T0637 Speed Management literature review

Description

Speed management is a critical aspect of road safety and forms one of the pillars of the Safe System approach.
This work directly supports the Road to Zero Harm project. Road to Zero Harm is an exciting and ambitious road safety initiative that we're championing to realise our vision, that no-one should be killed or seriously injured on our roads. The initial independent research, grounded in the Safe System approach, generated a comprehensive list of potential evidence-based safety measures. This list was then validated by experienced road safety practitioners. The Safe System considers how roads, vehicles, people, speeds, and post-collision care come together in the way we manage and improve safety. 
Workstream 5 of the road map relates specifically to speed. 'Optimise speed management on the SRN to align speeds to the road environment and the way the road is used'.
Our initial consultation with regional colleagues suggests that the main regional speed management challenges are:  
-	Responding to requests to lower the speed limit  
-	Reviewing limits in places where the speed limit does not 'feel right' for the road environment  
In May 2024 a speed management module was launched within the Route Review Tool to model a variety of speed related countermeasures to assess their expected impact on improving safety along routes. 
To better support the organisation in adopting a consistent approach to speed management we are seeking to develop a guiding set of principles within a speed management policy to support decision making across the business. This policy will cover managing speeds across the existing network which could include reducing speed limits or encouraging compliance with existing limits.
Variable speed limits on managed motorways and road works are out of scope for this policy.  These areas are covered by existing guidance.
To ensure this policy aligns with existing research and literature, National Highways are seeking a review of current speed management practice across the road industry. 
We are aware an international literature review has been undertaken by Transport for Scotland. We are keen to review this as a baseline for our literature review to build an evidence base to inform our approach.