Proposal to replace para. 9.3.2.8.1. and 9.3.2.9.1. to permit examination and verification of FTIR and QCL-IR analysers by type-approval authorities and designated technical services in addition to metrological institutes, preferably via witnessed testing at the instrument manufacturer’s premises, amend para. 9.3.9.2.2. to permit humidification techniques other than water bubblers and to clarify water concentration requirements for all fuels, and insert new Appendices 10 and 11 setting out a protocol for analyser assessment and a model certificate of acceptable analyser assessment.

Proposal to amend para. 9.3.2.1 in annex 4 to correct a paragraph number reference from ‘9.2.3.7.’ to ‘9.3.2.7.’ in the text describing measurement principles. The correction addresses a typographical error introduced in WP.29/2025/94.

Proposal to amend para. A.1.3.2.1. to modify the PEMS consistency check of exhaust mass flow and gas concentrations for fuels with a molar carbon to hydrogen ratio of 0. For such fuels, the formula in para. 8.4.1.6. of Annex 4 shall be used instead, with Equations 30 and 31 applied for Type 1A dual-fuel hydrogen engines. The verification shall not apply to engines operated on non-carbon fuels or dual-fuel engines when operated in dual-fuel mode with at least one fuel having a molar carbon to hydrogen ratio of 0.

Proposal to amend UN R49 to approve the use of hydrogen dual-fuel as a fuel in type approval of emissions for heavy-duty vehicles. The amendments introduce new requirements for measuring instruments such as FT-IR and QCL-IR, add symbols and specifications for hydrogen-fuelled engines specifying that only Type 1A hydrogen fuel is applicable, amend emission calculation formulas for ETC/ESC and WHDC test procedures, add new HO direct measurement methods for NOx wet correction calculation, and add declaration formats for FT-IR and QCL-IR approval.

Proposal to insert new definitions for ‘Instrument manufacturer’ and ‘Type of analyzer’, add symbols and abbreviations for hydrogen, water, ammonia, nitrogen dioxide, oxygen and particulates, add abbreviations for flame ionisation detector, Fourier transform infrared analyser, non-methane cutter and quantum cascade laser mid-infrared detection, amend provisions for hydrogen Type 1A dual fuel engines, modify fuel temperature requirements, insert procedures for water measurement using QCL-IR and FTIR analysers, add FTIR and QCL-IR analyser requirements and interference verification procedures, insert protocols and certificates for FTIR and QCL-IR analyser assessment, add fuel types including hydrogen, modify measurement procedures for dual-fuel hydrogen engines, and update related calculation methods and specifications throughout Annexes 4A, 4B and 11.

Proposal to amend para. 3.5.1. to include dual-fuel engines of Type 1A with hydrogen as gaseous fuel, amend para. 4.12.3.3.7. to establish a series of digits identifying dual-fuel engine types in the approval mark, insert new definitions for ‘Instrument manufacturer’ and ‘Type of analyzer’ in Annex 4 para. 3.1., insert new symbols and abbreviations in Annex 4 paras. 3.4. and 3.5., amend paras. 7.6.6., 7.7.4., and 8.1.1. to accommodate H₂O measurement and hydrogen engine calculations, amend para. 8.4.2.1., amend para. 8.6.2. to exclude CH₄ calculation when measured by FTIR or QCL-IR, amend para. 9.3.1.8. regarding gas drying, amend para. 9.3.2. to introduce FTIR and QCL-IR analyzers for CO, CO₂, CH₄, and NOx measurement with specifications in paras. 9.3.2.8. and 9.3.2.9., insert new para. 9.3.2.10. for independent analyzer assessment, amend para. 9.3.9. and para. 9.3.9.2.2. regarding interference effects and water quench checks, insert new paras. 9.3.9.5. and 9.3.9.6. for FTIR and QCL-IR interference checks, amend Annex 4 Appendix 2 para. A.2.1.2., amend Annex 4 Appendix 5 para. A.5.2., insert new Annex 4 Appendix 9 establishing procedure for H₂O measurement, insert new Annex 4 Appendix 10 for FTIR and QCL-IR analyzer assessment protocol, insert new Annex 4 Appendix 11 establishing model certificate for analyzer assessment, amend Annex 8 Appendix 1 paras. A.1.1., A.1.2.2., A.1.3.2.1., A.1.4.1., and A.1.4.3. for Type 1A hydrogen dual-fuel engines, amend Annex 15 paras. 4.2.2.3., 6.1., 10.3., and Appendix 4 paras. A.4.3.1., A.4.4.1.1., A.4.4.3.1., and A.4.4.3.3.

