Regulation 1 - Definitions
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Regulation 1 - Definitions

 For the purposes of this Annex:

  1 Oil means petroleum in any form including crude oil, fuel oil, sludge, oil refuse and refined products (other than those petrochemicals which are subject to the provisions of Annex II of the present Convention) and, without limiting the generality of the foregoing, includes the substances listed in appendix I to this Annex.

  2 Crude oil means any liquid hydrocarbon mixture occurring naturally in the earth whether or not treated to render it suitable for transportation and includes:

  • .1 crude oil from which certain distillate fractions may have been removed; and

  • .2 crude oil to which certain distillate fractions may have been added.

  3 Oily mixture means a mixture with any oil content.

  4 Oil fuel means any oil used as fuel in connection with the propulsion and auxiliary machinery of the ship in which such oil is carried.

  5 Oil tanker means a ship constructed or adapted primarily to carry oil in bulk in its cargo spaces and includes combination carriers, any "NLS tanker" as defined in Annex II of the present Convention and any gas carrier as defined in regulation 3.20 of chapter II-1 of SOLAS 74 (as amended), when carrying a cargo or part cargo of oil in bulk.

  6 Crude oil tanker means an oil tanker engaged in the trade of carrying crude oil.

  7 Product carrier means an oil tanker engaged in the trade of carrying oil other than crude oil.

  8 Combination carrier means a ship designed to carry either oil or solid cargoes in bulk.

  9 Major conversion:

  • .1 means a conversion of a ship:

    • .1.1 which substantially alters the dimensions or carrying capacity of the ship; or

    • .1.2 which changes the type of the ship; or

    • .1.3 the intent of which in the opinion of the Administration is substantially to prolong its life; or

    • .1.4 which otherwise so alters the ship that, if it were a new ship, it would become subject to relevant provisions of the present Convention not applicable to it as an existing ship.

  • .2 Notwithstanding the provisions of this definition:

    • .2.1 conversion of an oil tanker of 20,000 tonnes deadweight and above delivered on or before 1 June 1982, as defined in regulation 1.28.3, to meet the requirements of regulation 18 of this Annex shall not be deemed to constitute a major conversion for the purpose of this Annex; and

    • .2.2 conversion of an oil tanker delivered before 6 July 1996, as defined in regulation 1.28.5, to meet the requirements of regulation 19 or 20 of this Annex shall not be deemed to constitute a major conversion for the purpose of this Annex.

  10 Nearest land. The term “from the nearest land” means from the baseline from which the territorial sea of the territory in question is established in accordance with international law, except that, for the purposes of the present Convention "from the nearest land" off the north-eastern coast of Australia shall mean from a line drawn from a point on the coast of Australia in:

  latitude 11°00' S, longitude 142°08' E
  to a point in latitude 10°35' S, longitude 141°55' E,
  thence to a point latitude 10°00' S, longitude 142°00' E,
  thence to a point latitude 09°10' S, longitude 143°52' E,
  thence to a point latitude 09°00' S, longitude 144°30' E,
  thence to a point latitude 10°41' S, longitude 145°00' E,
  thence to a point latitude 13°00' S, longitude 145°00' E,
  thence to a point latitude 15°00' S, longitude 146°00' E,
  thence to a point latitude 17°30' S, longitude 147°00' E,
  thence to a point latitude 21°00' S, longitude 152°55' E,
  thence to a point latitude 24°30' S, longitude 154°00' E,
  thence to a point on the coast of Australia
  in latitude 24°42' S, longitude 153°15' E.

  11 Special area means a sea area where for recognized technical reasons in relation to its oceanographical and ecological condition and to the particular character of its traffic the adoption of special mandatory methods for the prevention of sea pollution by oil is required.

For the purposes of this Annex, the special areas are defined as follows:

  • .1 the Mediterranean Sea area means the Mediterranean Sea proper including the gulfs and seas therein with the boundary between the Mediterranean and the Black Sea constituted by the 41° N parallel and bounded to the west by the Straits of Gibraltar at the meridian of 005°36' W;

  • .2 the Baltic Sea area means the Baltic Sea proper with the Gulf of Bothnia, the Gulf of Finland and the entrance to the Baltic Sea bounded by the parallel of the Skaw in the Skagerrak at 57°44.8' N;

  • .3 the Black Sea area means the Black Sea proper with the boundary between the Mediterranean Sea and the Black Sea constituted by the parallel 41° N;

