Analysis of different types of winter tyres in rear-end injury crashes and fatal loss-of-control crashes with ESC

Strandroth, Johan; Rizzi, Matteo; Ohlin, Maria; Eriksson, Jenny; Lie, Anders

Affiliations

¹Swedish Transport Administration, Sweden

²Chalmers University, Sweden

³Folksam Research, Sweden

⁴University of Gothenburg, Sweden

⁵Swedish National Road and Transport Research Institute, Sweden

Abstract

This study aimed to compare studded and non-studded winter tyres with regard to the risk of being the striking car in rear-end injury crashes with passenger cars. A further aim was to evaluate the risk for a passenger car equipped with Electronic Stability Control (ESC) to be involved in a fatal loss-of-control (LOC) crash with studded and non-studded winter tyres. This research was based on two different materials. The study on rear-end crashes used police reports from crashes in Sweden between 2008 and 2014. The study was limited to crashes occurring in the winter period, in this study defined as October through to March. Only car-to-car two vehicle crashes were included (n=4239). As tyre information was not included in the police reports, a survey form was sent to all drivers asking which type of tyres was fitted on their car at the time of the crash. In total, 717 drivers (17%) responded. The relative risk for being the striking or struck vehicle, depending on winter tyres, was calculated using an induced exposure approach. The analysis of fatal crashes in the winter period used in-depth studies of fatal crashes collected by the Swedish and Norwegian Transport Administrations in the winter period between 2003 and 2014. Cars fitted with ESC (n=44) were compared with cars without ESC (n=260). The odds ratio for being involved in a LOC-crash was calculated depending on the ESC fitment and fitment of different winter tyres. The findings showed that the risk for being the striking vehicle in a rear-end injury crash on ice or snow was at least 27% higher for non-studded winter tyres, compared to studded tyres. With regard to all road conditions, no significant difference between winter tyres with or without studs were found. As the proportion of ice and snow differs greatly in different parts of Sweden, the overall estimated effect was significant in northern Sweden but not in mid or southern Sweden. The risk of a fatal LOC-crash was 65% lower with studded tyres compared with non-studded winter tyres for cars without ESC. In ESC cars, the risk reduction, compared to cars without ESC, was 92% including all types of winter tyres, which were grouped together due to the limited size of the material. The rear-end crash analysis was based on a material with a rather limited response frequency. Hence, the representativeness of the results should be treated with caution. Regarding the fatal crashes it could be concluded that ESC is very effective in reducing LOC-crashes regardless of type of winter tyres. This is the first study that shows the effect of studded tyres related to specific crash types and to different geographical regions in Sweden. Hence, the findings in this study can contribute to the ongoing discussion on reducing the proportion of studded tyres in Sweden due to environmental and health issues

Links

URL: http://www-esv.nhtsa.dot.gov/Proceedings/24/files/24ESV-000368.PDF

Cited Works (1)

Year	Entry
2005	Lie A, Tingvall C, Krafft M, Kullgren A. The effectiveness of ESC (electronic stability control) in reducing real life crashes and injuries. In: Proceedings of the 19th International Technical Conference on the Enhanced Safety of Vehicles (ESV). June 6-9, 2005; Washington, DC.

Cited By (1)

Year	Entry
2017	Rizzi M, Kullgren A, Strandroth J, Ydenius A. Does all-wheel-drive (AWD) on passenger cars have any safety benefits on roads covered with ice or snow? analysis of real-world crashes involving awd cars with ESC (electronic stability control). In: Proceedings of the 25th International Technical Conference on the Enhanced Safety of Vehicles (ESV). June 5-8, 2017; Detroit, MI.