Official technical report detailing the rationale and decision-making behind the development of Amendment 2 (Development Phase 2a) of GTR No. 15.

Draft text pursuant to the drafters’ group session.

European Commission, Japan, and other stakeholder comments.

Abstract from JSAE chassis dynamometer testing working group with particular regard to 4WD chassis dynamometer.

Proposal to correct and clarify the text, including to

1. correct the constants for equation (34) to calculate exhaust mass flow using carbon balance method,
2. correct constants used for CVS verification,
3. correct the formula for regression analysis according to Annex 4, Appendix 3, and
4. correct 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.

The purpose of the low temperature test is to check the level of specific pollutant emissions of vehicles in conditions that may easily be encountered during the winter season.

Summary of the results of the Annex 4 Interest Group work under phase 2a of the development of GTR No. 15.

Comprehensive amendment of document GRPE/2017/6 to align UN R49 with the latest amendments of EU Euro VI legislation (Reg. EU 2016/1718), including

1. OBD equivalency option for light commercial vehicles to be continued with step ‘D’,
2. editorial corrections (incl. keeping optional THC PEMS measurement for gas engines),
3. implementation dates in Appendix 9 table 1 (2016/1718) and Annex 3 table 1 (R49),
4. implement rejection note for retroactive applicability with regard to in-service conformity (paragraph 13.4.),
clarification of type approval provisions for ‘new vehicle types as of 2017’,
5. deletion of infeasible requirement related to the PEMS test (“…void if … no valid windows left in urban only”), second part of sentence in Annex 8, Appendix 1: A1.4.2.2.2.2.
6. deletion of inconsistency between work based window and CO2 mass based method regarding valid integration windows (A.1.4.2.2.2.2. versus A.1.4.3.1.2.2).