Handling

The Plan provides the master with guidance to address the following

Operational spills

The Plan outlines the procedures for removal of oil spilled and contained on deck. This may be through the use of on-board resources or by hiring a clean-up company. In either case the Plan should provide guidance to ensure proper disposal of removed oil and clean-up materials.

Pipe leakage

The Plan provides specific guidance for dealing with pipe leakage.

Tank overflow

Procedures for dealing with tank overflows are included.

Alternatives such as lowering cargo or bunkers back to empty or slack tanks or readying pumps to transfer the excess ashore should be outlined.

Hull leakage

The Plan provides guidance for responding to spillage due to

Suspected hull leakage.

This may involve guidance on measures to be taken to reduce the head of cargo in the tank involved either by internal transfer or discharge ashore. Procedures to handle situations where it is not possible to identify the specific tank from which leakage is occurring should also be provided. Procedures for dealing with suspected hull fractures should be included and they should carry appropriate cautions regarding attention to the effect corrective actions may have on hull stress and stability.

Spills resulting from casualties

Each of the casualties listed below should be treated in the Plan as a separate section comprised of various checklists or other means which will ensure that the master considers all appropriate factors when addressing the specific casualty. These checklists must be tailored to the specific ship. In addition to the checklists, specific personnel assignments for anticipated tasks like Groundings, Fire/Explosion, Collision, Hull failure, Excessive list etc must be identified.

Priority Actions, Stability and Stress Considerations, Lightening

The Plan should provide the master with guidance concerning

Priority actions

These apply to a wide range of casualties. The Plan should provide ship-specific guidance to the master concerning safety of personnel and the ship, bottom damage

Stability and stress considerations

Great care in casualty response must be taken to consider stability and stress when taking actions to mitigate the spillage of oil or to free the ship if aground. The Plan should provide the master with detailed guidance to ensure that these aspects are properly considered. Contact may have to be made with the owner or operator, Classification societies, independent organisations or other entity in order that information can be provided so that damage stability and damaged longitudinal strength assessments may be made. The Plan should clearly indicate who the master should contact in order to gain access to these facilities.

Where appropriate the Plan should provide a list of information required for making damage stability and damaged longitudinal strength assessments.

Lightening or transfer of cargoes

Should the ship sustain extensive structural damage, it may be necessary to transfer all or part of the cargo to another ship. The Plan should provide guidance on procedures to be followed for ship-to-ship transfer of cargo. A copy of such company procedures for ship-to-ship transfer operations should be kept with the Plan. The Plan should address the need for co-ordinating this activity with the coastal State, as such operation may be subject to its jurisdiction.

Plans and drawings

Certain plans, drawings and ship-specific details such as a layout of a general arrangement plan, a tank plan, etc., should be appended. The Plan should show where current cargo, bunker and ballast information, including quantities and specifications, are available.

National and Local Co-ordination

Quick, efficient co-ordination between the ship and coastal State or other involved parties becomes vital in mitigating the effects of a pollution incident. The Plan should address the need to contact the coastal state for authorization prior to undertaking mitigating actions. Some coastal states have agencies that take charge of response immediately and subsequently bill the owner for the cost. In other coastal States, responsibility for initiating response is placed on the shipowner. In the case of the latter the Plan will require greater detail and guidance to assist the master with organizing this response.

Response Equipment

Some ships may carry on board equipment to assist in pollution response. The type and quantity of this equipment may vary widely. The Plan should indicate an inventory of such equipment, if carried. It should also provide directions for safe use and guidelines to assist the master in determining when such use is warranted. When such equipment is carried, the Plan should establish the responsibilities of the personnel for its deployment, supervision and maintenance. In order to ensure safe and effective use of such equipment, the Plan should also provide for crew training in the use of the equipment.

The Plan should include a provision that no chemical agent should be used for response to pollution on the sea without authorisation of the appropriate coastal State and that such authorisation should also be requested, when required, for use of containment or recovery equipment.

Media Handling

The owners may want to include in the plan guidance for the master in dealing with the distribution of information to the news media. Giving of such information should normally be undertaken by the owners ashore as otherwise valuable time of the ships staff may be taken up in the same. Master should direct such inquires to the owners or his designated officer.


As with any other incident these incidences will eventually involve liability, compensation and reimbursement issues. The owners may therefore want to include in his Plan guidance for the keeping of appropriate records of the pollution incident and on the process of alerting the P&I clubs. Guidance on collecting of samples of spilled oil as well as that carried on board may also be provided. See guide to mariners for collecting evidence.

Plan Review

Regular review of the Plan by the owner, operator or master is recommended to ensure that the specific information contained therein is current.

The Plan should be reviewed by the owner or operator at least yearly to capture changes in local law or policy, contact names and numbers, ship characteristics, or company policy;

Testing and realistic drills of the Plan

The Plan will be of little value if it is not made familiar to the personnel who will use it. Regular exercises will ensure that the Plan functions as expected and that the contacts and the communications specified are accurate. Such exercises may be held in conjunction with other shipboard exercises and appropriately logged. Where ships carry response equipment, hands on experience with it by crew members will greatly enhance safety and effectiveness in an emergency situation. Procedures for training and exercise may be defined.

Fate and behaviour of oil in the marine environment

Oil transformation in the marine environment starts developing from the first seconds of oil’s contact with seawater. The progression, duration, and result of these transformations depend on the

  • Properties and composition of the oil.
  • Parameters of the actual oil spill
  • Environmental conditions.

The main characteristics of oil transformations are their dynamism, especially at the first stages, and the close interaction of physical, chemical and biological mechanisms of dispersion and degradation of oil components up to their complete disappearance as original substances.

