VERT® 12th VERT Forum March 24th 2022 | eConference


About the VERT® Forum

The annual VERT Forum this year as e-conference is a one-day conference in cooperation with EMPA, the Swiss Federal Laboratories for Materials Science and Technology and AFHB, Vehicle Emissions and Powertrain Systems Laboratories.
Scientists and practitioners discuss the latest trends of Best Available Technology to minimize health and climate impact of combustion engine exhaust.

Participants are members of

  • Environmental and municipal traffic authorities
  • Indoor air cleaning community and HVAC
  • Public and occupational health authorities
  • Light and heavy duty vehicle manufacturers and operators
  • Manufacturers, operators of vessels, locomotives and airplanes
  • Public transport, harbor and airport management
  • Emission regulatory authorities and research institutes
  • Manufacturers of emission control technologies
  • Manufacturers of emission measurement equipment.




Working with a revised strategic approach to ensure the right focus in the future. Things are changing and we intend to keep following the vision of improving air quality by reducing negative impact of combustion technologies. A new CEO in 2022 will be given this challenge along with ongoing projects. NPTI will continue to be a key role, the marine industry is still in its infancy when it comes to emission control and VERTs participation in Horizon 22 project to eliminate particle emission from gasoline engines will keep us busy in the years to come. Further, is it the intention to investigate if conventional filter technology can apply to virus control and to look at alternative fuels and their environmental impact. VERT will be following the changes.
L. C. Larsen VERT Association


Health effect due to ultrafine solid particles of increasing concern?

The adverse effects of air pollution on human health have been well documented and implemented in the recent update of the Global Air Quality Guidelines of the World Health Organization (WHO) established in a series of major observational studies. Interestingly, WHO also refers to ultrafine particles having a negative impact on human health but it was concluded that insufficient information is available to propose guideline values. Yet, more than two decades of toxicological research has increased our understanding on ultrafine particles may have a different effect on human health compared to the larger (microns) particles that we inhale. This presentation will present an overview on the evidence to support this hypothesis, which emphasis on particles dosimetry, biodistribution and toxic potential.
F.Cassee, Prof.; RIVM; Netherlands

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SESSION 1 | New particle filters for gasoline engines - first fit and retrofit

New generation gasoline particulate filters for noncatalyzed applications and lowest particulate emissions

Corning will report on a new generation of gasoline particulate filters for uncatalyzed applications. This new generation of filters has been developed to enable very high filtration efficiency, in most cases above 90%, even in the totally fresh state and over aggressive drive cycles. At the same time the associated pressure drop penalty of these new technologies is moderate and under many practical conditions comparable to Gen 1 technologies. The performance of the new filter technology will be discussed based on experimental data obtained on several vehicles and under different emission cycles. The robustness of the new technologies will be assessed based on data generated on engine bench and real world mileage accumulation on public roads.
D.Rose; CORNING Germany

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New GPF for retrofit gasoline – a VERT-HORIZON project starting now

The EU-Commission set up a program for clean and competitive solutions for all transport modes including emission reduction for the in-use gasoline fleet. Retrofit emission reduction technology will therefore be required for cleaner, healthier air in urban centers. Within the frame of Horizon the EU commission has issued a call in September 2021 to develop solutions and demonstrate mature and commercially available GPF retrofit technology latest 2025. VERT as part of the consortium has passed the evaluation phase positively and will start this project in mid of 2022 with his partner companies and VERT members. With new Corning 2.0 substrates best available retrofit technology for uncatalyzed GPF will be demonstrated in 3-4 high mileage fleets, one of them in Israel. The project will also serve as a platform to continue research of the high emitter phenomena in general and demonstrate that new NPTI instruments are perfectly suited to eliminate the „dirty tail“ of the fleet. Both will be important contributions to systematically improve PN emission in megacities.
V. Hensel CEO; VERT-Association

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SESSION 2 | New applications for nanofilters

