CoC Oral Exam Preparation (Part – 20): OWS & Regulations

MARPOL Regulations of Discharging Machinery Bilge into the sea:

The rules and Regulations that govern the operation of an Oily Water Separator are under MARPOL  Annex I: “Prevention of pollution by oil”.

Regulation 14: Oil Filtering Equipment

  1. Vessels above 400 GT and less than 1000 GT shall have an oil filtering equipment
  • Approved by the Administration
  • Will ensure that any oily mixture discharged into the sea after passing through the equipment has an oil content not exceeding 15 ppm

2.  Vessels above 1000 GT shall have an oil filtering equipment

    • In addition to the above, shall be provided with alarm arrangements to indicate when the level cannot be maintained.
    • Also arrangements to ensure that any discharge of oily mixture is automatically stopped when the oil content of the effluent exceeds 15 ppm

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A Short Note on Ship’s Energy Efficiency: EEDI, SEEMP & EEOI

The Energy Efficiency Design Index (EEDI) was made mandatory for new ships and the Ship Energy Efficiency Management Plan (SEEMP) for all ships at MEPC 62 (July 2011) with the adoption of amendments to MARPOL Annex VI (resolution MEPC.203(62)), by Parties to MARPOL Annex VI. This was the first legally binding climate change treaty to be adopted since the Kyoto Protocol. The new MARPOL Annex VI Chapter 4: Energy Efficiency requirements Enter into force on 1 January 2013.

Energy Efficiency Design Index (EEDI):

  • It is an index quantifying the amount of carbon dioxide that a ship emits in relation to the goods transported.
  • indication of energy efficiency by CO2 emission (g) per cargo carry (ton mile) The actual EEDI of a vessel is called the “attained EEDI” and is calculated based on guidelines published by IMO. The result must be below the limit “required EEDI” prescribed in MARPOL.
  • For existing vessels, the EEDI is in most cases irrelevant. It will become relevant only if a ship undergoes a major conversion that is so extensive that the ship is regarded by the Administration as a newly constructed ship.
  • For new ships, a technical file must be created showing the attained EEDI and its calculation process.
  • The EEDI and the technical file will be subject to verification by the flag administration.

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CoC Oral Exam Preparation (Part-7) – Maritime Security

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When do the security measures come into force ?

– 1st July, 2004.

SOLAS amendments adopted in December 2002 :

Chapter V:
– Automated Identifications Systems(AIS)

Chapter XI-1:
-Ship identification number
-Continuous Synopsis Record (CSR)

Chapter XI-2:
-Measures to enhance maritime security
-International Ship and Port Facility Security (ISPS) Code (Parts A & B)
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Diesel Engine Scavenge Fire


For any fire to begin, the fire tringle needs to be completed. To complete a fire tringle there must be present a combustible material, oxygen or air to support combustion and a source of heat at a temperature high enough to start combustion.

In the case of scavenge fires:
 the combustible material is oil. The oil can be cylinder oil which has drained down from the cylinder spaces, or crankcase oil carried upwards on the piston rod because of a faulty stuffing box. In some cases the cylinder oil residues may also contain fuel oil. The fuel may come from defective injectors, injectors with incorrect pressure setting, fuel particles striking the cylinders and other similar causes.
 The oxygen necessary for combustion comes from the scavenge air which is in plentiful supply for the operation of the engines.
 The source of heat for ignition comes from piston blow-by, slow ignition and afterburning, or excessive exhaust back pressure, which causes a blowback through the scavenge ports.
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Fuel Injector of Diesel Engines

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Older loop scavenged engines may have a single injector mounted centrally in the cylinder head. Because the exhaust valve is in the centre of the cylinder head on modern uniflow scavenged engines the fuel valves (2 or 3) are arranged around the periphery of the head.
The pressure at which the injector operates can be adjusted by adjusting the loading on the spring. The pressure at which the injectors operate vary depending on the engine, but can be as high as 540bar.


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 International Convention for the Prevention of Pollution from Ships,

1973, as modified by the Protocol of 1978.

The MARPOL Convention is the main international convention covering prevention of pollution of the marine environment by ships from operational or accidental causes. It is a combination of two treaties adopted in 1973 and 1978 respectively and updated by amendments through the years.

The International Convention for the Prevention of Pollution from Ships (MARPOL) was adopted on 2 November 1973 at IMO and covered pollution by oil, chemicals, harmful substances in packaged form, sewage and garbage. The Protocol of 1978 relating to the 1973 International Convention for the Prevention of Pollution from Ships (1978 MARPOL Protocol) was adopted at a Conference on Tanker Safety and Pollution Prevention in February 1978 held in response to a spate of tanker accidents in 1976-1977. (Measures relating to tanker design and operation were also incorporated into a Protocol of 1978 relating to the 1974 Convention on the Safety of Life at Sea, 1974).
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