Proposal to replace para. 9.3.2.1., replace paras. 9.3.2.8.1. and 9.3.2.9.1., amend paras. 9.3.9.2.2. and 9.3.9.6., and insert new Appendices 10 and 11. The replacements clarify measurement principles, specify that analyser assessment may be conducted by type-approval authorities, designated technical services, or metrological institutes preferably via witnessed testing at the instrument manufacturer premises, and provide protocols and certificate models for analyser assessment. Amendments to para. 9.3.9.2.2. permit alternative humidification techniques and clarify that test gas shall be humidified to a water concentration approximately equal to the maximum water concentration expected during emission testing for all fuels. Amendment to para. 9.3.9.6. specifies that spectral resolution shall have a nominal value ≤0.5 cm⁻¹ to minimise cross interference.

Proposal to replace para. 9.3.2.8.1. and 9.3.2.9.1. to permit examination and verification of FTIR and QCL-IR analysers by type-approval authorities and designated technical services in addition to metrological institutes, preferably via witnessed testing at the instrument manufacturer’s premises, amend para. 9.3.9.2.2. to permit humidification techniques other than water bubblers and to clarify water concentration requirements for all fuels, and insert new Appendices 10 and 11 setting out a protocol for analyser assessment and a model certificate of acceptable analyser assessment.

Proposal to amend para. 9.3.2.1 in annex 4 to correct a paragraph number reference from ‘9.2.3.7.’ to ‘9.3.2.7.’ in the text describing measurement principles. The correction addresses a typographical error introduced in WP.29/2025/94.

Proposal to amend para. A.1.3.2.1. to modify the PEMS consistency check of exhaust mass flow and gas concentrations for fuels with a molar carbon to hydrogen ratio of 0. For such fuels, the formula in para. 8.4.1.6. of Annex 4 shall be used instead, with Equations 30 and 31 applied for Type 1A dual-fuel hydrogen engines. The verification shall not apply to engines operated on non-carbon fuels or dual-fuel engines when operated in dual-fuel mode with at least one fuel having a molar carbon to hydrogen ratio of 0.

Proposal to amend UN R49 to approve the use of hydrogen dual-fuel as a fuel in type approval of emissions for heavy-duty vehicles. The amendments introduce new requirements for measuring instruments such as FT-IR and QCL-IR, add symbols and specifications for hydrogen-fuelled engines specifying that only Type 1A hydrogen fuel is applicable, amend emission calculation formulas for ETC/ESC and WHDC test procedures, add new HO direct measurement methods for NOx wet correction calculation, and add declaration formats for FT-IR and QCL-IR approval.

Proposal to insert new definitions for ‘Instrument manufacturer’ and ‘Type of analyzer’, add symbols and abbreviations for hydrogen, water, ammonia, nitrogen dioxide, oxygen and particulates, add abbreviations for flame ionisation detector, Fourier transform infrared analyser, non-methane cutter and quantum cascade laser mid-infrared detection, amend provisions for hydrogen Type 1A dual fuel engines, modify fuel temperature requirements, insert procedures for water measurement using QCL-IR and FTIR analysers, add FTIR and QCL-IR analyser requirements and interference verification procedures, insert protocols and certificates for FTIR and QCL-IR analyser assessment, add fuel types including hydrogen, modify measurement procedures for dual-fuel hydrogen engines, and update related calculation methods and specifications throughout Annexes 4A, 4B and 11.

Proposal to amend para. 3.5.1. to include dual-fuel engines of Type 1A with hydrogen as gaseous fuel, amend para. 4.12.3.3.7. to establish a series of digits identifying dual-fuel engine types in the approval mark, insert new definitions for ‘Instrument manufacturer’ and ‘Type of analyzer’ in Annex 4 para. 3.1., insert new symbols and abbreviations in Annex 4 paras. 3.4. and 3.5., amend paras. 7.6.6., 7.7.4., and 8.1.1. to accommodate H₂O measurement and hydrogen engine calculations, amend para. 8.4.2.1., amend para. 8.6.2. to exclude CH₄ calculation when measured by FTIR or QCL-IR, amend para. 9.3.1.8. regarding gas drying, amend para. 9.3.2. to introduce FTIR and QCL-IR analyzers for CO, CO₂, CH₄, and NOx measurement with specifications in paras. 9.3.2.8. and 9.3.2.9., insert new para. 9.3.2.10. for independent analyzer assessment, amend para. 9.3.9. and para. 9.3.9.2.2. regarding interference effects and water quench checks, insert new paras. 9.3.9.5. and 9.3.9.6. for FTIR and QCL-IR interference checks, amend Annex 4 Appendix 2 para. A.2.1.2., amend Annex 4 Appendix 5 para. A.5.2., insert new Annex 4 Appendix 9 establishing procedure for H₂O measurement, insert new Annex 4 Appendix 10 for FTIR and QCL-IR analyzer assessment protocol, insert new Annex 4 Appendix 11 establishing model certificate for analyzer assessment, amend Annex 8 Appendix 1 paras. A.1.1., A.1.2.2., A.1.3.2.1., A.1.4.1., and A.1.4.3. for Type 1A hydrogen dual-fuel engines, amend Annex 15 paras. 4.2.2.3., 6.1., 10.3., and Appendix 4 paras. A.4.3.1., A.4.4.1.1., A.4.4.3.1., and A.4.4.3.3.

