Tram to Pedestrian Collisions—Priorities and Potentials

Abstract

To improve mobility in cities in line with environmental goals, in urban traffic, trams represent an increasingly important means of transport. Due to the close interaction with other road users, this makes collisions with trams fairly frequent. This study has investigated accidents between trams and vulnerable road users resulting in personal injury, aimed at identifying priorities for simulating collisions between trams and pedestrians to assess passive safety measures. Tram accident data collection established throughout Europe from multiple sources and with varying degree of details, have been combined and analysed. These analyses comprise risk assessments per km-driven and general tram accident partner and site type evaluations, with more detailed analyses on accident site distance to the closest tram stop and injured body regions, respectively. In total, 7,535 tram-pedestrian accident resulting in 8,802 pedestrian injuries, collected in the year 2000–2021, was analysed. Accident risk ranges from 0.934 accidents per number of tram (million) km-driven, for slight injuries to 0.063 for fatal injuries. Pedestrians represent a large proportion of tram accident collision partners, especially for severe and fatal accidents. In accidents between trams and pedestrians, 3% of reported injuries are fatal, 23% severe and 74% minor. Generally, low-speed accidents close to tram stops often leading to minor injuries were observed to be of significant importance (<20m to the GPS location of a stop). Analysis of accidents was done bases on gender of the pedestrian showing overall similar involvements in accident with slight difference for various age groups and sites. Regardless of injury severity, the most frequently injured body region in accidents involving a tram is the head. Likewise, injuries sustained to the thorax, especially for higher injury severities are of high relevance, followed by injuries to the lower extremities. Based on this study, recommendations for developing reasonable tram-pedestrian accident scenarios for virtual testing can be derived for further optimisation of pedestrian safety of trams.

Assessment of Pedestrians’ Head and Lower Limb Injuries in Tram–Pedestrian Collisions

“…According to the reports from Swedish emergency hospital departments, femur and tibia fractures were the main form of lower limb injury for pedestrians in tram crashes [5], which is consistent with the findings of this paper. Additionally, Christine et al's study [17] identified instances where tibial accelerations surpassed safety thresholds, consistently exceeding femoral accelerations overall.…”

“…In particular, in the collision scenario with α = −90 • , there was not only the highest risk of brain contusion but also a high risk of facial bone fracture (including nasal and maxillary fractures) due to the direct action of the impact force on the face. This is also reflected in accident statistics, which show that 57 out of 554 tram-pedestrian collisions in Sweden between 2000 and 2021 involved facial fractures [5].…”

“…The growing tram network means that trams interact more frequently with other users, particularly pedestrians who are more vulnerable in traffic situations [4]. According to an analysis of accident statistics, a total of 7535 tram-pedestrian collision crashes occurred in Australia, Sweden, Switzerland, and Germany between 2000 and 2021, resulting in 8802 injuries or fatalities [5]. Based on 259 accident reports between 2000 and 2021 from Swedish emergency hospital departments, injuries to pedestrians in tram collisions were mainly represented by cerebrum injuries, cerebellum injuries, skull fractures, thorax internal organ injuries, rip fractures, pelvic fractures, femur fractures, and tibia fractures [5].…”

“…According to an analysis of accident statistics, a total of 7535 tram-pedestrian collision crashes occurred in Australia, Sweden, Switzerland, and Germany between 2000 and 2021, resulting in 8802 injuries or fatalities [5]. Based on 259 accident reports between 2000 and 2021 from Swedish emergency hospital departments, injuries to pedestrians in tram collisions were mainly represented by cerebrum injuries, cerebellum injuries, skull fractures, thorax internal organ injuries, rip fractures, pelvic fractures, femur fractures, and tibia fractures [5]. Pedestrians face a higher risk of death when involved in tram collisions compared with automobile collisions at the same speed.…”

“…Additionally, the lower extremities, which are the main initial point of contact in collisions, often receive severe injuries, mostly in the form of knee dislocations, femur fractures, tibia fractures, etc. [5,8,9].…”