Brake wear particle emissions – Current state of play and future outlook

Particles emitted mainly due to brake, tire, and road wear – are expected to dominate traffic-related particulate matter emissions much earlier than 2030. Current braking systems are reported to be the most significant non-exhaust contributor of particulate matter to ambient air pollution. The scientific community, along with several regulatory bodies around the world, are investigating the topic of brake emissions from different perspectives. Despite the obvious research gaps – particularly in the field of possible adverse effects on human health – as well as various limitations mostly related to the lack of a standardized sampling and measurement method for characterizing brake particle emissions, there is a consensus that future regulation should limit particulate emissions from the foundation brakes. The United Nations Working Party on Pollution and Energy (UNECE GRPE) mandated PMP-IWG to develop a Global Technical Regulation (GTR) on brake emissions from Light-Duty Vehicles.
T.Grigoratos Dr. ; EU-JRC; Italy

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Brake dust particle filter

Assessing PM10 fine dust emission of a vehicle on a holistic base, published data yields a contribution of non-exhaust emissions of about 85 %. Neglecting resuspension, the sources are brake wear, road wear and tire wear. Preferred would be reducing emissions by avoiding them. For break wear full regenerative braking is foreshadowing on the horizon, but still a long way to go. Today’s friction braking system is quite complex but highly optimized. Instead of changing e.g. materials and hence friction parameters, a filtering device capable for retrofitting would be preferred. Challenges of adapting, evaluating a filter will be discussed and solutions shown.
Authors: Martin J. Lehmann, MANN+HUMMEL, Tobias Wörz, Lukas Bock

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Filtration of bioaerosols

With DPF fand GPF we have learned to literally eliminate soot and ash particles of the exhaust gas in the lung penetrating size range 10-500 nm and VERT certifies such systems since 25 years. Why not use these successful filtration structures also for cleaning breathing air from virus and bacteria, which are in the same size range? But how to protect people indoors close to infected persons from virus infection? NanoCleanAir, a Swiss startup of the VERT network, together with Swiss universities has investigated filtration and de-activation of viruses in different filter matrices and has developed a complete ventilation system to eliminate viruses by 99.9999 %, reduce cross contamination risk by over 99 % and reduce half time to clean contaminated rooms to 8 minutes. A classroom installation is perfectly working since 8 month and applications in, hospitals, elevator cabins, public transport and even aircraft cabines are on the way.
A.Mayer; NCA Switzerland

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SMF® - Innovative thin metallic filter media for industrial filtration applications

The known advantages of the thin, pleatable SMF® material, such as sharp separation efficiency at 10μm or good cleanability, shall be used for new industrial applications, like hot gas and liquid filtration. SMF® material is a mechanically and thermally highly stable filter medium, which can be pleated similar to paper or synthetic filter media. The SMF® base material is industrially manufactured as quasi endless sheet that is wound on a coil. The material is further processed into typical filter modules for the named applications. The performance of the medium is described by qualifying it according the corresponding standards of both oil filtration, e. g. multi-pass acc. ISO16889 and gas filtration in accordance with ISO16890 and e. g. VDI3926. Filter cartridges with ø 130 or 160mm up to 3m length are currently being tested for hot gas filtration and further developed to enable up to ca. 9m length. 
K.Schrewe; HJS Germany

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SESSION 3 | Particle Emission in marine applications

Air pollution from ships in the Mediterranean sea

Emission from sea going ships create a massive air pollution problem in harbors and near land. Up to 300 km the impact of these pollutions can be detected. In the Mediterranean Sea the ship traffic is quite intensive. Therefore, it isn’t surprising the measured values for particles and nitrogen oxide are high. But also the concentration of ozone due to the high emission level of the precursors is enormous. In the recent years, the impact of this emission came to the public  knowledge and abatement measures started. Very recently the Barcelona convention adopted a Sulfur Emission Control Area for the Mediterranean Sea and submit the request the IMO to introduce the SECA from the 1st of January 2025. For a NECA the discussion started.
A.Friedrich Dr.; Germany 

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Diesel particulate filters in marine use – performance evaluation after three years of service”

Danish Technological Institute has evaluated the performance of closed wall particulate filters which were retrofitted to the main and auxiliary engines in a Danish ferry. The filters have now been in operation for three years. We present our measurements techniques and results. We will also present another more recent demonstration project with closed wall DPF and urea-based SCR in a combined modular design, which can be installed as retrofit. This aftertreatment system is designed to be used with up to 1000 ppm (0.1 %) sulfur, which is the limit in the SECA zones. The system is expected to reduce emissions of NOx below the IMO Tier II limit and PM/PN below EU Stage V.
T.D.Pedersen Dr.; DTI ; Denmark