Proposal to replace para. 9.3.2.1., replace paras. 9.3.2.8.1. and 9.3.2.9.1., amend paras. 9.3.9.2.2. and 9.3.9.6., and insert new Appendices 10 and 11. The replacements clarify measurement principles, specify that analyser assessment may be conducted by type-approval authorities, designated technical services, or metrological institutes preferably via witnessed testing at the instrument manufacturer premises, and provide protocols and certificate models for analyser assessment. Amendments to para. 9.3.9.2.2. permit alternative humidification techniques and clarify that test gas shall be humidified to a water concentration approximately equal to the maximum water concentration expected during emission testing for all fuels. Amendment to para. 9.3.9.6. specifies that spectral resolution shall have a nominal value ≤0.5 cm⁻¹ to minimise cross interference.

Proposal to replace para. 9.3.2.8.1. and 9.3.2.9.1. to permit examination and verification of FTIR and QCL-IR analysers by type-approval authorities and designated technical services in addition to metrological institutes, preferably via witnessed testing at the instrument manufacturer’s premises, amend para. 9.3.9.2.2. to permit humidification techniques other than water bubblers and to clarify water concentration requirements for all fuels, and insert new Appendices 10 and 11 setting out a protocol for analyser assessment and a model certificate of acceptable analyser assessment.

Proposal to amend para. 9.3.2.1 in annex 4 to correct a paragraph number reference from ‘9.2.3.7.’ to ‘9.3.2.7.’ in the text describing measurement principles. The correction addresses a typographical error introduced in WP.29/2025/94.

Proposal to amend para. A.1.3.2.1. to modify the PEMS consistency check of exhaust mass flow and gas concentrations for fuels with a molar carbon to hydrogen ratio of 0. For such fuels, the formula in para. 8.4.1.6. of Annex 4 shall be used instead, with Equations 30 and 31 applied for Type 1A dual-fuel hydrogen engines. The verification shall not apply to engines operated on non-carbon fuels or dual-fuel engines when operated in dual-fuel mode with at least one fuel having a molar carbon to hydrogen ratio of 0.

Proposal to amend UN R49 to approve the use of hydrogen dual-fuel as a fuel in type approval of emissions for heavy-duty vehicles. The amendments introduce new requirements for measuring instruments such as FT-IR and QCL-IR, add symbols and specifications for hydrogen-fuelled engines specifying that only Type 1A hydrogen fuel is applicable, amend emission calculation formulas for ETC/ESC and WHDC test procedures, add new HO direct measurement methods for NOx wet correction calculation, and add declaration formats for FT-IR and QCL-IR approval.

Proposal to insert new definitions for ‘Instrument manufacturer’ and ‘Type of analyzer’, add symbols and abbreviations for hydrogen, water, ammonia, nitrogen dioxide, oxygen and particulates, add abbreviations for flame ionisation detector, Fourier transform infrared analyser, non-methane cutter and quantum cascade laser mid-infrared detection, amend provisions for hydrogen Type 1A dual fuel engines, modify fuel temperature requirements, insert procedures for water measurement using QCL-IR and FTIR analysers, add FTIR and QCL-IR analyser requirements and interference verification procedures, insert protocols and certificates for FTIR and QCL-IR analyser assessment, add fuel types including hydrogen, modify measurement procedures for dual-fuel hydrogen engines, and update related calculation methods and specifications throughout Annexes 4A, 4B and 11.

