Annex VI- Regulations for the Prevention of Air Pollution from Ships

Chapter 3 - Requirements for control of emissions from ships

Regulation 13 - Nitrogen oxides (NOx)
(1) (a) This regulation shall apply to:
    (i) each diesel engine with a power output of more than 130 kW which is installed on a ship constructed on or after 1 January 2000; and
    (ii) each diesel engine with a power output of more than 130 kW which undergoes a major conversion on or after 1 January 2000.
  (b) This regulation does not apply to:
    (i) emergency diesel engines, engines installed in lifeboats and any device or equipment intended to be used solely in case of emergency; and

SEE INTERPRETATION 13.1
  (ii) engines installed on ships solely engaged in voyages within waters subject to the sovereignty or jurisdiction of the State the flag of which the ship is entitled to fly, provided that such engines are subject to an alternative NOx control measure established by the Administration.
  (c) Notwithstanding the provisions of sub-paragraph (a) of this paragraph, the Administration may allow exclusion from the application of this regulation to any diesel engine which is installed on a ship constructed, or on a ship which undergoes a major conversion, before the date of entry into force of the present Protocol, provided that the ship is solely engaged in voyages to ports or offshore terminals within the State the flag of which the ship is entitled to fly.

SEE INTERPRETATION 13.2
(2) (a) For the purpose of this regulation, major conversion means a modification of an engine where:
    (i) the engine is replaced by a new engine built on or after 1 January 2000, or
    (ii) any substantial modification, as defined in the NOx Technical Code, is made to the engine, or
    (iii) the maximum continuous rating of the engine is increased by more than 10%.

SEE INTERPRETATION 13.3
  (b) The NOx emission resulting from modifications referred to in the sub-paragraph (a) of this paragraph shall be documented in accordance with the NOx Technical Code for approval by the Administration.
 
(3) (a) Subject to the provision of regulation 3 of this Annex, the operation of each diesel engine to which this regulation applies is prohibited, except when the emission of nitrogen oxides (calculated as the total weighted emission of NO2) from the engine is within the following limits:
    (i) 17.0 g/kW·h when n is less than 130 rpm
    (ii) 45.0 x n-0.2 g/kW·h when n is 130 or more but less than 2000 rpm
    (iii) 9.8 g/kW·h when n is 2000 rpm or more
    where n = rated engine speed (crankshaft revolutions per minute).
    When using fuel composed of blends from hydrocarbons derived from petroleum refining, test procedure and measurement methods shall be in accordance with the NOx Technical Code, taking into consideration the test cycles and weighting factors outlined in appendix II to this Annex.
  (b) Notwithstanding the provisions of sub-paragraph (a) of this paragraph, the operation of a diesel engine is permitted when:
    (i) an exhaust gas cleaning system, approved by the Administration in accordance with the NOx Technical Code, is applied to the engine to reduce onboard NOx emissions at least to the limits specified in sub-paragraph (a), or
    (ii) any other equivalent method, approved by the Administration taking into account relevant guidelines to be developed by the Organization, is applied to reduce onboard NOx emissions at least to the limit specified in sub-paragraph (a) of this paragraph.