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A new membrane filter concept for HFO

Overall particulate emissions from ocean-going vessels are not much less than those from all land vehicles and are largely responsible for the melting of the polar ice caps. Because of the technical challenges, however, there have been no successful solutions so far and therefore no international regulations. A consortium under the leadership of VERT proposed a new technology with a ceramic membrane filter and pressure pulse cleaning, which should also be suitable for heavy fuel oil and for retrofitting. Test on engine benches with diesel oil and heavy fuel oil have shown that >99% filtration is achieved and periodic cleaning by compressed air is possible. The development however, was limited to a pilot test on a small scale and four-stroke engines. Because of its promising potential, this approach deserves broad further development and testing under real operational conditions, as there are still no alternatives in sight for this important environmental problem.
T.Lutz; VERT Switzerland

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SESSION 4 | New periodic technical inspection for DPF and GPF vehicles

Number based periodic technical inspection to improve roadworthiness

P.Szatmari EU-Commission (DG MOVE) Belgium

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Accelerating the NPTI flywheel!

In the former decade a dedicated test method for checking the PN emissions of diesel vehicles with a particulate filter (DPF) was developed. On the basis of these results the Dutch, Belgian and German governments decided to implement this particulate filter check (PFC) in 2022 and 2023. Meanwhile many developments and activities are on-going. More than 15 equipment manufacturers have developed low cost PN-counters and most of them are in the process of type approval. Furthermore UNECE prepares a revised Resolution R.E.6 on the administrative and technical provisions required for carrying out the technical inspections. Last year the European Commission investigated the performance of PTI particle counters. In a next step they will prepare a Recommendation for the particulate filter check. Currently detailed information of the PFC for policymakers, PTI-operators and emission professionals is available. Emission Training Services (ETS) recently published two books titled ‘Roet in beeld’ (Dutch) and ‘Particles Matter’ (English). More information is available on the webpage
G.Kadijk; ETS The Netherlands

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Calibration of PN-PTI instruments

The implementation of Particle Number (PN) counting under the auspices of Periodical Technical Inspection (PTI) legislation for certain Diesel vehicles in different European countries results into an unparalleled quantity of PN counters in the field. This poses the challenge of safeguarding ongoing compliance with regards to metrological performance of the PN counters for the respective national regulations. Besides measurement instrument performance the traceable calibration chain to national standards and a low measurement uncertainty are key targets to maintain a high quality PTI system reducing false passes and false failures. This presentation will address the various existing applicable legislations for the verification/calibration of PN PTI devices and Sensors´ approach to comply with them.
M.Heuser; SENSORS Germany

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SESSION 5 | Will Euro 7 cover toxicity of ultrafine particles indoor and outdoor

Secondary emissions from emissions control devices and their impact

How to choose the right filter, this was a key question and motivation to develop the VERT protocols. The VERT filter test is a stepwise approach that includes testing of filtration efficiency at defined engine loads both, with new and exposed filters, after >2000 h field operation. Also included is the VERT secondary emission test (VSET), which investigates effects of filters on toxic exhaust constituents and hazardous compounds that may form during filter regeneration and combustion of accumulated soot. Obviously also the fuel chemistry affects exhaust toxicity and filter performance. A motivation to develop a secondary emission test was the general opinion of VERT, and in some cases legal requirements, that any catalytic converter technology should not produce new pollutants. But what are relevant pollutants that particle filters, DeNOx-systems or combinations thereof can produce? What should be tolerated if a filter should get VERT approval? These questions on secondary emissions generated in emission control devices and their impact on occupational health and safety will be addressed.
N.Heeb Dr. ; EMPA Switzerland

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Emissions of handheld- and small engines ‘HaSMaNet’ <19kW

The persons working with the machines <19 kW are mostly in the near exposure. The emission limits for this group of machines have remained unchanged for many years at a level that is significantly higher than what is technically feasible. In this presentation we recall various conclusions that have been worked out in the course of many meetings. We mention the most important technical solutions and we draw attention once again to this significant neglect of the legislative progress.
J.Czerwinski VERT, Switzerland

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Particle emissions from mobile sources: Discussion of ultrafine particle emissions and definitions

