The Conference of Parties
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Statutory Documents - IMO Publications and Documents - Circulars - Marine Environment Protection Committee - MEPC/Circular.369 - Amendments to Test Condition Parameter “fa” for Engine Family Approval in Accordance with the NOx Technical Code – (Adopted on 31 March 2000) - The Conference of Parties

The Conference of Parties

  1 The Conference of Parties to the International Convention for the Prevention of Pollution from Ships, 1973, as modified by the Protocol of 1978 relating thereto, held from 15 to 26 September 1997 in conjunction with the Marine Environment Protection Committee’s fortieth session, adopted, in Conference Resolution 2, the Technical Code on Control of Emission of Nitrogen Oxides from Marine Diesel Engines (The NOx Technical Code).

  2 The purpose of the NOx Technical Code is to establish mandatory procedures for the testing, survey and certification of marine diesel engines which will enable engine manufacturers, shipowners and Administrations to ensure that all applicable marine diesel engines comply with the relevant limits for emission values of NOx as specified in regulation 13 of Annex VI to MARPOL 73/78.

  3 It is noted that regulation 13 of MARPOL Annex VI is intended to be applied to diesel engines installed on ships constructed on or after 1 January 2000. While the requirements of the regulation could not be enforced before the entry into force of the Protocol of 1997, it should be clearly understood that engines installed on ships constructed on or after 1 January 2000 or engines which undergo a major conversion on or after 1 January 2000 will have to meet these requirements once the Protocol enters into force.

  4 It is also noted that it may not be possible, due to engine size, to provide test facilities where barometric pressure, temperature and humidity of the intake air can be controlled to maintain the “fa” factor within the range 0.98 = fa = 1.02. In consequence, the test for engine family approval may only be possible for a limited period during the year.

  5 It is further noted that the standard developed by the International Organization for Standardization, ISO 8178 Part 1, 1996, on which the NOx Technical Code was based, contains the following clause:

 “For a test to be recognized as valid, the parameter fa should be such that:

 0.98 = fa = 1.02

 If, for evident technical reasons, it is not possible to comply with this requirement, fa shall be between 0.93 and 1.07.”

  6 The Committee, at its forty-fourth session (6 to 8, 10 and 13 March 2000):

  • .1 approved the amendments to the Code, the text of which is set out in Annex; and

  • .2 agreed that upon entry into force of Annex VI of MARPOL 73/78, the necessary legal procedure for amending the Code should be initiated in accordance with Article 16 of the 1973 MARPOL Convention.

  7 To allow uniform application of the Code, and to assist Administrations in certifying engines in accordance with it, Governments are invited to accept the proposed amendments to the NOx Technical Code, attached at annex to this Circular, prior to their date of entry into force.


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