2.5 Steps to control discharge
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Statutory Documents - IMO Publications and Documents - Guidelines - SOPEP - Guidelines for the Development of Shipboard Oil Pollution Emergency PlansResolution MEPC.54(32) Amended by Resolution MEPC.86(44) - 2 Mandatory Provisions of Regulation 26 Of Annex I to the Convention - 2.5 Steps to control discharge

2.5 Steps to control discharge

  2.5.1 Ship personnel will almost always be in the best position to take quick action to mitigate 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.

  2.5.2 The Plan should outline the procedures for safe removal of oil spilled and contained on deck. Differences in ship type, construction, cargo, equipment, manning, and even route may result in a change in emphasis on various aspects of this section. As a minimum, the Plan should provide the master with guidance to address the following:

  • .1 Operational spills: The Plan should outline the procedures for safe 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.

    • .1.1 Pipe leakage: The Plan should provide specific guidance for dealing with pipe leakage.

    • .1.2 Tank overflow: Procedures for dealing with tank overflows should be 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.

    • .1.3 Hull leakage: The Plan should provide 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.

  • .2 Spills resulting from casualties: Casualties should be treated in the Plan as a separate section. The Plan should include various checklists or other means which will ensure that the master considers all appropriate factors when addressing the specific casualtyfootnote. These checklists must be tailored to the specific ship and to the specific product or product types. In addition to the checklists, specific personnel assignments for anticipated tasks must be identified. Reference to existing fire control plans and muster lists is sufficient to identify personnel responsibilities. The following are examples of casualties which should be considered:

    • .2.1 grounding;

    • .2.2 fire/explosion;

    • .2.3 collision;

    • .2.4 hull failure;

    • .2.5 excessive list.

    • .2.6 containment system failure;

    • .2.7 submerged/foundered;

    • .2.8 wrecked/stranded;

    • .2.9 hazardous vapour release.

  2.5.3 In addition to the checklists and personnel duty assignments mentioned in 2.5.2, the Plan should provide the master with guidance concerning priority actions, stability and stress considerations, lightening and mitigating activities.

  2.5.3.1 Priority actions: This section provides some general considerations that apply to a wide range of casualties. The Plan should provide ship-specific guidance to the master concerning these broad topics.

  • .1 In responding to a casualty, the master's priority will be to ensure the safety of personnel and the ship and to take action to prevent escalation of the incident. In casualties involving spills, immediate consideration should be given to measures aimed at preventing fire, personnel exposure to toxic vapours, and explosion, such as altering course so that the ship is upwind of the spilled cargo, shutting down non-essential air intakes, etc. If the ship is aground, and cannot therefore manoeuvre, all possible sources of ignition should be eliminated and action should be taken to prevent toxic vapours or flammable vapours entering accommodation and engine-room spaces (see paragraph 1.4.7). When it is possible to manoeuvre, the master, in conjunction with the appropriate shore authorities, may consider moving the ship to a more suitable location in order, for example, to facilitate emergency repair work or lightening operations, or to reduce the threat posed to any particularly sensitive shoreline areas. Such manoeuvring may be subject to coastal State jurisdiction.

  • .2 Prior to considering remedial action, the master will need to obtain detailed information on the damage sustained by the ship. A visual inspection should be carried out and all cargo tanks, bunker tanks, and other compartments should be sounded. Due regard should be paid to the indiscriminate opening of ullage plugs or sighting ports, especially when the ship is aground, as loss of buoyancy could result.

  • .3 Having assessed the damage sustained by the ship, the master will be in a position to decide what action should be taken to prevent or minimize further spillage. When bottom damage is sustained, hydrostatic balance will be achieved fairly rapidly, especially if the damage is severe, in which case the time available for preventive action will often be limited. When significant side damage is sustained in the way of oil tanks, cargo or bunkers will be released fairly rapidly until hydrostatic balance is achieved and the rate of release will then reduce and be governed by the rate at which oil is displaced by water flowing in under the oil. When the damage is fairly limited and restricted, for example, to one or two compartments, consideration may be given to transferring oil internally from damaged to intact tanks.

  2.5.3.2 Stability and strength considerations: Great care in casualty response must be taken to consider stability and strength 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. Nothing in this section shall be construed as creating a requirement for damage stability plans or calculations beyond those required by relevant international conventions.

  • .1 Internal transfers should be undertaken only with a full appreciation of the likely impact on the ship's overall longitudinal strength and stability. When the damage sustained is extensive, the impact of internal transfers on stress and stability may be impossible for the ship to assess. Contact may have to be made with the owner or operator or other entity in order that information can be provided so that damage stability and damage longitudinal strength assessments may be made. These could be made within the head office technical departments. In other cases, classification societies or independent organizations may need to be contacted. The Plan should clearly indicate who the master should contact in order to gain access to these facilities.

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

  2.5.3.3 Lightening: 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. Reference may be made in the Plan to existing company guides. 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 (see paragraph 1.4.7).

  2.5.3.4 Mitigating activities: When the safety of both the ship and personnel has been addressed, the master can initiate mitigating activities according to the guidance given by the plan. The plan should address such aspects as:

  • .1 assessment and monitoring requirements;

  • .2 personnel protection issues:

    • .2.1 protective equipment; and

    • .2.2 threats to health and safety

  • .3 containment and other response techniques (e.g. dispersing, absorbing,);

  • .4 isolation procedures;

  • .5 decontamination of personnel; and

  • .6 disposal of removed oil and clean-up materials."

  2.5.4 In order to have the necessary information available to respond to the situations referred to in 2.5.2, 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, is available.

Parent topic: 2 Mandatory Provisions of Regulation 26 Of Annex I to the Convention
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