  • .4 the Red Sea area means the Red Sea proper including the Gulfs of Suez and Aqaba bounded at the south by the rhumb line between Ras si Ane (12°28.5' N, 043°19.6' E) and Husn Murad (12°40.4' N, 043°30.2' E);

  • .5 the Gulfs area means the sea area located north-west of the rhumb line between Ras al Hadd (22°30' N, 059°48' E) and Ras al Fasteh (25°04' N, 061° 25' E);

  • .6 the Gulf of Aden area means that part of the Gulf of Aden between the Red Sea and the Arabian Sea bounded to the west by the rhumb line between Ras si Ane (12°28'.5 N, 043°19'.6 E) and Husn Murad (12°40'.4 N, 043°30'.2 E) and to the east by the rhumb line between Ras Asir (11°50' N, 051°16'.9 E) and the Ras Fartak (15°35' N, 052°13'.8 E);

  • .7 the Antarctic area means the sea area south of latitude 60°S; and

  • .8 the North West European waters include the North Sea and its approaches, the Irish Sea and its approaches, the Celtic Sea, the English Channel and its approaches and part of the North East Atlantic immediately to the west of Ireland. The area is bounded by lines joining the following points:

      48° 27' N on the French coast
      48° 27' N; 006° 25' W
      49° 52' N; 007° 44' W
      50° 30' N; 012° W
      56° 30' N; 012° W
      62° N; 003° W
      62° N on the Norwegian coast
      57° 44.8' N on the Danish and Swedish coasts
  • .9 the Oman area of the Arabian Sea means the sea area enclosed by the following coordinates:

      22° 30'.00 N; 059° 48'.00 E
      23° 47'.27 N; 060° 35'.73 E
      22° 40'.62 N; 062° 25'.29 E
      21° 47'.40 N; 063° 22'.22 E
      20° 30'.37 N; 062° 52'.41 E
      19° 45'.90 N; 062° 25'.97 E
      18° 49'.92 N; 062° 02'.94 E
      17° 44'.36 N; 061° 05'.53 E
      16° 43'.71 N; 060° 25'.62 E
      16° 03'.90 N; 059° 32'.24 E
      15° 15'.20 N; 058° 58'.52 E
      14° 36'.93 N; 058° 10'.23 E
      14° 18'.93 N; 057° 27'.03 E
      14° 11'.53 N; 056° 53'.75 E
      13° 53'.80 N; 056° 19'.24 E
      13° 45'.86 N; 055° 54'.53 E
      14° 27'.38 N; 054° 51'.42 E
      14° 40'.10 N; 054° 27'.35 E
      14° 46'.21 N; 054° 08'.56 E
      15° 20'.74 N; 053° 38'.33 E
      15° 48'.69 N; 053° 32'.07 E
      16° 23'.02 N; 053° 14'.82 E
      16° 39'.06 N; 053° 06'.52 E
  • .10 the Southern South African waters means the sea area enclosed by the following co-ordinates:

      31° 14΄ S; 017° 50΄ E
      31° 30΄ S; 017° 12΄ E
      32° 00΄ S; 017° 06΄ E
      32° 32΄ S; 016° 52΄ E
      34° 06΄ S; 017° 24΄ E
      36° 58΄ S; 020° 54΄ E
      36° 00΄ S; 022° 30΄ E
      35° 14΄ S; 022° 54΄ E
      34° 30΄ S; 026° 00΄ E
      33° 48΄ S; 027° 25΄ E
      33° 27΄ S; 027°12΄ E

  12 Instantaneous rate of discharge of oil content means the rate of discharge of oil in litres per hour at any instant divided by the speed of the ship in knots at the same instant.

  13 Tank means an enclosed space which is formed by the permanent structure of a ship and which is designed for the carriage of liquid in bulk.

  14 Wing tank means any tank adjacent to the side shell plating.

  15 Centre tank means any tank inboard of a longitudinal bulkhead.

  16 Slop tank means a tank specifically designated for the collection of tank drainings, tank washings and other oily mixtures.

  17 Clean ballast means the ballast in a tank which since oil was last carried therein, has been so cleaned that effluent therefrom if it were discharged from a ship which is stationary into clean calm water on a clear day would not produce visible traces of oil on the surface of the water or on adjoining shorelines or cause a sludge or emulsion to be deposited beneath the surface of the water or upon adjoining shorelines. If the ballast is discharged through an oil discharge monitoring and control system approved by the Administration, evidence based on such a system to the effect that the oil content of the effluent did not exceed 15 parts per million shall be determinative that the ballast was clean, notwithstanding the presence of visible traces.

