Mr. Schulte summarised the changes from the previous versions of the document.

In the section on scope, the UK-language changes as proposed by Mr. Davies had been adopted. Paragraph 2.6 (Contracting parties may choose to recognise other regulations as being equivalent to this regulation) was put into square brackets as it is believed that this is part of the 1958 agreement.

Section 3.4 has been clarified as “Category B retrofit emission control device (REC)” means a retrofit emission control device which is intended to control particulate matter emissions only, and which does not increase the direct NO2 emissions by more than ²⁰% based on the engine out [NO2] level. It was agreed that the term ‘engine baseline emissions’ would be used with a definition of that term as covering the engine with any existing aftertreatment, depending on the emissions level. There was further discussion on the percentage figure. It was agreed that this would depend on the stringency of the eventual procedure. The highlighted text from CARB under section 3.4 can now be deleted.

It was also suggested that section 3.5. (“Category C retrofit emission control device (REC)” means a retrofit emission control device which is intended to control NOx emissions only) should exclude systems that control NOx but increase PM. The availability of data on the effects of NOx control systems (especially SCR) on PM number was discussed, including the availability of VERT results and the ACEA database for Euro VI. In discussion it was felt that if required this could be covered under the requirements on effects on other regulated pollutants or under the Annex on secondary emissions. This could, for instance, be a requirement to demonstrate no significant increase in PM Number. Another option would be to limit, for the time being, this section to SCR. Following this discussion it was agreed not to include a PM Number requirement in section 3.5.

Mr. Galey commented that in Section 3.6 (“Category D retrofit emission control device (REC)” means a retrofit emission control device which is intended to control both particulate matter emissions and NOx emissions, and thus NO2 emissions) there could be systems that reduced NOx but not NO2.

The term ‘PN’ has been modified throughout the document to ‘PM number’ to align with the wording used in Euro VI.

Text had been added (currently under section 3.29) to cover cases where modifications to the Original Equipment specifications are necessary, requiring the applicant submit additional test data, engineering justification and analysis and to get OEM permission for any changes to the original emissions control system.

The tables in section 4 have been updated. Following discussion it was agreed table 4.4 would be revised to reflect the fact that some NRMM limits are framed in terms of HC+NOx.

Under section 5.5 an accelerated aging procedure was to be provided by Bosal, but this has not yet been received.

Mr. Williams pointed out that the requirement to use the same test bed for tests before and after the field durability test may be difficult to achieve in practice. Over 1000 hrs elements of the equipment in any given test cell may have changed.

Corrections need to section 5.1 a) were noted (the category referred to should be M, not M1 and the mass should be the reference mass).

The issue of durability tests was considered in detail, including the length of the durability requirements, the possibility of requiring field durability rather than permitting bench tests, and a suggestion to include a vibration test in conjunction with bench testing. The latter option was rejected but it was agreed that there could be a general ‘robustness’ requirement that the manufacturer must ensure general durability in real use. Participants were asked to propose suitable text. Also text in the CARB document on installer responsibility could be examined.

In section 6.1 c) the wording was revised to “Minimum total charge of catalytically active materials of the particulate reduction system including upstream catalysers (if fitted) (in g)”. The definition of particulate reduction system will be extended to include DOCs. Participants will also consider whether the charge should be framed in terms of mass only or as mass per unit volume. It was agreed that the type of catalytically active material should also be specified in section 6.1.

Under section 10 the CARB reference on space velocity has still to be traced.

Under section 12 the base emissions level for the particulate reduction family also needs to be specified.

The effect on performance or durability of the fitment of a given system to different engines, under the family criteria, was examined. It was felt that key issues such as exhaust back-pressure are covered by the proposals. This led to a discussion on the need for market surveillance and/or periodical inspection to ensure in-service durability, but it was eventually agreed that this cannot be an issue of this regulation.

The Annex on measurement of secondary emissions is currently a ‘cut and paste’ from the Swiss SNR 277205 (VERT) standard. Text needs to be adapted to this draft and it needs to make clear that secondary emission testing is not directly linked to each type approval measure. The requirements in SNR 277205 cover NO2, VOCs, oxidised VOCs (such as aldehydes), PAHs, nitro-PAHs, PCDD/F and catalytically active elements (metals). It was noted that Euro VI and the NRMM regulations already include requirements on ammonia. In Switzerland there are no specific limits for these secondary emissions – the technical authority has to decide whether the results are ‘state of the art’. Some participants felt that the cost and time implications would be significant and that the type of equipment specified is not available in most emissions laboratories. It was suggested that the likelihood of such emissions should be assessed to evaluate the need for controls in this regulation and the chairman suggested that the requirement could be satisfied by referring to existing tests of similar materials unless a new type of material were to be used in the emissions reduction system. In response for the need to then provide guidance, it was reported that this issue is being considered by the European Commission and the conclusions from this could be adopted when completed.

In was felt that EMC (electromagnetic compatibility) requirements would be covered by the EMC Directive. It was also suggested that there should be requirements on maintenance documentation.