DownToTen · Project

Measuring Ultra-Fine Vehicle Exhaust Particles That Current Regulations Miss

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Right now, car emission tests only catch particles bigger than 23 nanometers — but engines also spit out even tinier particles that slip through the net. Think of it like a fishing net with holes too big to catch the smallest fish. This project built instruments and a portable measurement system that can detect exhaust particles down to 10 nanometers, tested on real roads with real cars. The results feed directly into future EU regulations that will tighten the rules on what cars are allowed to emit.

By the numbers

10 nm

Minimum particle size measurable (down from 23 nm regulatory limit)

23 nm

Current regulatory particle measurement threshold

Consortium partners across 7 countries

Total project deliverables completed

Industrial partners in the consortium

The business problem

What needed solving

EU regulators are preparing to tighten vehicle emission standards below the current 23nm particle threshold, but automakers and testing companies lack reliable, portable instruments to measure these ultra-fine particles under real driving conditions. Without accurate sub-23nm measurement, companies cannot certify compliance with upcoming rules or optimize their engines for the new limits.

The solution

What was built

The project delivered a working PN-PEMS demonstrator unit — a portable system for measuring particle number emissions down to 10 nanometers — along with a synthetic aerosol calibration bench, a validated sampling methodology for sub-23nm particles, and proposed conformity factors for future vehicle type approval. In total, 20 deliverables were completed.

Audience

Who needs this

Automotive emissions testing equipment manufacturersCar OEMs with direct injection gasoline and diesel engine linesVehicle type approval and homologation servicesEmissions regulatory consultancies advising on EU complianceAftermarket exhaust and filtration system developers

Business applications

Who can put this to work

Automotive emissions testing equipment

mid-size

Target: Companies manufacturing portable emissions measurement systems (PEMS)

If you are an emissions measurement equipment manufacturer dealing with the upcoming shift to sub-23nm particle regulations — this project developed and tested a PN-PEMS demonstrator unit capable of measuring particles down to 10 nanometers under real-world driving conditions. The methodology and calibration approach from 20 deliverables gives you a head start on building compliant next-generation instruments before regulations tighten.

Automotive OEM and powertrain engineering

enterprise

Target: Car manufacturers with direct injection gasoline and diesel engine lines

If you are an automaker needing to understand how your direct injection gasoline or diesel engines perform under future sub-23nm emission limits — this project mapped the formation, origin, and chemical character of nanoparticles below 23 nanometers from exactly those engine types. The real-world driving emission (RDE) test results and proposed conformity factors help you design cleaner combustion systems before the rules change.

Vehicle type approval and regulatory compliance

any

Target: Technical services and homologation bodies certifying vehicle emissions

If you are a type approval authority or testing service preparing for stricter particle number limits — this project proposed a complete sampling and measurement methodology for sub-23nm particles, validated across 9 consortium partners in 7 countries. The findings on conformity factors and emission limits are designed to feed directly into future EU vehicle and engine type approval procedures.

Frequently asked

Quick answers

What would it cost to adopt this measurement technology?

The project did not publish pricing data. However, the PN-PEMS demonstrator was built from evaluated existing and under-development instruments, suggesting costs comparable to current PEMS equipment with modifications for the sub-23nm range. Contact the consortium for licensing or partnership terms.

Can this work at industrial scale for production-line testing?

The demonstrator was tested both in laboratory settings and under real-world driving conditions (RDE), which shows it works outside controlled environments. Scaling to production-line use would require engineering for durability and throughput, but the portable form factor of the PEMS demonstrator is a strong starting point.

What about intellectual property and licensing?

The project produced 20 deliverables including the PN-PEMS demonstrator unit. As an RIA (Research and Innovation Action) project coordinated by Aristotle University of Thessaloniki with 3 industrial partners, IP is likely shared across the 9-partner consortium. Licensing terms would need to be negotiated directly.

How does this relate to upcoming EU emission regulations?

The project was specifically designed to assist in determining future particle number emission limits and conformity factors for vehicle type approval, primarily for Real Driving Emissions (RDE). Results directly inform regulators on how to extend measurement requirements below the current 23nm threshold.

What particle sizes can this actually measure?

The project developed methodology to measure particles down to at least 10 nanometers, well below the current regulatory cutoff of 23 nanometers. This was validated using a synthetic aerosol bench for calibration and tested on both direct injection gasoline and diesel engines.

Is this ready to use today or still experimental?

The project ran from 2016 to 2019 and produced a working PN-PEMS demonstrator unit that was tested in both lab and real-world conditions. Based on available project data, the technology has been demonstrated but would need further product engineering for commercial deployment.

Consortium

Who built it

The DownToTen consortium brings together 9 partners from 7 countries (Austria, Belgium, Germany, Greece, Finland, Italy, UK), with a balanced mix of 4 universities, 2 research organizations, and 3 industrial partners (33% industry ratio). Coordinated by Aristotle University of Thessaloniki in Greece, this spread across major European automotive markets — particularly Germany, Italy, and the UK — gives the results credibility with both regulators and automakers. The presence of industrial partners alongside academic labs means the measurement methods were tested with real-world applicability in mind, not just theoretical accuracy.

ARISTOTELIO PANEPISTIMIO THESSALONIKISCoordinator · EL
RICARDO CONSULTING ENGINEERS LIMITEDparticipant · UK
TECHNISCHE UNIVERSITAET GRAZparticipant · AT
CENTRO RICERCHE FIAT SCPAparticipant · IT
TECHNISCHE UNIVERSITAET MUENCHENparticipant · DE
TAMPEREEN KORKEAKOULUSAATIO SRparticipant · FI
AVL LIST GMBHparticipant · AT
RICARDO-AEA LTDthirdparty · UK
JRC -JOINT RESEARCH CENTRE- EUROPEAN COMMISSIONparticipant · BE

How to reach the team

The project was coordinated by Aristotle University of Thessaloniki (Greece). SciTransfer can facilitate an introduction to the research team.

Order a report on this consortium See ARISTOTELIO PANEPISTIMIO THESSALONIKIS profile →

Next steps

Talk to the team behind this work.

Need to understand how sub-23nm particle regulations will affect your products? SciTransfer can connect you with the DownToTen team for licensing, consulting, or technology transfer.

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