UN R96 — Supplement 3 to the 05 series of amendments

Paragraph 3.1.1. now applies to engines operated on hydrogen and includes dual-fuel engines of Type 1A with hydrogen as a main fuel. Requirements for all other types of dual-fuel hydrogen engines have not yet been established under this Regulation. Paragraphs 5.6.4. and 8.7.2.3. and Annex 4, paragraph 5.1.2. now refer these dual-fuel engines to Annex 12. To receive a type-approval of such an engine, the manufacturer must comply with Annex 12 (Appendix 4, paras. A.4.2.7.1. and A.4.4.4.). Annex 7, Appendix A.2 does not apply if one of the fuels of a dual-fuel engine is hydrogen. The title of Annex 5 and its paragraph 1. now exclude all engines operated on hydrogen.

New Annex 12 defines additional requirements and exceptions for emission testing of dual-fuel engines of Type 1A with hydrogen as a main fuel. The requirements of Annex 7 and its Appendix A.1 for dual-fuel engines of Type 1A also apply to these engines. Gaseous constituents must be measured continuously from raw exhaust, and the dilution procedure of Annex 4, paragraph 9.2. does not apply to them. Emissions are calculated with Annex 5, Appendix A.1, with exceptions, and the molar-based calculations must not be used. Appendix A.2 gives new equations (A.12-1) to (A.12-5). Appendix A.3 shows the main requirements for dual-fuel engines operated on hydrogen and a liquid fuel.

Table 27, on the minimum number of tests for type-approval of dual-fuel engines, has a new H2 column with one fuel-specific test. Paragraph A.4.3.1. now refers to Tables 25 to 27, and paragraph A.4.2.5.1.2. now refers to paragraph A.4.2.3.1. In Annex 3, Appendix A.1, Table 3 adds suffix 10 for a dual-fuel engine approved for operation on hydrogen as gaseous component of fuel. Paragraph A.5.4.14. now refers to Annex 7, paragraphs 4.3.1 and 4.3.2 for the dual-fuel operating mode indicator and warning system.

New Appendix A.7 to Annex 4 gives the procedure for the measurement of water (H2O) with a QCL-IR or an FTIR analyser. It covers installation, cross interference, analyser drift, linearity, accuracy, response time and the H2O calibration gas. In Annex 11, paragraph 8.2., concentrations measured on a dry basis must now be converted to a wet basis by equation (A.11-1). Before, paragraph 8.2. said that Equation A.5-7 must not be used for engines operated solely on hydrogen. Under Annex 4, paragraph 9.3.2.3.1.1., sample dryers may not be used for a sample from which H2O or NH3 will be measured. A RegVault Note says that RegVault reads equation (A.12-1), printed without brackets, like equation (A.11-1); the Note is not part of the official text.

New paragraphs 2.1.102. and 2.1.103. define “Instrument manufacturer” and “Type of analyser”, and paragraph 2.2.2. adds FTIR and QCL-IR. From raw exhaust, CO, CO2 or NOx may be measured with an FTIR or QCL-IR analyser that meets paragraph 9.4.13. or 9.4.14., respectively. New paragraphs 9.4.13. and 9.4.14. give requirements for these analysers, including an analyser compliance declaration by the instrument manufacturer. New paragraphs 8.1.13. and 8.1.14. are headed “FTIR interference check” and “QCL-IR interference check”. Under new paragraph 9.4.15., the analyser manufacturer must check interference effects of the analysers of paragraphs 9.4.6. to 9.4.8., 9.4.13. and 9.4.14. before market introduction. In paragraph 9.4.10., the sentence that the sensor must be calibrated as specified by the instrument manufacturer is removed.

Equation (A.4-16) is amended, and equation (A.4-17) now adds TAUX to Tmap. One tolerance is now ±10 per cent of idle, instead of ≤ 10 per cent of idle. Paragraph references change, for example to paragraphs 8.1.8.5.7., 9.3.4.6., 8.2.3.8. and A.1.3.1.1. In Appendix A.1, the abbreviations PTT and POT are replaced by PTL and OT. Other wording corrections are in paragraphs 7.3.1.1., 7.7.2.2. and 9.2.2.

Under paragraph A.1.1.6. of Annex 5, Appendix A.1, the mass flow rate of the exhaust gas may be measured directly. The measuring system must meet the requirements of Annex 4, paragraph 9.4.5. Paragraph 1.3. of Annex 5 adds NH3 (ammonia) to the symbols for the chemical components. Two definitions of the fuel flow rate are reworded. Some symbols, equation numbers and references change.