Proposal to amend para. 3.5.1. to include dual-fuel engines of Type 1A with hydrogen as gaseous fuel, amend para. 4.12.3.3.7. to establish a series of digits identifying dual-fuel engine types in the approval mark, insert new definitions for ‘Instrument manufacturer’ and ‘Type of analyzer’ in Annex 4 para. 3.1., insert new symbols and abbreviations in Annex 4 paras. 3.4. and 3.5., amend paras. 7.6.6., 7.7.4., and 8.1.1. to accommodate H₂O measurement and hydrogen engine calculations, amend para. 8.4.2.1., amend para. 8.6.2. to exclude CH₄ calculation when measured by FTIR or QCL-IR, amend para. 9.3.1.8. regarding gas drying, amend para. 9.3.2. to introduce FTIR and QCL-IR analyzers for CO, CO₂, CH₄, and NOx measurement with specifications in paras. 9.3.2.8. and 9.3.2.9., insert new para. 9.3.2.10. for independent analyzer assessment, amend para. 9.3.9. and para. 9.3.9.2.2. regarding interference effects and water quench checks, insert new paras. 9.3.9.5. and 9.3.9.6. for FTIR and QCL-IR interference checks, amend Annex 4 Appendix 2 para. A.2.1.2., amend Annex 4 Appendix 5 para. A.5.2., insert new Annex 4 Appendix 9 establishing procedure for H₂O measurement, insert new Annex 4 Appendix 10 for FTIR and QCL-IR analyzer assessment protocol, insert new Annex 4 Appendix 11 establishing model certificate for analyzer assessment, amend Annex 8 Appendix 1 paras. A.1.1., A.1.2.2., A.1.3.2.1., A.1.4.1., and A.1.4.3. for Type 1A hydrogen dual-fuel engines, amend Annex 15 paras. 4.2.2.3., 6.1., 10.3., and Appendix 4 paras. A.4.3.1., A.4.4.1.1., A.4.4.3.1., and A.4.4.3.3.

Proposal to replace para. 9.3.2.1., replace paras. 9.3.2.8.1. and 9.3.2.9.1., amend paras. 9.3.9.2.2. and 9.3.9.6., and insert new Appendices 10 and 11. The replacements clarify measurement principles, specify that analyser assessment may be conducted by type-approval authorities, designated technical services, or metrological institutes preferably via witnessed testing at the instrument manufacturer premises, and provide protocols and certificate models for analyser assessment. Amendments to para. 9.3.9.2.2. permit alternative humidification techniques and clarify that test gas shall be humidified to a water concentration approximately equal to the maximum water concentration expected during emission testing for all fuels. Amendment to para. 9.3.9.6. specifies that spectral resolution shall have a nominal value ≤0.5 cm⁻¹ to minimise cross interference.

Proposal to replace para. 9.3.2.8.1. and 9.3.2.9.1. to permit examination and verification of FTIR and QCL-IR analysers by type-approval authorities and designated technical services in addition to metrological institutes, preferably via witnessed testing at the instrument manufacturer’s premises, amend para. 9.3.9.2.2. to permit humidification techniques other than water bubblers and to clarify water concentration requirements for all fuels, and insert new Appendices 10 and 11 setting out a protocol for analyser assessment and a model certificate of acceptable analyser assessment.

Proposal to amend para. 9.3.2.1 in annex 4 to correct a paragraph number reference from ‘9.2.3.7.’ to ‘9.3.2.7.’ in the text describing measurement principles. The correction addresses a typographical error introduced in WP.29/2025/94.

Proposal to amend para. A.1.3.2.1. to modify the PEMS consistency check of exhaust mass flow and gas concentrations for fuels with a molar carbon to hydrogen ratio of 0. For such fuels, the formula in para. 8.4.1.6. of Annex 4 shall be used instead, with Equations 30 and 31 applied for Type 1A dual-fuel hydrogen engines. The verification shall not apply to engines operated on non-carbon fuels or dual-fuel engines when operated in dual-fuel mode with at least one fuel having a molar carbon to hydrogen ratio of 0.

Proposal to amend UN R49 to approve the use of hydrogen dual-fuel as a fuel in type approval of emissions for heavy-duty vehicles. The amendments introduce new requirements for measuring instruments such as FT-IR and QCL-IR, add symbols and specifications for hydrogen-fuelled engines specifying that only Type 1A hydrogen fuel is applicable, amend emission calculation formulas for ETC/ESC and WHDC test procedures, add new HO direct measurement methods for NOx wet correction calculation, and add declaration formats for FT-IR and QCL-IR approval.

Proposal to insert new definitions for ‘Instrument manufacturer’ and ‘Type of analyzer’, add symbols and abbreviations for hydrogen, water, ammonia, nitrogen dioxide, oxygen and particulates, add abbreviations for flame ionisation detector, Fourier transform infrared analyser, non-methane cutter and quantum cascade laser mid-infrared detection, amend provisions for hydrogen Type 1A dual fuel engines, modify fuel temperature requirements, insert procedures for water measurement using QCL-IR and FTIR analysers, add FTIR and QCL-IR analyser requirements and interference verification procedures, insert protocols and certificates for FTIR and QCL-IR analyser assessment, add fuel types including hydrogen, modify measurement procedures for dual-fuel hydrogen engines, and update related calculation methods and specifications throughout Annexes 4A, 4B and 11.

