A comparison of headway and time to collision as safety indicators
2003 (English)In: Accident Analysis and Prevention, ISSN 0001-4575, Vol. 35, no 3, 427-433 p.Article in journal (Refereed) Published
The two safety indicators "headway" and "time to collision (TTC)" are discussed and compared with respect to their usefulness in determining the safety of different traffic situations, like different locations in a junction. Over a 6-day-period traffic flow measures were taken in a four-way junction with stop signs on the minor road. It was found that for vehicles in a car following situation headway and TTC are independent of each other. The percentage of small headways is relatively constant across different locations in the junction, while the percentage of small TTC values varies between different locations. It is recommended to use headway for enforcement purposes, because small headways generate potentially dangerous situations. TTC, on the other hand, should be used when a certain traffic environment is to be evaluated in terms of safety, because it indicates the actual occurrences of dangerous situations. (C) 2002 Elsevier Science Ltd. All rights reserved.
Place, publisher, year, edition, pages
2003. Vol. 35, no 3, 427-433 p.
safety assessment, safety indicator, time to collision, headway
IdentifiersURN: urn:nbn:se:liu:diva-48663OAI: oai:DiVA.org:liu-48663DiVA: diva2:269559