  18 Segregated ballast means the ballast water introduced into a tank which is completely separated from the cargo oil and oil fuel system and which is permanently allocated to the carriage of ballast or to the carriage of ballast or cargoes other than oil or noxious liquid substances as variously defined in the Annexes of the present Convention.

  19 Length (L) means 96 per cent of the total length on a waterline at 85 per cent of the least moulded depth measured from the top of the keel, or the length from the foreside of the stem to the axis of the rudder stock on that waterline, if that be greater. In ships designed with a rake of keel the waterline on which this length is measured shall be parallel to the designed waterline. The length (L) shall be measured in metres.

  20 Forward and after perpendiculars shall be taken at the forward and after ends of the length (L). The forward perpendicular shall coincide with the foreside of the stem on the waterline on which the length is measured.

  21 Amidships is at the middle of the length (L).

  22 Breadth (B) means the maximum breadth of the ship, measured amidships to the moulded line of the frame in a ship with a metal shell and to the outer surface of the hull in a ship with a shell of any other material. The breadth (B) shall be measured in metres.

  23 Deadweight (DW) means the difference in tonnes between the displacement of a ship in water of a relative density of 1.025 at the load waterline corresponding to the assigned summer freeboard and the lightweight of the ship.

  24 Lightweight means the displacement of a ship in metric tons without cargo, fuel, lubricating oil, ballast water, fresh water and feed water in tanks, consumable stores, and passengers and crew and their effects.

  25 Permeability of a space means the ratio of the volume within that space which is assumed to be occupied by water to the total volume of that space.

  26 Volumes and areas in a ship shall be calculated in all cases to moulded lines.

  27 Anniversary date means the day and the month of each year, which will correspond to the date of expiry of the International Oil Pollution Prevention Certificate.

  28.1 Ship delivered on or before 31 December 1979 means a ship:

  • .1 for which the building contract is placed on or before 31 December 1975; or

  • .2 in the absence of a building contract, the keel of which is laid or which is at a similar stage of construction on or before 30 June 1976; or

  • .3 the delivery of which is on or before 31 December 1979; or

  • .4 which has undergone a major conversion:

    • .1 for which the contract is placed on or before 31 December 1975; or

    • .2 in the absence of a contract, the construction work of which is begun on or before 30 June 1976; or

    • .3 which is completed on or before 31 December 1979.

  28.2 Ship delivered after 31 December 1979 means a ship:

  • .1 for which the building contract is placed after 31 December 1975; or

  • .2 in the absence of a building contract, the keel of which is laid or which is at a similar stage of construction after 30 June 1976; or

  • .3 the delivery of which is after 31 December 1979; or

  • .4 which has undergone a major conversion:

    • .1 for which the contract is placed after 31 December 1975; or

    • .2 in the absence of a contract, the construction work of which is begun after 30 June 1976; or

    • .3 which is completed after 31 December 1979.

  28.3 Oil tanker delivered on or before 1 June 1982 means an oil tanker:

  • .1 for which the building contract is placed on or before 1 June 1979; or

  • .2 in the absence of a building contract, the keel of which is laid or which is at a similar stage of construction on or before 1 January 1980; or

  • .3 the delivery of which is on or before 1 June 1982; or

  • .4 which has undergone a major conversion:

    • .1 for which the contract is placed on or before 1 June 1979; or

    • .2 in the absence of a contract, the construction work of which is begun on or before 1 January 1980; or

    • .3 which is completed on or before 1 June 1982

  28.4 Oil tanker delivered after 1 June 1982 means an oil tanker:

  • .1 for which the building contract is placed after 1 June 1979; or

  • .2 in the absence of a building contract, the keel of which is laid or which is at a similar stage of construction after 1 January 1980; or

  • .3 the delivery of which is after 1 June 1982; or

  • .4 which has undergone a major conversion:

    • .1 for which the contract is placed after 1 June 1979; or

    • .2 in the absence of a contract, the construction work of which is begun after 1 January 1980; or

    • .3 which is completed after 1 June 1982.

  28.5 Oil tanker delivered before 6 July 1996 means an oil tanker:

  • .1 for which the building contract is placed before 6 July 1993; or

  • .2 in the absence of a building contract, the keel of which is laid or which is at a similar stage of construction before 6 January 1994; or

  • .3 the delivery of which is before 6 July 1996; or

  • .4 which has undergone a major conversion:

    • .1 for which the contract is placed before 6 July 1993; or

    • .2 in the absence of a contract, the construction work of which is begun before 6 January 1994; or

    • .3 which is completed before 6 July 1996.