Proposal to amend para. 3.5.1. to include dual-fuel engines of Type 1A with hydrogen as gaseous fuel, amend para. 4.12.3.3.7. to establish a series of digits identifying dual-fuel engine types in the approval mark, insert new definitions for ‘Instrument manufacturer’ and ‘Type of analyzer’ in Annex 4 para. 3.1., insert new symbols and abbreviations in Annex 4 paras. 3.4. and 3.5., amend paras. 7.6.6., 7.7.4., and 8.1.1. to accommodate H₂O measurement and hydrogen engine calculations, amend para. 8.4.2.1., amend para. 8.6.2. to exclude CH₄ calculation when measured by FTIR or QCL-IR, amend para. 9.3.1.8. regarding gas drying, amend para. 9.3.2. to introduce FTIR and QCL-IR analyzers for CO, CO₂, CH₄, and NOx measurement with specifications in paras. 9.3.2.8. and 9.3.2.9., insert new para. 9.3.2.10. for independent analyzer assessment, amend para. 9.3.9. and para. 9.3.9.2.2. regarding interference effects and water quench checks, insert new paras. 9.3.9.5. and 9.3.9.6. for FTIR and QCL-IR interference checks, amend Annex 4 Appendix 2 para. A.2.1.2., amend Annex 4 Appendix 5 para. A.5.2., insert new Annex 4 Appendix 9 establishing procedure for H₂O measurement, insert new Annex 4 Appendix 10 for FTIR and QCL-IR analyzer assessment protocol, insert new Annex 4 Appendix 11 establishing model certificate for analyzer assessment, amend Annex 8 Appendix 1 paras. A.1.1., A.1.2.2., A.1.3.2.1., A.1.4.1., and A.1.4.3. for Type 1A hydrogen dual-fuel engines, amend Annex 15 paras. 4.2.2.3., 6.1., 10.3., and Appendix 4 paras. A.4.3.1., A.4.4.1.1., A.4.4.3.1., and A.4.4.3.3.

Proposal to replace para. 9.3.2.1., replace paras. 9.3.2.8.1. and 9.3.2.9.1., amend paras. 9.3.9.2.2. and 9.3.9.6., and insert new Appendices 10 and 11. The replacements clarify measurement principles, specify that analyser assessment may be conducted by type-approval authorities, designated technical services, or metrological institutes preferably via witnessed testing at the instrument manufacturer premises, and provide protocols and certificate models for analyser assessment. Amendments to para. 9.3.9.2.2. permit alternative humidification techniques and clarify that test gas shall be humidified to a water concentration approximately equal to the maximum water concentration expected during emission testing for all fuels. Amendment to para. 9.3.9.6. specifies that spectral resolution shall have a nominal value ≤0.5 cm⁻¹ to minimise cross interference.

Proposal to replace para. 9.3.2.8.1. and 9.3.2.9.1. to permit examination and verification of FTIR and QCL-IR analysers by type-approval authorities and designated technical services in addition to metrological institutes, preferably via witnessed testing at the instrument manufacturer’s premises, amend para. 9.3.9.2.2. to permit humidification techniques other than water bubblers and to clarify water concentration requirements for all fuels, and insert new Appendices 10 and 11 setting out a protocol for analyser assessment and a model certificate of acceptable analyser assessment.

Proposal to amend para. 9.3.2.1 in annex 4 to correct a paragraph number reference from ‘9.2.3.7.’ to ‘9.3.2.7.’ in the text describing measurement principles. The correction addresses a typographical error introduced in WP.29/2025/94.

Proposal to amend para. A.1.3.2.1. to modify the PEMS consistency check of exhaust mass flow and gas concentrations for fuels with a molar carbon to hydrogen ratio of 0. For such fuels, the formula in para. 8.4.1.6. of Annex 4 shall be used instead, with Equations 30 and 31 applied for Type 1A dual-fuel hydrogen engines. The verification shall not apply to engines operated on non-carbon fuels or dual-fuel engines when operated in dual-fuel mode with at least one fuel having a molar carbon to hydrogen ratio of 0.

Proposal to amend UN R49 to approve the use of hydrogen dual-fuel as a fuel in type approval of emissions for heavy-duty vehicles. The amendments introduce new requirements for measuring instruments such as FT-IR and QCL-IR, add symbols and specifications for hydrogen-fuelled engines specifying that only Type 1A hydrogen fuel is applicable, amend emission calculation formulas for ETC/ESC and WHDC test procedures, add new HO direct measurement methods for NOx wet correction calculation, and add declaration formats for FT-IR and QCL-IR approval.