A marine ecosystem destroys, metabolizes and deposits the excessive amounts of hydrocarbons, transforming them into more common and safer substances.

Physical spreading of oil

The distribution of oil spilled on the sea surface occurs under the influence of gravitation forces. It is controlled by oil viscosity and the surface tension of water. Only ten minutes after a spill of 1 ton of oil, the oil can disperse over a radius of 50 m, forming a slick 10-mm thick. The slick gets thinner (less than 1 mm) as oil continues to spread, covering an area of up to 12 km2. During the first several days after the spill, a considerable part of oil transforms into the gaseous phase. Besides volatile components, the slick rapidly loses water-soluble hydrocarbons. The more viscous fractions slow down the slick spreading.

Further changes take place under the combined impact of meteorological factors and depend mainly on the power and direction of wind, waves and currents. An oil slick usually drifts in the same direction as the wind. While the slick thins, especially after the critical thickness of about 0.1 mm, it disintegrates into separate fragments that spread over larger and more distant areas. Storms and active turbulence speed up the dispersion of the slick and its fragments. A considerable part of oil disperses in the water as fine droplets that can be transported over large distances.


Most oil components are water-soluble to a certain degree, especially the aromatic hydrocarbons. Compared with evaporation, dissolution takes more time. Hydrodynamic conditions in the surface waters strongly affect the rate of the process.


Oil emulsification in the marine environment depends on oil composition and the turbulent regime of the water mass. The most stable emulsions such as water-in-oil contain from 30% to 80% water. They usually appear after strong storms in the zones of spills of heavy oils with an increased content of nonvolatile fractions like asphaltenes. They can exist in the marine environment for over 100 days in the form of peculiar “chocolate mousses”. Stability of these emulsions usually increases with decreasing temperature. The reverse emulsions, such as droplets of oil suspended in water, are much less stable because surface-tension forces quickly decrease the dispersion of oil. This process can be slowed with the help of emulsifiers. Emulsifiers help to stabilize oil emulsions and promote dispersing oil to form microscopic (invisible) droplets. This accelerates the decomposition of oil products in the water column.

Oxidation and destruction

Chemical transformation of oil on the water surface and in the water column start to reveal no earlier than a day after the oil enters the marine environment. They mainly have an oxidative nature and often involve photochemical reactions under the influence of ultraviolet waves of the solar spectrum. The final products of oxidation usually have increased water solubility. This increases the oil’s viscosity and promotes the formation of solid oil aggregates.


Some of the oil (up to 10-30%) is adsorbed on the suspended material and deposited to the bottom. This mainly happens in the narrow coastal zone and shallow waters where particulates are abundant and water is subjected to intense mixing. In deeper areas remote from the shore, sedimentation of oil is an extremely slow process.

Simultaneously, the process of biosedimentation happens. Plankton filtrators and other organisms absorb the emulsified oil. They settle to the bottom as sediment.

Numerous experimental and field studies show that the decomposition rate of the oil buried on the bottom abruptly drops. The oxidation processes slow down, especially under anaerobic conditions in the bottom environment. The heavy oil fractions accumulated inside the sediments can be preserved for many months and even years.

Microbial degradation

The fate of most petroleum substances in the marine environment is ultimately defined by their transformation and degradation due to microbial activity. About a hundred known species of bacteria and fungi are able to use oil components to sustain their growth and metabolism.

Biochemical processes of oil degradation with microorganism participation include several types of enzyme reactions. These cause biochemical transformations of the original oil substances and the intermediate products of their degradation.

The degree and rates of hydrocarbon biodegradation depend, upon the structure of their molecules. The paraffin compounds (alkanes) biodegrade faster than aromatic and naphthenic substances. The most important environmental factors that influence hydrocarbon biodegradation include temperature, concentration of nutrients and oxygen, and, of course, species composition and abundance of oil-degrading microorganisms.


Oil aggregates in the form of petroleum lumps, tar balls can be presently found both in the open and coastal waters as well as on the beaches. They derive from crude oil after the evaporation and dissolution of its relatively light fractions, emulsification of oil residuals and chemical and microbial transformation. The chemical composition of oil aggregates is rather changeable.

Oil aggregates look like light gray, brown, dark brown, or black sticky lumps. They have an uneven shape and vary from 1 mm to 10 cm in size (sometimes reaching up to 50 cm). Their surface serves as a substrate for developing bacteria, unicellular algae, and other microorganisms.

Oil aggregates can exist from a month to a year in the enclosed seas and up to several years in the open ocean. They complete their cycle by slowly degrading in the water column, on the shore (if they are washed there by currents), or on the sea bottom (if they lose their floating ability).


As a result of the processes previously discussed, oil in the marine environment rapidly loses its original properties and disintegrates into hydrocarbon fractions. These fractions have different chemical composition and undergo radical transformations that slow after reaching equilibrium with the environmental parameters. Their content gradually drops as a result of dispersion and degradation. Eventually, the original and intermediate compounds disappear, and carbon dioxide and water form. Such self-purification of the marine environment inevitably happens in water ecosystems if, of course, the toxicity does not exceed acceptable limits.

Note: Requirements for oil pollution emergency plans and relevant oil pollution reporting procedures are contained in Articles 3 and 4 of the 1990 OPRC Convention. This information is also provided to enable compliance with Regulation 17 of MARPOL Annex II which, inter alia, requires that the shipboard marine pollution emergency plans for oil and/or noxious liquid substances (SMPEP) shall contain a list of authorities or persons to be contacted in the event of a pollution incident involving such substances

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