At present there is no clear epidemiological evidence linking adverse human health effects to ultrafine particles (UFP), arguably because there is no universally agreed upon UFP definition. A commonly used definition is either particle number below 100 nm or total particle number, but without an agreed upon lower cut point. Another definition for UFP is total particle mass but without a commonly agreed upon aerodynamic diameter upper cut point. Yet another definition is lung deposited surface area weighted by lung deposition fraction, found mainly in the particle mobility diameter range from 20 to 400 nm. It is clear from these definitions that there are inconsistencies in the way UFP is used and defined in the literature. Sometimes these metrics are well correlated, sometimes not. For discussion, we suggest three new, metrics: UFP-N, UFP-M, and UFP-S, that we believe will add clarity. These metrics represent total number, mass, and surface area below 500 nm, respectively.
Kittelson D. Prof.Dr. ; Uni Minnesota, USA

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Why different approaches in the EU and the USA?

The evidence for concern [about ultrafine particle pollution] has grown substantially but falls short of being convincing to regulators for enacting general policies, especially at the national level.” This statement is in the preface of Ambient Combustion Ultrafine Particles and Health and captures well the current state of affairs in the policy debate in the US. But things are changing rapidly. While national standards will continue to be based on the mass of PM present in ambient air, a new precedent has been set. The US has proposed new aircraft engine emission standards that include non-volatile PM mass (mg/kN) and number (nvPM#/kN) limits. Will this action spillover to other sectors like motor vehicles or heavy-duty engine standards? Will this step increase the chances of alignment between US and EU standards, especially considering the Euro 7 proposal?
A.Ayala Dr. ; SMAQMD USA

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SESSION 6 | New markets and applications

UVAR in Jerusalem

The Jerusalem municipality's program to implement sustainable transportation via urban vehicles access regulations (UVAR) started in 2016 with a five- year program. The main step was promoting a Low Emission Zone (LEZ) for the entire city. The LEZ initiative involved a number of components: Our next UVAR step is initiating nonroad mechanical machinery (NRMM) legislation, which will be based on both the EU standards and the American standards. Our aim is to follow the same route as described for the LEZ. In this case the public campaign and negotiations will focus on the "Jerusalem Builders' Organization" which is the main construction union in the city. All the UVAR steps have been a result of excellent cooperation between the Jerusalem municipality, the ministry of environment in Israel, and the ReVeAL consortium.
N.Levy; Municipality Jerusalem Israel

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CALAC+ the climate and clean air program in Latin American cities

During its first phase, CALAC+ focused on providing technical assistance to promote enabling policies and regulatory conditions to reduce emissions from buses and nonroad mobile machinery (NRMM) in Bogotá, Mexico City, Lima and Santiago de Chile. Regarding buses emissions, CALAC+ contributed with studies related to the implementation and control of Euro 6/VI technologies, electromobility and vehicle environmental labelling strategies. The program also created a working group for Latin America in which three guidelines were issued for particle number measurements and inspections in buses equipped with diesel particulate filters (DPF). CALAC+ has played a key role in the region in raising awareness of NRMM emission problems, providing technical support for emission inventories calculations and the inclusion of regulatory pathways in government plans. CALAC+ conducted studies on the economic and environmental impacts of NRMM emissions reductions and developed 4 tools to transform technical information into practical inputs for policy writing.

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Low PN emission and BAT as well for engines > 560 kW

With emission standard “stage V” (2019) also emissions of diesel engines > 560 kW are now limited in Europe. However, the limit values for engines > 560 kW are higher than for engines < 560 kW and there is no particle number limit PN, which means that the gravimetric limit values can be achieved without the use of a wall flow DPF. The reasons, given for this decision were, that the fleet of construction machinery with engines > 560 kW in Europe is comparably small and these large machines usually do not operate in urban environments. Since 2019 however, new elements have been considered to also use best available technology for this high performance range: there are on one side reflections in Europe and also in the U.S.A. concerning the introduction of a follow up emission stage (Stage VI? / Tier5?) and on the other side the trend to introduce decentralized electric power stations powered by combustion engines to cover the risks of energy shortages during the difficult transition period to zero CO2 energy generation by solar and wind energy only. These plants will be close to consumers in urban areas, thus the question of BAT, in particular for exhaust gas particles, will gain importance.
F.Jaussi; LIEBHERR Swirtzerland

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