The Chairman opened the meeting and welcomed the participants.
The agenda 30-01 was adopted unchanged.

B. Giechaskiel (JRC) presented the draft guidelines for standardising measurement of sub-23 nm particles. The presentation (30-02) also included information on regeneration.

There was significant discussion on the specification / details for the catalytic stripper (CS) – JRC reported that they had tested 3, with and without sulphur trap.

• Characterisation of losses – propane (gas) / tetracontane (PN/ add SO2 to see when get breakthrough.
• Formulation
• Position

Ricardo-AEA and Horiba proposed CS with regenerative S-trap to avoid that it has to be sized for one year operation.

Discussion on CPC specification – eg how to define a 10nm CPC. TSI suggested for 10 nm CPC, that 50% cut off at 10nm, 90% at 20nm. Noted that a smaller D90 would be challenging. A 50-70% efficiency at 10nm would include many of the the existing CPCs

Agreed to review aircraft industry work with 10nm CPCs (no CS) and noted that JRC might be included in the German project on CS.

Next steps:

• JRC to issue an updated document, clearly defining the open points.
• Measurement data using guideline protocol to be gathered and reviewed for future discussion. Timeline approx. 12 months.
• H-G Horn to consider what it would take to re-use existing CPCs vs starting again.
• Horiba report 2014-01-1604 (publication due April 2014) to be reviewed as includes attempt to characterise CS
• Bochum report on Aircraft measurements expected soon.

PMP-30-02 | PMP: Sub 23 nm measurement recommendations

PMP-30-09 | Review on engine exhaust sub-23 nm particles Draft copy for PMP informal group comment of the JRC Science and Policy Report.

JRC contracted Ricardo-AEA. Presentation provided by B. Giechaskiel.

• Heavy Duty include regeneration PN measurements – continuous and periodic, however, PN measurements during regeneration are currently excluded from light duty emissions requirements.
• Regen measurements with 10nm and 23nm CPCs show no indication of artefact. The artefact shows up in the 6nm measurements.
• Considering the PN-PEMs project for RDE in Europe, useful to consider how regeneration in real driving situation compares to regeneration in a laboratory.
• Clear need identified to ensure pre-conditioning occurs prior to testing post-regeneration.
• Identified need to consider regen from multi-device aftertreatment systems (eg either LNT or SCR and DPF.
• Essential to use Euro 6 vehicles .
• JRC test plan (under revision) for diesel regeneration aims to start Sept 2014 in parallel with PN-PEMS. JRC will use the WLTC as the cycle for study basis.
• Further discussions on issues with measuring regeneration on GPF (passive rather than active regen) – agreed to review in 1 month by web conference and tentatively to cancel the GRPE PMP session.

PMP-30-03 | Particle measurement: Regeneration issues

PMP-30-07 | Particle measurement during regeneration of GPF and DPF Discussion presentation on issues potentially impacting the measurement of PN during regeneration of gasoline particulate filters and diesel particulate filters on light-duty vehicles.

The VPR calibration report is currently unchanged – the recommendations from JRC were added to the report as comments .

The CPC calibration document is also unchanged.

Both documents to be uploaded to PMP website with request for comments.

Agreed – only to consider updates in relation to 23nm at the present time. A further update to 10nm would be made when more information is available.

Next meeting – BERN GPF presentation

PMP-30-04 | PMP: Volatile Particle Remover calibration issues

PMP-30-10 | Volatile Particle Remover Calibration and Validation Procedures This document describes the calibration and validation procedures for the VPR. Calibration of the VPR is to be performed at the point of manufacture and validation is to be performed at least at 6 month intervals for all instruments without automatic temperature sensors or at least at 12 month intervals if automatic temperature sensors are present. The calibration procedure must be repeated if the system ‘fails’ its validation procedure or the particle number measurement system is modified in any way.

