2.1.1 Table 1 lists the engine performance parameters that should be measured, or calculated, and recorded at each mode point during on-board NOx monitoring.

　

　

2.1.2 Other engine settings necessary to define engine-operating conditions, e.g. wastegate, charge air bypass, turbocharger status, should be determined and recorded.

　

2.1.3 The settings and operating conditions of NOx control devices should be determined and recorded.

　

2.1.4 The engine power and speed should be measured to determine whether the engine is operated in a mode according to the specified test cycles (cf. section 3.1 of these Guidelines).

　

2.1.5 If it is difficult to measure power directly, uncorrected brake power may be estimated by any other means as approved by the Administration (cf. NOx Technical Code, paragraphs 6.3.1.3, 6.3.3.2 and 6.3.7). Possible methods to determine brake power include, but are not limited to:

　

　

2.1.6 The fuel flow (actual consumption rate) should be determined by:

　

　

　

2.2.1 Table 2 lists the ambient condition parameters that should be measured, or calculated, and recorded at each mode point during on-board NOx monitoring.

　

　

　

 The engine performance and ambient condition monitoring equipment should be installed and maintained in accordance with manufacturers' recommendations such that requirements of the NOx Technical Code, appendix 4, paragraph 1.3.2 and tables 3 and 4, are met in respect of the permissible deviations.

　

　

2.4.1 Electrical equipment should be constructed of durable, flame-retardant, moisture resistant materials, which are not subject to deterioration in the installed environment and at the temperatures to which the equipment is likely to be exposed.

　

2.4.2 Electrical equipment should be designed such that current carrying parts with potential to earth are protected against accidental contact.

　

　

　

3.1.1 Engine operation on board under a specified test cycle may not always be possible, but the test procedure, as approved by the Administration, should be as close as possible to the procedure defined in the NOx Technical Code, paragraph 3.2.

　

3.1.2 Regarding the E3 test cycle, if the actual propeller curve differs from the E3 curve, the load point used should be set using the engine speed, or the corresponding mean effective pressure (MEP) or mean indicated pressure (MIP), given for the relevant mode of that cycle.

　

3.1.3 If the number of measuring points on-board is different from those on the test bed, the number of measurement points and the weighting factors should be approved by the Administration.

　

3.1.4 Regarding the E2/E3/D2 test cycles, a minimum of load points should be used of which the combined nominal weighing factor, as given in the NOx Technical Code, paragraph 3.2, is greater than 0.50.

　

3.1.5 Regarding the C1 test cycle, a minimum number of one load point should be used from each of the rated, intermediate and idle speed sections.

　

3.1.6 If the number of measuring points on board is different from those on the test bed, the nominal weighting factors at each load point should be increased proportionally in order to sum to unity (1.0).

　

3.1.7 An example of the selection of load points and revised weighting factors are given in appendix 2.

　

3.1.8 The actual load points used to demonstrate compliance should be within ±5% of the rated power at the modal point except in the case of 100% load where the range should be +0 to -10%. For example, at the 75% load point the acceptable range should be 70% - 80% of rated power.

　

3.1.9 At each selected load point, except idle, and after the initial transition period (if applicable), the engine power should be maintained at the load set point within a 5% coefficient of variance (%C.O.V.) over a 10-minute interval. A worked example of the coefficient of variance calculation is given in appendix 3.

　

3.1.10 Regarding the C1 test cycle, the idle speed tolerance should be declared, subject to the approval of the Administration.

　

　

 The test condition parameter specified in the NOx Technical Code, paragraph 5.2.1, should not apply to on-board NOx monitoring. Data under any prevailing ambient condition should be acceptable.

　

　

3.3.1 Analysing equipment should be operated in accordance with manufacturer's recommendations.

　

3.3.2 Prior to measurement, zero and span values should be checked and the analyser should be adjusted as necessary.

　

3.3.3 After measurement, analyser zero and span values should be verified as being within that permitted in the NOx Technical Code, paragraph 5.9.9.

　

　

3.4.1 The output of the analysers should be recorded both during the test and during all response checks (zero and span). This data should be recorded on a strip chart recorder or other types of data recording devices.

　

3.4.2 For the evaluation of the gaseous emissions, a 1-Hertz minimum chart reading of a stable 10-minute sampling interval of each load point should be averaged. The average concentrations (conc) of NOx, O2 and/or CO2, if required, and optionally CO and HC, should be determined from the averaged chart readings and the corresponding calibration data.

　

3.4.3 As a minimum, emission concentrations, engine performance and ambient condition data should be recorded over the aforementioned 10-minute period.

　

　

　

 Fuel composition, to calculate gas mass flow wet (GEXHW), should be provided by one of the following:

　

　

　

 Exhaust gas density, to calculate gas mass flow wet (GEXHW) and NOx Technical Code Table 5, coefficient 'u', should be provided by one of the following:

　

　

　

 If not already measured on a wet basis, the gaseous emissions concentrations as per paragraph 2 of these Guidelines should be converted to a wet basis according to:

　

　

　

 NOx corrections for humidity and temperature should be performed as per NOx Technical Code, paragraph 5.12.3. The reference charge, or scavenge, air temperature (Tcs ref) should be stated and approved by the Administration. The Tsc ref values are to be referenced to 25℃ sea water temperature and in the application of the Tsc ref value due allowance should be made for the actual sea water temperature.

　

　

Exhaust gas flow rate should be determined by:

　

　

　

 The calculation of emission flow rates and specific emissions should be performed as per NOx Technical Code, paragraphs 5.12.4 and 5.12.5.

　

　

　

 The emission value obtained by the direct monitoring and measurement method should be compared to the NOx emission limit value as given in regulation 13 of Annex VI, plus allowance values as given in the NOx Technical Code, paragraphs 6.3.11.1, 6.3.11.2 and 6.3.11.3 in order to verify that an engine continues to comply with the requirements of regulation 13 of Annex VI.

　

　

 Compliance is required to be demonstrated at annual/intermediate, periodic and unscheduled surveys or following a substantial modification as per the NOx Technical Code, paragraph 1.3.2. In accordance with the NOx Technical Code, paragraph 2.3.4, data is required to be current; that is within 30 days. Data is required to be retained on board for at least three months. These time periods should be taken to be when the ship is in operation. Data within that 30-day period either may be collected as a single test sequence across the required load points or may be obtained on two or more separate occasions when the engine load corresponds to that required under section 3.1 of these Guidelines.

　

　

 The direct measurement and monitoring method should be documented in an on-board monitoring manual based on these Guidelines. The manual should be submitted to the Administration for approval. The approval reference of that manual should be entered under section 3 of the Supplement to the EIAPP Certificate. The Administration may issue a new EIAPP Certificate, with the details in section 3 of the Supplement duly amended, if the method is approved after the issue of the first EIAPP Certificate, i.e. following the pre-certification survey.

　

　

 The survey of the direct measurement and monitoring method should take into account, but is not limited to: