The chairman reviewed his discussion document with the main principles as technological neutrality and that requirements should be performance based, with Best Available Technology as the core.

Germany commented that the document later suggests excluding certain technologies (e.g. ‘open filters’) whereas such technologies would be capable of meeting the performance requirements. Euromot agreed with a performance-oriented approach but they would not like to see undefined wording like Best Available Technology (BAT) in the document.

The chairman said that to his view there should be separate approvals for systems that do not increase NO2 and ones that do increase NO2 (Issue 2 in his discussion document). Euromot noted that systems that reduce NOx would also reduce NO2.

The discussion document suggests 3 target approval schemes for systems that:
1). Reduce PM
2). Reduce PM and not significantly increase the direct emission of NO2;
3). Reduce PM as well as NOx and thus NO2.

AECC suggested adding a 4th point to cover systems that reduce NOx only. This was agreed.

Regarding national environmental classifications (section B of the chairman’s discussion document) it was clarified that there may be ‘intermediate’ classes as a result of retrofit (e.g. only PM limits for Euro IV). The chairman commented that in Anlage XXVII there is an additional minimum percentage reduction requirement. This is to allow for engines that are already close to meeting the next stage. He suggested that this should also be included in any future Regulation.

With regard to the operational cycle to be used for any validation tests (Issue 5 of the discussion document), it was suggested that HD engines should have no problem running transient cycles in addition to steady states, even if they were homologated only on the ESC cycle. For NRMM engines, there should be careful selection of engines as constant speed engines, for instance, do not run transient cycles.

The chairman commented that point D (secondary emissions) of his discussion document could be controversial. Germany commented that in Anlage XXVII there is a requirement that any additive used must first be approved. Germany also pointed out that VERT is a Swiss programme, not a Swiss-German programme as shown in the chair’s discussion document. AECC commented that development of test requirements to support measurement of secondary (unregulated) emissions is likely to be very time consuming.

Regarding durability (Issue 8), the chairman suggested that it would be a waste of all the work that had so far gone into VERT if the new requirements did not allow for the acceptance of existing VERT approvals. Euromot felt that any REC Regulation should stand on its own as it is a Regulation for new approvals; it should not rely on existing work. Euromot also felt that this section mixed durability and warranty. The two items should be separate – as they are in European Regulations. It was commented that the alternative durability requirements suggested in the chairman’s document (2000 hours and 100 cycles) are drastically different. The EC agreed that in principle alternatives could be allowed for a limited time period, but there needs to be some assessment of equivalence.

The chairman suggested that data from Inspection and Maintenance procedures could be used to cover in-service conformity (Issue 9). Germany noted that I&M programmes do not cover, currently, NOx and NO2. The chairman said that the reference value for the free Acceleration test would need to be changed as the original figure from Type Approval would have changed.

Regarding technology (Section F), the mandate from the EC is based on Euro VI requirements, so the group should consider whether the requirements should include PN and non-regulated emissions, the chairman said. He commented on the difficulty of upgrading engines to Euro VI overall. Article 10 to Euro VI Regulation (EC) No 595/2009 states that member states may grant financiel incentives for retrofitting in order to meet the Euro VI emission limits. The Commission expressed the opinion that the EU mandate would allow systems that met, for instance, only the PM requirements of Euro VI. Germany had a different view of the Euro VI text, that it permitted upgrading only to the full requirements of Euro VI. The Commission said that although this would have to be discussed further in Brussels, it should not need to be a consideration for this group as implementation should be a separate discussion from retrofit system certification. The EC felt that for this reason the group should cover requirements for PM control only, for PM with NOx control and for NOx control only. It would be possible to upgrade to Euro VI for PM, but NOx would be much more difficult. Any REC Regulation must, however, allow for upgrading of engines to Euro VI PM levels, the Commission said.

Issue 12 (bypassing and flow direction by design): the chairman noted that there are concerns over both bypassing and reversing the filter and he felt this should not be allowed. Germany noted that where there are safety requirements as a higher level of requirement than emissions (e.g. inland waterways), some form of bypassing might be necessary.

Issue 13 (efficiency): Hungary had commented that ambition levels other than Euro VI should be allowed but the chairman felt that the highest level would cover everything without resulting in unnecessary costs to retrofit system suppliers. He noted that there are currently no PN requirements for off-road but that diesel is classed by WHO as carcinogenic and so should be controlled by BAT. He suggested that there should be a percentage reduction requirement in addition to meeting Euro Stages, for engines that are already close to meeting the next highest limit.

Section 14 (NOx reduction efficiency): the chairman asked whether there should be ‘off cycle’ requirements which might mean that retrofit would have to meet higher requirements than original equipment.

Section 15 (shown in the document as a 2nd section 14 – suggested test procedure): AECC commented that the families for testing need to be determined before testing.

Germany said that because of the late distribution of the document, there could be further comments from Germany after internal discussions. The EC would need also time to consult.