Proposal to insert new definitions for ‘Instrument manufacturer’ and ‘Type of analyzer’, add symbols and abbreviations for hydrogen, water, ammonia, nitrogen dioxide, oxygen and particulates, add abbreviations for flame ionisation detector, Fourier transform infrared analyser, non-methane cutter and quantum cascade laser mid-infrared detection, amend provisions for hydrogen Type 1A dual fuel engines, modify fuel temperature requirements, insert procedures for water measurement using QCL-IR and FTIR analysers, add FTIR and QCL-IR analyser requirements and interference verification procedures, insert protocols and certificates for FTIR and QCL-IR analyser assessment, add fuel types including hydrogen, modify measurement procedures for dual-fuel hydrogen engines, and update related calculation methods and specifications throughout Annexes 4A, 4B and 11.

Proposal to amend para. 3.5.1. to include dual-fuel engines of Type 1A with hydrogen as gaseous fuel, amend para. 4.12.3.3.7. to establish a series of digits identifying dual-fuel engine types in the approval mark, insert new definitions for ‘Instrument manufacturer’ and ‘Type of analyzer’ in Annex 4 para. 3.1., insert new symbols and abbreviations in Annex 4 paras. 3.4. and 3.5., amend paras. 7.6.6., 7.7.4., and 8.1.1. to accommodate H₂O measurement and hydrogen engine calculations, amend para. 8.4.2.1., amend para. 8.6.2. to exclude CH₄ calculation when measured by FTIR or QCL-IR, amend para. 9.3.1.8. regarding gas drying, amend para. 9.3.2. to introduce FTIR and QCL-IR analyzers for CO, CO₂, CH₄, and NOx measurement with specifications in paras. 9.3.2.8. and 9.3.2.9., insert new para. 9.3.2.10. for independent analyzer assessment, amend para. 9.3.9. and para. 9.3.9.2.2. regarding interference effects and water quench checks, insert new paras. 9.3.9.5. and 9.3.9.6. for FTIR and QCL-IR interference checks, amend Annex 4 Appendix 2 para. A.2.1.2., amend Annex 4 Appendix 5 para. A.5.2., insert new Annex 4 Appendix 9 establishing procedure for H₂O measurement, insert new Annex 4 Appendix 10 for FTIR and QCL-IR analyzer assessment protocol, insert new Annex 4 Appendix 11 establishing model certificate for analyzer assessment, amend Annex 8 Appendix 1 paras. A.1.1., A.1.2.2., A.1.3.2.1., A.1.4.1., and A.1.4.3. for Type 1A hydrogen dual-fuel engines, amend Annex 15 paras. 4.2.2.3., 6.1., 10.3., and Appendix 4 paras. A.4.3.1., A.4.4.1.1., A.4.4.3.1., and A.4.4.3.3.

Proposal to replace para. 9.3.2.1., replace paras. 9.3.2.8.1. and 9.3.2.9.1., amend paras. 9.3.9.2.2. and 9.3.9.6., and insert new Appendices 10 and 11. The replacements clarify measurement principles, specify that analyser assessment may be conducted by type-approval authorities, designated technical services, or metrological institutes preferably via witnessed testing at the instrument manufacturer premises, and provide protocols and certificate models for analyser assessment. Amendments to para. 9.3.9.2.2. permit alternative humidification techniques and clarify that test gas shall be humidified to a water concentration approximately equal to the maximum water concentration expected during emission testing for all fuels. Amendment to para. 9.3.9.6. specifies that spectral resolution shall have a nominal value ≤0.5 cm⁻¹ to minimise cross interference.

Proposal to replace para. 9.3.2.8.1. and 9.3.2.9.1. to permit examination and verification of FTIR and QCL-IR analysers by type-approval authorities and designated technical services in addition to metrological institutes, preferably via witnessed testing at the instrument manufacturer’s premises, amend para. 9.3.9.2.2. to permit humidification techniques other than water bubblers and to clarify water concentration requirements for all fuels, and insert new Appendices 10 and 11 setting out a protocol for analyser assessment and a model certificate of acceptable analyser assessment.

Proposal to amend para. 9.3.2.1 in annex 4 to correct a paragraph number reference from ‘9.2.3.7.’ to ‘9.3.2.7.’ in the text describing measurement principles. The correction addresses a typographical error introduced in WP.29/2025/94.

Proposal to amend para. A.1.3.2.1. to modify the PEMS consistency check of exhaust mass flow and gas concentrations for fuels with a molar carbon to hydrogen ratio of 0. For such fuels, the formula in para. 8.4.1.6. of Annex 4 shall be used instead, with Equations 30 and 31 applied for Type 1A dual-fuel hydrogen engines. The verification shall not apply to engines operated on non-carbon fuels or dual-fuel engines when operated in dual-fuel mode with at least one fuel having a molar carbon to hydrogen ratio of 0.

