The Shipboard Oil Pollution Emergency Plan, or SOPEP, is a prevention plan carried on board tankers >150 GT and other vessels >400 GT. It is a set of guidelines provided under Marpol to prevent oil pollution at sea. The plan is required by the International Maritime Organization under the Marine Environmental Protection Committee act. The gross tonnage requirement for an oil tanker, according to SOPEP, reduces to 150 GT as oil itself is a kind of cargo which doubles the risk of oil pollution.

SOPEP includes the following information:

• Drawing of various fuel lines, along with other oil lines on board vessel with the positioning of vents, save all trays etc.
• The general arrangement of the ship, which includes the location of all the oil tanks with capacity, content, etc.
• The location of the SOPEP locker and contents of the locker with a list of inventory
• Guidance to keep the records of the pollution incident (for liability, compensation, and insurance purpose)

SOPEP does not only provide details for preventing and fighting an oil spill, but it also acts similar to any other regulation of SOLAS as it also has the details to save the ship and crew in the event of an emergency.