PARTICULATES Characterisation of Exhaust Particulate Emissions from Road Vehicles Deliverable 8 Measurement of non-exhaust particulate matter Version 2.0 – October 2004 A project sponsored by: EUROPEAN COMMISSION Directorate General Transport and Environment In the framework of: Fifth Framework Programme Competitive and Sustainable Growth Sustainable Mobility and Intermodality Contractors LAT/AUTh: Aristotle University of Thessaloniki, Laboratory of Applied Thermodynamics - EL CONCAWE: CONCAWE, the oil companies' European organisation for environment, health and safety - B VOLVO: AB Volvo - S AVL: AVL List GmbH - A EMPA: Swiss Federal Laboratories for Material Testing and Research - CH MTC: MTC AB - S TUT: Tampere University of Technology - FIN TUG: Institute for Internal Combustion Engines and Thermodynamics, Technical University Graz - A IFP: Institut Français du Pétrole - F AEA: AEA Technology plc - UK JRC: European Commission – Joint Research Centre - NL REGIENOV: REGIENOV - RENAULT Recherche Innovation - F INRETS: Institut National de Recherche sur les Transports et leur Securité - F DEKATI: DEKATI Oy - FIN SU: Department of Analytical Chemistry, Stockholm University - S DHEUAMS: Department of Hygiene and Epidemiology, University of Athens Medical School - EL INERIS: Institut National de l’ Environnement Industriel et des Risques - F LWA: Les White Associates - UK TRL: Transport Research Laboratory - UK VKA: Institute for Internal Combustion Engines, Aachen University of Technology – D VTT VTT Energy – Engine Technology and Energy in Transportation - FI A project sponsored by: EUROPEAN COMMISSION Directorate General Transport and Environment In the framework of: Fifth Framework Programme Competitive and Sustainable Growth Sustainable Mobility and Intermodality Publication data form 1. Framework Programme 2. Contract No European Commission – DG TrEn, 5th Framework 2000-RD.11091 Programme Competitive and Sustainable Growth Sustainable Mobility and Intermodality 3. Project Title 4. Coordinator Characterisation of Exhaust Particulate Emissions from Road LAT/AUTh Vehicles (PARTICULATES) 5. Deliverable Title 6. Deliverable No Measurement of non-exhaust particulate matter 8 (revised) 7. Deliverable Responsible 8. Language 9. Publication Date Dr Paul Boulter - TRL English October 2004 10. Author(s) 11. Affiliation Lakhu Luhana1, Ranjeet Sokhi1, Lynne Warner1, Hongjun Mao1, Paul 1 University of Hertfordshire, College Boulter2, Ian McCrae2, Julian Wright3 and Daniel Osborn3 Lane, Hatfield, Herts AL10 9AB, UK. 2 TRL Ltd, Crowthorne House, Nine Mile Ride, Wokingham, Berkshire, RG40 3GA, UK 3 CEH, Abbots Ripton, Huntingdon, Cambridgeshire PE28 2LS, UK 12. Summary This report presents the findings of work undertaken to characterise airborne particles emitted by road traffic, with the aim of deriving emission factors for non-exhaust particle sources such as tyre wear, brake wear and road surface wear. The report includes a literature review which examines the state of the art in this field, and describes the formulation of an optimum methodology for determining emission factors. Wear rates for brake pads and tyres have been determined gravimetrically for in-service cars. Sampling campaigns have been carried out to collect ambient particulate matter and source materials, including road dust, tyre material and brake wear particles. Ambient airborne particles, as well as the source materials, have been characterised chemically and physically using a suite of analytical techniques including ICP/AES, ICP/MS and SEM. Levels of PM10 and PM2.5 have been estimated from gravimetric measurements at roadside and background sites at the University of Hertfordshire and London. The information from these campaigns and the literature review has been used to identify specific tracers for apportioning the sources of non-exhaust particles, and has assisted in the design of a main tunnel sampling campaign to derive appropriate emission factors. The main campaign has been conducted in the Hatfield Tunnel on the A1(M) motorway north of London. Emission factors for light-duty and heavy-duty vehicles have been determined using principle component analysis and multiple regression analysis. 13. Notes 14. Internet reference 15. Key Words 16. Distribution statement Non-exhaust particles, emission factors, receptor FREE modelling, tyre wear, brake wear, road dust 17. No of Pages 18. Price 19. Declassification date 20. Bibliography 96 FREE NO Acknowledgements The authors would like to take this opportunity to thank the following for their help and advice during this project: • Westminster City Council, London, UK. • Ana Deletic and David Orr, Aberdeen University, UK. • Professor Dick van den Hout, TNO Institute of Environmental Sciences: Energy Research and Process Innovation, the Netherlands. • Dr Peter Schmid, EMPA, Dubendorf, Switzerland. • Dr Jay Turner, Washington University, St. Louis, Missouri, USA. • Ms Laurel Martin at the California Institute of Technology, Pasadena, California. • Claire Wienburg, CEH, UK. • Sarah James, Nick Walsh and Jacqui Duffett, Royal Holloway College, University of London, UK. • Carillion-URS plc, who operate the Hatfield Tunnel on behalf of the Highways Agency and, in particular, Mr Jeff Chappell the Hatfield Tunnel manager. Table of Contents 1 Introduction ......................................................................................................................................1 1.1 Background ...........................................................................................................................................1 1.2 Non-exhaust particle research in the PARTICULATES project ...............................................2 2 Review of non-exhaust particle research.................................................................................3 2.1 Atmospheric particulate matter........................................................................................................3 2.2 Tyre wear particles ..............................................................................................................................4 2.2.1 Factors affecting tyre wear.........................................................................................................4 2.2.2 Tyre wear rates............................................................................................................................5 2.2.3 Tyre composition .........................................................................................................................6 2.2.4 Tyre wear particle characteristics .............................................................................................7 2.3 Brake Wear particles ...........................................................................................................................9 2.3.1 Factors affecting brake wear .....................................................................................................9 2.3.2 Brake wear rates........................................................................................................................10 2.3.3 Brake composition.....................................................................................................................10 2.3.4 Brake wear particle characteristics.........................................................................................12 2.4 Clutch wear particles ........................................................................................................................13 2.5 Corrosion particles............................................................................................................................13 2.6 Road surface wear particles............................................................................................................14 2.7 Resuspension of Road Dust ...........................................................................................................16 2.7.1 Sources and composition.........................................................................................................16 2.7.2 Factors affecting resuspension ...............................................................................................17 2.7.3 Particle emission factors ..........................................................................................................18 2.8 Research methods.............................................................................................................................18 2.8.1 Methods for determining tyre wear and tyre particle emissions.........................................18 2.8.2 Methods for determining brake wear and particle emissions .............................................19 2.8.3 Methods for sampling road dust..............................................................................................19 2.8.4 Source apportionment methods: receptor modelling ...........................................................20 2.9 Summary of literature review..........................................................................................................23 2.9.1 Tyre wear particles....................................................................................................................23 2.9.2 Brake wear particles..................................................................................................................23 2.9.3 Clutch wear particles.................................................................................................................23