Proposal to amend UN R49 to approve the use of hydrogen dual-fuel as a fuel in type approval of emissions for heavy-duty vehicles. The amendments introduce new requirements for measuring instruments such as FT-IR and QCL-IR, add symbols and specifications for hydrogen-fuelled engines specifying that only Type 1A hydrogen fuel is applicable, amend emission calculation formulas for ETC/ESC and WHDC test procedures, add new HO direct measurement methods for NOx wet correction calculation, and add declaration formats for FT-IR and QCL-IR approval.

Proposal to insert new definitions for ‘Instrument manufacturer’ and ‘Type of analyzer’, add symbols and abbreviations for hydrogen, water, ammonia, nitrogen dioxide, oxygen and particulates, add abbreviations for flame ionisation detector, Fourier transform infrared analyser, non-methane cutter and quantum cascade laser mid-infrared detection, amend provisions for hydrogen Type 1A dual fuel engines, modify fuel temperature requirements, insert procedures for water measurement using QCL-IR and FTIR analysers, add FTIR and QCL-IR analyser requirements and interference verification procedures, insert protocols and certificates for FTIR and QCL-IR analyser assessment, add fuel types including hydrogen, modify measurement procedures for dual-fuel hydrogen engines, and update related calculation methods and specifications throughout Annexes 4A, 4B and 11.

Proposal to amend para. 3.5.1. to include dual-fuel engines of Type 1A with hydrogen as gaseous fuel, amend para. 4.12.3.3.7. to establish a series of digits identifying dual-fuel engine types in the approval mark, insert new definitions for ‘Instrument manufacturer’ and ‘Type of analyzer’ in Annex 4 para. 3.1., insert new symbols and abbreviations in Annex 4 paras. 3.4. and 3.5., amend paras. 7.6.6., 7.7.4., and 8.1.1. to accommodate H₂O measurement and hydrogen engine calculations, amend para. 8.4.2.1., amend para. 8.6.2. to exclude CH₄ calculation when measured by FTIR or QCL-IR, amend para. 9.3.1.8. regarding gas drying, amend para. 9.3.2. to introduce FTIR and QCL-IR analyzers for CO, CO₂, CH₄, and NOx measurement with specifications in paras. 9.3.2.8. and 9.3.2.9., insert new para. 9.3.2.10. for independent analyzer assessment, amend para. 9.3.9. and para. 9.3.9.2.2. regarding interference effects and water quench checks, insert new paras. 9.3.9.5. and 9.3.9.6. for FTIR and QCL-IR interference checks, amend Annex 4 Appendix 2 para. A.2.1.2., amend Annex 4 Appendix 5 para. A.5.2., insert new Annex 4 Appendix 9 establishing procedure for H₂O measurement, insert new Annex 4 Appendix 10 for FTIR and QCL-IR analyzer assessment protocol, insert new Annex 4 Appendix 11 establishing model certificate for analyzer assessment, amend Annex 8 Appendix 1 paras. A.1.1., A.1.2.2., A.1.3.2.1., A.1.4.1., and A.1.4.3. for Type 1A hydrogen dual-fuel engines, amend Annex 15 paras. 4.2.2.3., 6.1., 10.3., and Appendix 4 paras. A.4.3.1., A.4.4.1.1., A.4.4.3.1., and A.4.4.3.3.

Proposal to replace para. 9.3.2.1., replace paras. 9.3.2.8.1. and 9.3.2.9.1., amend paras. 9.3.9.2.2. and 9.3.9.6., and insert new Appendices 10 and 11. The replacements clarify measurement principles, specify that analyser assessment may be conducted by type-approval authorities, designated technical services, or metrological institutes preferably via witnessed testing at the instrument manufacturer premises, and provide protocols and certificate models for analyser assessment. Amendments to para. 9.3.9.2.2. permit alternative humidification techniques and clarify that test gas shall be humidified to a water concentration approximately equal to the maximum water concentration expected during emission testing for all fuels. Amendment to para. 9.3.9.6. specifies that spectral resolution shall have a nominal value ≤0.5 cm⁻¹ to minimise cross interference.

Proposal to replace para. 9.3.2.8.1. and 9.3.2.9.1. to permit examination and verification of FTIR and QCL-IR analysers by type-approval authorities and designated technical services in addition to metrological institutes, preferably via witnessed testing at the instrument manufacturer’s premises, amend para. 9.3.9.2.2. to permit humidification techniques other than water bubblers and to clarify water concentration requirements for all fuels, and insert new Appendices 10 and 11 setting out a protocol for analyser assessment and a model certificate of acceptable analyser assessment.

Proposal to amend para. 9.3.2.1 in annex 4 to correct a paragraph number reference from ‘9.2.3.7.’ to ‘9.3.2.7.’ in the text describing measurement principles. The correction addresses a typographical error introduced in WP.29/2025/94.

