3.1 Maximum allowable NOx emission limits for marine diesel engines
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Statutory Documents - IMO Publications and Documents - International Codes - NOx Technical Code (2008) - Technical Code on Control of Emission of Nitrogen Oxides from Marine Diesel Engines - Chapter 3 - Nitrogen oxides emission standards - 3.1 Maximum allowable NOx emission limits for marine diesel engines

3.1 Maximum allowable NOx emission limits for marine diesel engines

  3.1.1 The maximum allowable NOx emission limit values are given by paragraphs 3, 4, 5.1.1 and 7.4 of regulation 13 as applicable. The total weighted NOx emissions, as measured and calculated, rounded to one decimal place, in accordance with the procedures in this Code, shall be equal to or less than the applicable calculated value corresponding to the rated speed of the engine.

  3.1.2 When the engine operates on test fuel oils in accordance with 5.3, the total emission of nitrogen oxides (calculated as the total weighted emission of NO2) shall be determined using the relevant test cycles and measurement methods as specified in this Code.

  3.1.3 An engine’s exhaust emissions limit value, given from the formulae included in paragraph 3, 4 or 5.1.1 of regulation 13 as applicable, and the actual calculated exhaust emissions value, rounded to one decimal place for the engine, shall be stated on the engine’s EIAPP Certificate. If an engine is a member engine of an engine family or engine group, it is the relevant parent engine emission value that is compared to the applicable limit value for that engine family or engine group. The limit value given here shall be the limit value for the engine family or engine group based on the highest engine speed to be included in that engine family or engine group, in accordance with paragraph 3, 4 or 5.1.1 of regulation 13, irrespective of the rated speed of the parent engine or the rated speed of the particular engine as given on the engine’s EIAPP certificate.

  3.1.4 In the case of an engine to be certified in accordance with paragraph 5.1.1 of regulation 13 the specific emission at each individual mode point shall not exceed the applicable NOx emission limit value by more than 50% except as follows:

  • .1 The 10% mode point in the D2 test cycle specified in 3.2.5.

  • .2 The 10% mode point in the C1 test cycle specified in 3.2.6.

  • .3 The idle mode point in the C1 test cycle specified in 3.2.6.


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