PMP-30-12 | PMP draft recommendations for <23nm measurements

Hans-Peter Andres (METAS) gave an overview of the EMRP-ENV-02 project and the 6 deliverables and status to date. Final workshop 13-14 May 2014.
Key conclusions:

• Counting efficiency is material dependent (slide 14)
• ‘Soot likeness’ is not a good criterion as soon is intrinsically variable
• Primary calibration – recommends heterogenous nucleation of silver (using seed particles) as allows larger monodisperse size
• However, delivery to field needs a less onerous method.
• Uncertainty chain (traceability) from electrometer to CPC completed
• All 6 deliverables achieved, however, several reports still in progress.
• See link on Slide 26 for additional information

Discussion on how to translate the above into a practical chain of work – eg primary calibration by silver particles would mean sending CPC to METAS.

Secondary aerosol and transfer functions – eg could be emery oil as long as traceability through the silver particles. H-G Horn briefly outlined a procedure for traceability.

PMP-30-11 | Measuring soot particles from automotive exhaust emissions Summary of the PN calibration project under the European Metrology Research Programme's project on "emerging requirements for measuring pollutants from automotive exhaust emissions" (EMRP ENV-02).

Co-Decision part of the legislation to be finalised by end April 2014 with delegated Act to be adopted in 18-24 months on the test methods and other practical aspects.
Co-Decision part will contain the essential elements – i.e scope and limit values
PN limit values will be established for:

• 56 – 560 kW : land based engines
• >300 kW : inland waterway transport
• All rail cars (note locomotives out of scope)

Mr Troppmann (DG-ENTR) confirmed that EU Com very keen on PMP activities. Have contracted JRC to study but 1-2 engines required, timing preparation until end 2014, testing during 1st half 2015.

Proposal as per Swiss ordinance : 1E+12 #/kWh – in line with PM limits as tried to correlate stringency of PM and PN limits.

J Andersson (Ricardo AEA) presented overview of NRMM situation and open questions –

• eg Slide 11 – considering partial flow measurement instead of CVS
• Open crankcase ventilation issues (slide 12) with oil mist via mini CVS to prevent damage to measurement side by analyser contamination. Noted blow-by gas measurement already required.
• Areas for further study identified on slide 17.

Discussion of HD Euro 6 idea to move to raw PN measurement with extra fixed dilution stage prior to PND1. Not confirmed if this proposal is being taken forward.

• <56kW : PN will apply for CI engines only
• >56kW : PN will apply to both CI and SI engines
• Questions remain on CNG SI and CNG CI dual fuel engines
• Fuel = 10 ppm S

PMP-30-08 | Potential Issues Related to the Measurement of PN During Regeneration of NRMM

Theodoros Grigoratos (JRC) presented the summary of the investigation which covered PM10 emission factors for non-exhaust particles.

Some discussion of an example of a damage cost scenario – after some discussion this was removed from the presentation as the scenario was theoretical only and was not not technically feasible to achieve.

Noted there is very little information on clutch wear, nearly nothing since 1990 when asbestos was removed, however, as most modern clutches are contained, there is probably no need to study this further.

REBRAKE study ongoing – objective : 50% reduction on brake emissions

M Gustaffson – VTI presented findings on interaction of tyre/road wear particles:

• Road dust = suspension and resuspension
• Considered different tyre types & different pavement types and used wet dust sampling
• Noted pavements in Sweden / Norway / Finland well adapted to run studded tyres w/o excessive PN emissions
• Slide 23 gives details of an expert working group on road dust.

Following discussion of what PMP should consider and where PMP could contribute to the work, it was agreed that brake and tyre / road wear measurement methods could be in scope for PMP but resuspended road dust out of scope because no vehicle regulation relevant.

PMP-30-05 | Particulate matter emissions from tyres and brakes: Main facts and open issues Review of findings from the review of literature on particle emissions from non-exhaust sources covering tires and brake materials.

PMP-30-06 | Presentation on REBRAKE program Presentation on <a href="http://www.rebrake-project.eu/Pages/home.aspx" target="_blank">REBRAKE, the European Commission-supported project</a> to better understand brake-wear emissions and their impact on air quality.

PMP-30-13 | VTI presentation: Non-exhaust particles Presentation on Swedish and Scandinavian research into sources and impact of non-exhaust airborne particles, including from wear on roads, tires, brakes, and similar sources.

Web Conference in April / May ahead of GRPE. Date via doodle poll.