Proposal to amend para. A.1.3.2.1. to modify the PEMS consistency check of exhaust mass flow and gas concentrations for fuels with a molar carbon to hydrogen ratio of 0. For such fuels, the formula in para. 8.4.1.6. of Annex 4 shall be used instead, with Equations 30 and 31 applied for Type 1A dual-fuel hydrogen engines. The verification shall not apply to engines operated on non-carbon fuels or dual-fuel engines when operated in dual-fuel mode with at least one fuel having a molar carbon to hydrogen ratio of 0.

Proposal to amend UN R49 to approve the use of hydrogen dual-fuel as a fuel in type approval of emissions for heavy-duty vehicles. The amendments introduce new requirements for measuring instruments such as FT-IR and QCL-IR, add symbols and specifications for hydrogen-fuelled engines specifying that only Type 1A hydrogen fuel is applicable, amend emission calculation formulas for ETC/ESC and WHDC test procedures, add new HO direct measurement methods for NOx wet correction calculation, and add declaration formats for FT-IR and QCL-IR approval.

Proposal to insert new definitions for ‘Instrument manufacturer’ and ‘Type of analyzer’, add symbols and abbreviations for hydrogen, water, ammonia, nitrogen dioxide, oxygen and particulates, add abbreviations for flame ionisation detector, Fourier transform infrared analyser, non-methane cutter and quantum cascade laser mid-infrared detection, amend provisions for hydrogen Type 1A dual fuel engines, modify fuel temperature requirements, insert procedures for water measurement using QCL-IR and FTIR analysers, add FTIR and QCL-IR analyser requirements and interference verification procedures, insert protocols and certificates for FTIR and QCL-IR analyser assessment, add fuel types including hydrogen, modify measurement procedures for dual-fuel hydrogen engines, and update related calculation methods and specifications throughout Annexes 4A, 4B and 11.

Proposal to amend para. 3.5.1. to include dual-fuel engines of Type 1A with hydrogen as gaseous fuel, amend para. 4.12.3.3.7. to establish a series of digits identifying dual-fuel engine types in the approval mark, insert new definitions for ‘Instrument manufacturer’ and ‘Type of analyzer’ in Annex 4 para. 3.1., insert new symbols and abbreviations in Annex 4 paras. 3.4. and 3.5., amend paras. 7.6.6., 7.7.4., and 8.1.1. to accommodate H₂O measurement and hydrogen engine calculations, amend para. 8.4.2.1., amend para. 8.6.2. to exclude CH₄ calculation when measured by FTIR or QCL-IR, amend para. 9.3.1.8. regarding gas drying, amend para. 9.3.2. to introduce FTIR and QCL-IR analyzers for CO, CO₂, CH₄, and NOx measurement with specifications in paras. 9.3.2.8. and 9.3.2.9., insert new para. 9.3.2.10. for independent analyzer assessment, amend para. 9.3.9. and para. 9.3.9.2.2. regarding interference effects and water quench checks, insert new paras. 9.3.9.5. and 9.3.9.6. for FTIR and QCL-IR interference checks, amend Annex 4 Appendix 2 para. A.2.1.2., amend Annex 4 Appendix 5 para. A.5.2., insert new Annex 4 Appendix 9 establishing procedure for H₂O measurement, insert new Annex 4 Appendix 10 for FTIR and QCL-IR analyzer assessment protocol, insert new Annex 4 Appendix 11 establishing model certificate for analyzer assessment, amend Annex 8 Appendix 1 paras. A.1.1., A.1.2.2., A.1.3.2.1., A.1.4.1., and A.1.4.3. for Type 1A hydrogen dual-fuel engines, amend Annex 15 paras. 4.2.2.3., 6.1., 10.3., and Appendix 4 paras. A.4.3.1., A.4.4.1.1., A.4.4.3.1., and A.4.4.3.3.

Proposal to replace para. 9.3.2.1., replace paras. 9.3.2.8.1. and 9.3.2.9.1., amend paras. 9.3.9.2.2. and 9.3.9.6., and insert new Appendices 10 and 11. The replacements clarify measurement principles, specify that analyser assessment may be conducted by type-approval authorities, designated technical services, or metrological institutes preferably via witnessed testing at the instrument manufacturer premises, and provide protocols and certificate models for analyser assessment. Amendments to para. 9.3.9.2.2. permit alternative humidification techniques and clarify that test gas shall be humidified to a water concentration approximately equal to the maximum water concentration expected during emission testing for all fuels. Amendment to para. 9.3.9.6. specifies that spectral resolution shall have a nominal value ≤0.5 cm⁻¹ to minimise cross interference.