{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,2,3]],"date-time":"2026-02-03T03:02:15Z","timestamp":1770087735859,"version":"3.49.0"},"reference-count":32,"publisher":"MDPI AG","issue":"2","license":[{"start":{"date-parts":[[2026,2,2]],"date-time":"2026-02-02T00:00:00Z","timestamp":1769990400000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"RCM2+ Research Centre in Asset Management and System Engineering"},{"name":"Forest Fire Research Laboratory (LEIF) of the Forest Fire Research Center (CEIF) of ADAI, University of Coimbra"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Vehicles"],"abstract":"<jats:p>Passenger transport companies have often been affected by fires in their vehicles, causing considerable damage. As a result, it is important to study the causes and effects of these fires, as well as to define the maintenance policies and strategies to be implemented to minimize the probability of this type of accident occurring. The support for this paper was based on the study of an accident that occurred in Portugal involving a passenger bus that suffered a fire in the engine compartment, which spread to the passenger compartment and caused the destruction of the vehicle, with no personal injuries. This study used infrared image analysis technology, oil ignition temperature analysis, maintenance history, accident history and operator interviews to determine the possible cause of the ignition. It was found that the cause was due to oil leaks from the engine compartment cooling system. The present communication will share a set of explanatory elements of the circumstances in which the accident occurred. In addition to identifying the causes of the accident, the study warns of the importance of more effective and efficient maintenance, particularly when using Condition Based Maintenance (CBM), including periodic visual inspections of the various mechanical and electrical components that make up the vehicles. The conclusions presented in the study also show that these events are not unrelated to the poor or even non-existent maintenance policy for the entire fleet, including the applicable standards.<\/jats:p>","DOI":"10.3390\/vehicles8020029","type":"journal-article","created":{"date-parts":[[2026,2,2]],"date-time":"2026-02-02T12:49:44Z","timestamp":1770036584000},"page":"29","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":0,"title":["Fires in Urban Passenger Transport Vehicles Engine\u2014Case Study"],"prefix":"10.3390","volume":"8","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-1682-5950","authenticated-orcid":false,"given":"Hugo","family":"Raposo","sequence":"first","affiliation":[{"name":"Polytechnic University of Coimbra, Rua da Miseric\u00f3rdia, Lagar dos Corti\u00e7os, S. Martinho do Bispo, 3045-093 Coimbra, Portugal"},{"name":"RCM<sup>2+<\/sup>\u2014Research Center for Management Engineering and Asset Systems, Polytechnic University of Coimbra, Rua Pedro Nunes-Quinta da Nora, 3030-199 Coimbra, Portugal"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-3964-9400","authenticated-orcid":false,"given":"Jorge","family":"Raposo","sequence":"additional","affiliation":[{"name":"Polytechnic University of Coimbra, Rua da Miseric\u00f3rdia, Lagar dos Corti\u00e7os, S. Martinho do Bispo, 3045-093 Coimbra, Portugal"},{"name":"RCM<sup>2+<\/sup>\u2014Research Center for Management Engineering and Asset Systems, Polytechnic University of Coimbra, Rua Pedro Nunes-Quinta da Nora, 3030-199 Coimbra, Portugal"},{"name":"FCNET\u2014Faculdade de Ci\u00eancias Naturais, Engenharias Tecnologias, Lus\u00f3fona University, 4000-098 Porto, Portugal"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-9694-8079","authenticated-orcid":false,"given":"Jos\u00e9 Torres","family":"Farinha","sequence":"additional","affiliation":[{"name":"Polytechnic University of Coimbra, Rua da Miseric\u00f3rdia, Lagar dos Corti\u00e7os, S. Martinho do Bispo, 3045-093 Coimbra, Portugal"},{"name":"RCM<sup>2+<\/sup>\u2014Research Center for Management Engineering and Asset Systems, Polytechnic University of Coimbra, Rua Pedro Nunes-Quinta da Nora, 3030-199 Coimbra, Portugal"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-9508-6510","authenticated-orcid":false,"given":"J. Edmundo","family":"de-Almeida-e-Pais","sequence":"additional","affiliation":[{"name":"Polytechnic University of Coimbra, Rua da Miseric\u00f3rdia, Lagar dos Corti\u00e7os, S. Martinho do Bispo, 3045-093 Coimbra, Portugal"},{"name":"RCM<sup>2+<\/sup>\u2014Research Center for Management Engineering and Asset Systems, Polytechnic University of Coimbra, Rua Pedro Nunes-Quinta da Nora, 3030-199 Coimbra, Portugal"},{"name":"CISE\u2014Electromechatronic Systems Research Centre, University of Beira Interior, 6201-001 Covilh\u00e3, Portugal"}]}],"member":"1968","published-online":{"date-parts":[[2026,2,2]]},"reference":[{"key":"ref_1","unstructured":"(2021). Maintenance\u2014Maintenance Terminology (Standard No. EN 13306:2021)."},{"key":"ref_2","doi-asserted-by":"crossref","unstructured":"Farinha, J.T. (2018). Asset Maintenance Engineering Methodologies, CRC Press. 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