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Improving Air Quality in European Rail

Improving Air Quality in European Rail

Aug 10, 2026 | Uncategorized

 

Air quality is an important aspect of passenger comfort and protection in enclosed railway environments. Air circulating through HVAC systems can contain fine particles, dust and airborne microbes, including viruses and bacteria, creating a need for effective filtration solutions.

The solutions

The two PEPA-F solutions designed by Europe’s Rail (EU-Rail) address two complementary aspects of air filtration in railway environments.

PEPA-F Pathogen Filter

The PEPA-F Pathogen Filter provides passive mechanical air filtration filtration to capture and eliminate microbes, including viruses and bacteria. Some data:

  • Virus activity reduction: 8% (ISO 18184).
  • Bacteria activity reduction: 99,9% (ISO 20743).
  • Particulate reduction: up to ePM1 50% (ISO 16890).

Readiness for Industrialisation and Deployment

Prototypes have been tested for DIRK trains. Further deployment is subject to the validation results. The solution is mature for other types of trains.

Maturity level

TRL 6/7

Expected benefits

  • 6 weeks, with scalable dimensions for any existing fleet.
  • No installation risks, as no interface changes are required.
  • Protection of passengers, technical staff and drivers against microbes.
  • Contribution to restoring confidence in public transport.
  • Long filter lifetime.

PEPA-F Particulate Filter

PEPA-F is a passive mechanical air filtration solution for the capture of fine particles and dust.

Some data:

  • Performance at a pressure drop of ~ 60Pa at 2m/s.
  • Particle reduction: ePM1 >50% (ISO 16890).
  • Fire and smoke certified (EN45545 – HL3).

Readiness for Industrialisation and Deployment

Three prototypes have been tested for NAT train. Further deployment depends of the validation results. The solution is mature for other types of trains.

Maturity level

TRL 7

Expected benefits

  • 6 weeks, with dimensions scalable to any existing fleet.
  • No installation risk: no interface changes.
  • Protection of passengers, technical staff and drivers against particulate matter and dust.
  • Support for WHO recommendations and ASHRAE guidance. Protection of the HVAC unit.

Who benefits

Infrastructure managers

Railway operators

Suppliers

Conclusion

The versatility of the two PEPA-F solutions makes them suitable for a wide range of railway applications. Both solutions can be used with:

  • all HVAC (Heating, Ventilation & Air Conditioning) systems,
  • all types of trains, including tramway, metro, commuter, regional and high-speed trains
  • all platforms (new build, in-service, modernisation).

This broad applicability provides a solution that can be integrated across different railway environments. With a filtration market of approximately €20 million, representing 1% of the market, and a filtration growth rate of about 5% per year, the solutions address a growing area of application within the railway sector.

Learn more about the project

FP4-RAIL4EARTH

The scope of FP4-Rail4Earth covers the sustainable and green rail system including rolling stock, infrastructure, stations, and their sub-systems.
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Europe's Rail