29. The representative from CITA introduced GRPE-81-18 and GRPE-81-19 proposing the introducing of Particulate Number (PN) reference value tests in UN Regulations Nos. 24 and 83, that could be used, for example, as part of roadworthiness tests during the lifetime of the vehicle. The representative from CITA explained this first introduction to the documents was primarily aiming at gathering the interest of GRPE to work on such issue.

30. The representative from OICA regretted that both informal documents had been submitted soon before GRPE, and therefore limited time was available to carefully study the proposals. He highlighted GRPE-81-19 was not in line with GRPE-81-28 proposed by OICA (para. ‎32). He finally wondered if the proposals from OICA would have an impact on the cost of Periodic Technical Inspections (PTI).

31. The representative from EC deplored a premature proposal given the importance of the issue for assessing Diesel Particulate Filters (DPFs) deterioration. She stated the EC would be willing to redefine the test included in UN Regulations Nos. 24 and 83 to include PN. The representatives from NL, which is likely to include PN tests during PTI as of 2021, declared his willingness to work on a more refined proposal. The representative of Germany also supported the initiative and stated he would be happy to contribute.

32. The representative from OICA briefly introduced GRPE-81-28 proposing to remove UN Regulation No. 24 from the scope of UN Regulation No. 49. The representative from EC underlined such proposal was not on the table at this stage.

33. The Chair proposed GRPE to consider a full package during the next session of GRPE in January 2021 including the views of stakeholders having shown interest to work on the topic.