Speed Variation Analysis – A Case Study for Thailand’s Streets and Roads

This report highlights the centrality of speed management to the Safe System approach and demonstrates how a simple speed variation can dramatically influence the safety of road users. At the core of this report lays the experience from the International Road Assessment Programme (iRAP) assessments undertaken between 2015 and 2019 on 867 km of national roads in Thailand and 258 km of streets in Bangkok, together with capacity building activities with local partner, Chulalongkorn University, which led to almost 700 specialists being trained on road safety engineering during this period. The importance of speed in influencing road user risk is highlighted in two case studies on different road types in Thailand — the Outer Ring Road and Hathai Rat Road in Bangkok — to demonstrate the effects of different speeds on the iRAP Star Ratings. These ratings objectively quantify the likelihood of a crash, and its severity, whereby a person’s risk of injury is highest on a 1-star road, and lowest on a 5-star road. Among a series of simulations and results, this report shows that enforcing a 10 kph speed limit reduction could prevent one in three fatal and serious injuries (FSIs) on both those roads.


  • English

Media Info

  • Media Type: Digital/other
  • Features: Figures; Maps; Photos; References; Tables;
  • Pagination: 30p

Subject/Index Terms

Filing Info

  • Accession Number: 01743625
  • Record Type: Publication
  • Files: TRIS
  • Created Date: Jun 10 2020 4:15PM