Text adopted by the GRPE to amend Regulation No. 49 in order to establish provisions for the type-approval of heavy-duty dual-fuel vehicles.

Proposes the modifications (essentially corrections of mistakes) are derived from the text of document ECE/TRANS/WP.29/GRPE/2021/7 from Japan, related to UN GTR 04, as modified by Informal Document GRPE- 82-09

GRPE-approved text, based on a proposal prepared by the Euro VI Expert Working Group of the European Commission to revise the 06 series of amendments to UN R49 in order to address situations that were not covered by the latest series of amendments and to clarify the text.

Proposal to adapt certain requirements to the current state of technology and to transpose the latest decisions of the European Union (EU) regarding on-board diagnostics (OBD) threshold limits.

Proposal to

• align the requirements related to measurement equipment linearity verification with the Regulation No. 96,
• adapt the requirements related to fuel injection malfunction monitoring (On-Board Diagnostic systems) to the current state of technology, and
• correct the documentation requirements for off-cycle emissions.

Proposal to introduce provisions to align UN R49 with recently introduced stage D EU legislation in order enable manufacturers to continue to utilize the provisions in paragraph 4 of Annex 9A to approve light commercial vehicles with a light duty OBD architecture under this regulation. This proposal incorporates all of the provisions of the latest amendment to EU legislation. As stage D is unrelated to OBD, the proposal is to make stage C and all subsequent stages equivalent to EOBD 6-2. The proposal corrects

1. the constants for equation (34) to calculate exhaust mass flow using carbon balance method,
2. the constants used for CVS verification,
3. the formula for regression analysis according to Annex 4, Appendix 3, and
4. the rise time (to 3.5 s from 2.5 s) for the PEM analyzers under paragraph A.2.2.1. of the 06 series.

Proposal from GRPE to correct and clarify the text and to introduce linearity requirements for humidity sensors to address humidity content measurement for the calculation of the specific exhaust emission.

Proposal to correct drafting errors in the text.

Proposal to permit the use of hydrogen (H2) as fuel for emissions type-approval of heavy duty vehicles and to introduce an option to measure the total hydrocarbon (THC) emissions instead of measuring the non-methane hydrocarbon emissions in certain cases.

Proposal to remove additions to non-existing part of the 06 series of amendments (delete the PEMS PM number).