Consolidated version integrating GRBP/2022/13, GRBP/2022/16 and GRBP-76-09 as adopted during the 76th GRBP session and including corrections and clarifications per GRBP/2023/12.

Proposal from the Informal Working Group on Measurement Uncertainties (IWG MU) to amend UN R51 with tables showing the measurement uncertainties when performing type-approval, COP, or field testing (e.g. market surveillance).

The measurement uncertainties developed in this Appendix are based the IWG MU work and its Document for Reference which describes a general approach to estimate measurement uncertainties (GRBP/2022/9/Rev.2). The impact of the quantities on the expanded uncertainty has been evaluated separately for run-to-run, day-to-day, vehicle-to-vehicle and site-to-site variations. Some of the different impacts are based on calculations from tolerances in Annex 3, while others are based on experiences.

Proposal to clarify the details of the data-handling during the monitoring phase required in paragraph 5.1.1.

Proposal from the Informal Working Groups on Measurement Uncertainties (IWG MU) and Additional Sound Emission Provisions (ASEP) and from the International Organization for Standardization (ISO) for editorial corrections and clarifications based on the 03 series of amendments to UN R51 up to Supplement 7.