  28.6 Oil tanker delivered on or after 6 July 1996 means an oil tanker:

  • .1 for which the building contract is placed on or after 6 July 1993; or

  • .2 in the absence of a building contract, the keel of which is laid or which is at a similar stage of construction on or after 6 January 1994; or

  • .3 the delivery of which is on or after 6 July 1996; or

  • .4 which has undergone a major conversion:

    • .1 for which the contract is placed on or after 6 July 1993; or

    • .2 in the absence of a contract, the construction work of which is begun on or after 6 January 1994; or

    • .3 which is completed on or after 6 July 1996.

  28.7 Oil tanker delivered on or after 1 February 2002 means an oil tanker:

  • .1 for which the building contract is placed on or after 1 February 1999; or

  • .2 in the absence of a building contract, the keel of which is laid or which is at a similar stage of construction on or after 1 August 1999; or

  • .3 the delivery of which is on or after 1 February 2002; or

  • .4 which has undergone a major conversion:

    • .1 for which the contract is placed on or after 1 February 1999; or

    • .2 in the absence of a contract, the construction work of which is begun on or after 1 August 1999; or

    • .3 which is completed on or after 1 February 2002.

  28.8 Oil tanker delivered on or after 1 January 2010 means an oil tanker:

  • .1 for which the building contract is placed on or after 1 January 2007; or

  • .2 in the absence of a building contract, the keel of which is laid or which is at a similar stage of construction on or after 1 July 2007; or

  • .3 the delivery of which is on or after 1 January 2010; or

  • .4 which has undergone a major conversion:

    • .1 for which the contract is placed on or after 1 January 2007; or

    • .2 in the absence of a contract, the construction work of which is begun on or after 1 July 2007; or

    • .3 which is completed on or after 1 January 2010.

  28.9 ship delivered on or after 1 August 2010 means a ship:

  • .1 for which the building contract is placed on or after 1 August 2007; or

  • .2 in the absence of a building contract, the keels of which are laid or which are at a similar stage of construction on or after 1 February 2008; or

  • .3 the delivery of which is on or after 1 August 2010; or

  • .4 which have undergone a major conversion:

    • .1 for which the contract is placed after 1 August 2007; or

    • .2 in the absence of contract, the construction work of which is begun after 1 February 2008; or

    • .3 which is completed after 1 August 2010.

  29 Parts per million (ppm) means parts of oil per million parts of water by volume.

  30 Constructed means a ship the keel of which is laid or which is at a similar stage of construction.

  31 Oil residue (sludge) means the residual waste oil products generated during the normal operation of a ship such as those resulting from the purification of fuel or lubricating oil for main or auxiliary machinery, separated waste oil from oil filtering equipment, waste oil collected in drip trays, and waste hydraulic and lubricating oils.

  32 Oil residue (sludge) tank means a tank which holds oil residue (sludge) from which sludge may be disposed directly through the standard discharge connection or any other approved means of disposal.

  33 Oily bilge water means water which may be contaminated by oil resulting from things such as leakage or maintenance work in machinery spaces. Any liquid entering the bilge system including bilge wells, bilge piping, tank top or bilge holding tanks is considered oily bilge water.

  34 Oily bilge water holding tank means a tank collecting oily bilge water prior to its discharge, transfer or disposal.

 35 Audit means a systematic, independent and documented process for obtaining audit evidence and evaluating it objectively to determine the extent to which audit criteria are fulfilled.

  36 Audit Scheme means the IMO Member State Audit Scheme established by the Organization and taking into account the guidelines developed by the Organizationfootnote.

  37 Code for Implementation means the IMO Instruments Implementation Code (III Code) adopted by the Organization by resolution A.1070(28).

  38 Audit Standard means the Code for Implementation.

  39 Electronic Record Book means a device or system, approved by the Administration, used to electronically record the required entries for discharges, transfers and other operations as required under this Annex in lieu of a hard copy record book.

  40 Unmanned non-self-propelled (UNSP) barge means a barge that:

  • .1 is not propelled by mechanical means;

  • .2 carries no oil (as defined in regulation 1.1 of this Annex);

  • .3 has no machinery fitted that may use oil or generate oil residue (sludge);

  • .4 has no oil fuel tank, lubricating oil tank, oily bilge water holding tank and oil residue (sludge) tank; and

  • .5 has neither persons nor living animals on board.


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