As per the international convention for the prevention of pollution from ships, state the regulation and the annex to MARPOL 73/78 which requires oil tankers and other ships to carry a shipboard oil pollution emergency plan approved by the vessel flag administration. Discuss the mandatory requirement of SOPEP.

The requirement is in MARPOL 73/78 Annex I, Regulation 26 (Shipboard Oil Pollution Emergency Plan - SOPEP). It requires every oil tanker of 150 GT and above and every ship of 400 GT and above to carry on board a Shipboard Oil Pollution Emergency Plan approved by the Administration (the flag State). The SOPEP is also required under the OPRC Convention (1990) and is part of the ship's pollution-preparedness arrangements.

Mandatory requirements of the SOPEP:

• Approval: The SOPEP must be approved by the flag Administration (or a Recognised Organisation authorised by it). It is a ship-specific plan.
• Purpose: To provide the master and crew with a clear, practical procedure to follow in the event of an oil pollution incident, so that the spill is contained, reported and responded to promptly, minimising pollution.
• Contents (per the IMO guidelines for the SOPEP):

1. Reporting procedures: the procedure for reporting an oil pollution incident to the coastal State and the flag State, including the required information (the "reporting format" - the ship's name, position, the nature and quantity of the oil, the circumstances, and the contact points). The master must report any actual or probable discharge of oil.
2. Action to control the discharge: the steps to be taken to prevent or minimise the discharge (e.g. stopping the leak, transferring oil, closing valves, using the ship's response equipment, containment and recovery).
3. National and local coordination: the contact points of the coastal State, the flag State, the company, and the relevant authorities, and the procedure for coordinating the response with them.
4. The ship's response equipment: the inventory of the oil-spill response equipment carried on board (e.g. booms, absorbents, dispersants if carried) and how to use it.
5. The ship's particulars and the plan's distribution.

• The SOPEP is to be kept on board, available to the crew, and the crew are to be trained in its use; it is checked at surveys and by port State control.
• For ships carrying noxious liquid substances (Annex II), a Shipboard Marine Pollution Emergency Plan (SMPEP) covering both oil and NLS is required.
• The SOPEP is part of the ship's compliance with MARPOL and OPRC; failure to carry an approved SOPEP is a deficiency that can lead to detention.

The SOPEP ensures that the ship is prepared to respond to an oil spill, that the incident is reported promptly to the authorities, and that the response is coordinated, thereby reducing the environmental impact of an oil discharge.