32. GRPE agreed to consider a presentation from the representative from the US on the recent proposed rule for Heavy Duty tailpipe emissions (GRPE-86-33) released by US EPA. The representative from the European Commission asked about how the future share of zero-tailpipe emission vehicles (ZEVs) had been calculated, and which kind of ZEVs had been considered. The representative from the US clarified the mandates in certain parts of the US, such as in California had been used as a reference and that no fuel cell vehicles were assumed in the time frame studied. He also added that for example, school buses were assumed to be electrified first, as a vehicle category in which the payback time would be quick and the driving patterns would match the vehicle technical specifications.

33. The Chair asked whether during the development of the US proposed rule, existing UN legal instruments such as UN GTRs Nos. 4 or 10 were taken into consideration. The representative from the US confirmed that the World Heavy-Duty test Cycle (WHDC) was considered but abandoned during the consultation process, as well as off cycle emissions where alignment would still require additional changes in the procedure. He confirmed that the US (through the US EPA) remained committed to harmonize regulation through GRPE.

34. The representative from the European Commission offered to introduce the Euro7/VII proposal at the next session of GRPE, proposing to hold any further discussions about necessary changes in UN GTRs until then. The Chair highlighted the importance of harmonizing provisions, especially on the heavy duty sectors, and invited GRPE to reconsider this topic at the forthcoming sessions of GRPE.