.2 Engine group concept
Engines are used primarily for main propulsion. They normally require adjustment or modification to suit the on-board operating conditions (NOx Technical Code paragraph 4.4.1), and the possibility for a reduction of approval testing for modifications to engines in production or in service is provided. (NOx Technical Code paragraph 4.4.2)
The case of proposal
6 As for engine family approval for large size engines, Japan has proposed to change the test validity range of parameter "fa" based on Japanese climates, and the amendment to 5.2.2 Test validity based on the following are adopted under the condition of "for evident technical reasons". (ISO 8178-1: 1996(E)5.2.2 Test validity)
.1 ISO 8178-1: 1996(E) shall specify to require the test bed measurement of not only NOx emission but also CO and HC emission and particulate emission (PT), and required range of test parameter "fa" is defined for all these emission components.
.2 The measurement of PT is affected due to test conditions, and the allowable limit of parameter "fa" is specified as 0.98≦fa≦1.02, and amended 0.93≦fa≦1.07 with PT correction change. (ISO 8178-1: 1996(E) 14.1.2)
.3 As for NOx, correction shall be specified to temperature and humidity conditions, but no correction change is required for parameter "fa" of 0.93≦fa≦1.07.
Evident technical reasons
7 The parent engine test period shall be decided depending on the temperature and humidity conditions conforming to the required range of the test parameter "fa". When the factory does not have the test facility to control temperature and humidity during tests at the required range of the test parameter "fa", and this facility is approved as an appropriate one corresponding to its production scale by the Administration, this shall be taken as the interpretation of "evident technical reasons" and investigated to apply increase of required range of the parameter "fa".
Proposal
8 Japan strongly expresses necessity of amendments to Regulation 5.2.1 of NOx Technical Code which is the same as ISO 8178-1: 1996(E). Japan also expresses the necessity to develop an interpretation on the words "evident technical reasons" because it should be uniformly dealt with in their amendments.
9 Japan is deeply concerned about this issue and proposes the following solution:
.1 The Committee agrees that paragraph 5.2.1 of the NOx Technical Code shall be the same as ISO8178-1:1996(E) after the entry into force (annex l).
.2 The Committee adopts MEPC resolution (annex 2).
Action requested of the Committee
10 The Committee is invited to note this proposal with attached annexes and refer it to a drafting group for detailed consideration.
