Regulations on Oil Discharge Monitoring and Control System & Oil/water interface detector

Oil Discharge Monitoring and Control System (ODMCS) Requirements:

• This regulation comes under MARPOL Annex I, Chapter 4 - Requirements for the Cargo Area of Oil Tankers, Part B - Equipment, Regulation 31.

• All Oil tankers of 150 gross tonnages and above shall be equipped with an oil discharge monitoring and control system approved by the Administration.

• The design and specification of an Oil content meter incorporated in the system shall be approved by the Administration as recommended by the Organization.

• The ODMCS is designed and installed in compliance with the guidelines developed by the Organization.

• The system shall be fitted with a recording device to provide a continuous record of the discharge in litres per nautical miles and the total quantity discharged, or the oil content and rate of discharge.

• The records shall be identifiable as to time and date and shall be kept for at least three years.

• ODMCS shall come into operation when there is any discharge of effluent into the sea and shall be such as will ensure that any discharge of oily mixture is automatically stopped when the instantaneous rate of discharge of oil exceeds that permitted by regulation 34 of this Annex.

• Any failure of this monitoring and control system shall stop the effluent discharge.

• In the event of failure of ODMCS, a manually operated alternative method may be used, but the defective unit shall be made operable as soon as possible.

• Subject to the allowance of port state authority a tanker with defective ODMCS may undertake one ballast voyage before proceeding to the repair port.

• Instructions for the operations of the system shall be in accordance with an operational manual approved by the Administration.

• The Operation manual shall cover both automatic and Manual operations of the Oil Discharge Monitoring and Control System.

Oil/Water Interface Detector Requirements:

• This regulation comes under MARPOL Annex I, Chapter 4 - Requirements for the Cargo Area of Oil Tankers, Part B - Equipment, Regulation 32.

• Any Oil Tankers of 150 gross tonnages and above shall be provided with effective oil/water interface detectors approved by the Administration.

• Oil/water interface detectors available shall be rapid and accurate enough for the determination of the oil/water interface in slop tanks.

• It shall be available for use in other tanks where the separation of oil and water is effected and from which it is intended to discharge effluent direct to the sea. 

• Oil/water interface detectors shall be capable of detecting interfaces of liquids having a wide range of density differences.

• The instrument should be capable of being checked onboard for correct working.

• The approval document for the instrument should clearly state the accepted applications and any relevant limitations.

• It should comply with the relevant statutory requirements for the use in hazardous areas and should not interfere with radio communications.

Reference: 

IMO Publications & Documents - International Conventions - MARPOL - Annex I

IMO Publications & Documents - Resolution - Marine Environment Protection Committee - Resolution MEPC.5(XIII)