2.3 Procedures for certification of an engine
Clasification Society 2024 - Version 9.40
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 2 - Surveys and Certification - 2.3 Procedures for certification of an engine

2.3 Procedures for certification of an engine

  2.3.1 For those engines that have not been adjusted or modified relative to the original specification of the manufacturer, the provision of a valid EIAPP Certificate should suffice to demonstrate compliance with the applicable NOx limits.

  2.3.2 After installation on board, it shall be determined to what extent an engine has been subjected to further adjustments and/or modifications that could affect the NOx emission. Therefore, the engine, after installation on board, but prior to issuance of the IAPP Certificate, shall be inspected for modifications and be approved using the onboard NOx verification procedures and one of the methods described in 2.1.2.

  2.3.3 There are engines that, after pre-certification, need final adjustment or modification for performance. In such a case, the engine Group concept could be used to ensure that the engine still complies with the applicable limit.

  2.3.4 Every marine diesel engine installed on board a ship shall be provided with a technical file. The technical file shall be prepared by the applicant for engine certification and approved by the Administration, and is required to accompany an engine throughout its life on board ships. The technical file shall contain the information as specified in 2.4.1.

  2.3.5 Where a NOx reducing device is installed and needed to comply with the NOx limits, one of the options providing a ready means for verifying compliance with regulation 13 is the direct measurement and monitoring method in accordance with 6.4. However, depending on the technical possibilities of the device used, subject to the approval of the Administration, other relevant parameters could be monitored.

  2.3.6 Where, for the purpose of achieving NOx compliance, an additional substance is introduced, such as ammonia, urea, steam, water, fuel additives, etc., a means of monitoring the consumption of such substance shall be provided. The technical file shall provide sufficient information to allow a ready means of demonstrating that the consumption of such additional substances is consistent with achieving compliance with the applicable NOx limit.

  2.3.7 Where the engine parameter check method in accordance with 6.2 is used to verify compliance, if any adjustments or modifications are made to an engine after its pre-certification, a full record of such adjustments or modifications shall be recorded in the engine’s record book of engine parameters.

  2.3.8 If all of the engines installed on board are verified to remain within the parameters, components, and adjustable features recorded in the technical file, the engines should be accepted as performing within the applicable NOx limit specified in regulation 13. In this case, provided all other applicable requirements of the Annex are complied with, an IAPP Certificate should then be issued to the ship.

  2.3.9 If any adjustment or modification is made which is outside the approved limits documented in the technical file, the IAPP Certificate may be issued only if the overall NOx emission performance is verified to be within the required limits by: onboard simplified measurement in accordance with 6.3; or, reference to the test-bed testing for the relevant engine group approval showing that the adjustments or modifications do not exceed the applicable NOx emission limit. At surveys after the initial engine survey, the direct measurement and monitoring method in accordance with 6.4, as approved by the Administration, may alternatively be used.

  2.3.10 The Administration may, at its own discretion, abbreviate or reduce all parts of the survey on board, in accordance with this Code, to an engine that has been issued an EIAPP Certificate. However, the entire survey on board must be completed for at least one cylinder and/or one engine in an engine family or engine group, if applicable, and the abbreviation may be made only if all the other cylinders and/or engines are expected to perform in the same manner as the surveyed engine and/or cylinder. As an alternative to the examination of fitted components, the Administration may conduct that part of the survey on spare parts carried on board provided they are representative of the components fitted.

  2.3.11 Guidance in respect of the survey and certification of marine diesel engines at initial, renewal, annual and intermediate surveys, as described in chapter 2 of this Code, is given in the flowcharts in appendix 2 of this Code. Where discrepancies exist, the text of chapter 2 takes precedence.


Copyright 2022 Clasifications Register Group Limited, International Maritime Organization, International Labour Organization or Maritime and Coastguard Agency. All rights reserved. Clasifications Register Group Limited, its affiliates and subsidiaries and their respective officers, employees or agents are, individually and collectively, referred to in this clause as 'Clasifications Register'. Clasifications Register assumes no responsibility and shall not be liable to any person for any loss, damage or expense caused by reliance on the information or advice in this document or howsoever provided, unless that person has signed a contract with the relevant Clasifications Register entity for the provision of this information or advice and in that case any responsibility or liability is exclusively on the terms and conditions set out in that contract.