Guides

Part 3 of the Guide to Road Safety addresses Safe Speed — managing travel speeds so that the kinetic energy released in a crash stays within the limits the human body can tolerate. It explains the biomechanical thresholds that underpin Safe System speed limits and how speed interacts with road design, road function and the mix of road users to determine crash likelihood and severity.

This part provides guidance on setting and reviewing speed limits, aligning speed with the movement-and-place function of a road, and combining speed management with infrastructure and enforcement. It covers the process from strategic speed-management policy through to individual road-section speed-limit decisions, and the monitoring needed to confirm interventions are delivering the expected reduction in trauma.