What are regulations regarding control of discharge of oil as per MARPOL ?

As per MARPOL 73/78, regulation 9

Discharge shall be prohibited when:

• The tanker is within a special area
• The tanker is less than 50 NM from the nearest land.
• The tanker is not proceeding en route.
• The instantaneous rate of discharge exceeds 30 liters per nautical mile.
• The total quantity discharged exceeds 1/15,000 of the total cargo the ship is carrying.
• The tanker does not have in operation an oil discharge monitoring and control system and a slop tank arrangement.

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Methods of prevention of pollution in Special Areas

The Special Areas are as follows: