Introduction

Purpose

This document:

  • Provides details of the process adopted and experience gleaned during Phase 1 (2020 to 2023) and Phase 2 (2023 to 2025) of PRIME traffic signs and markings road trials on the Scottish trunk road network.
  • May be of interest to road safety professionals responsible for instigating schemes improving the road environment for motorcyclists (i.e. vulnerable road users) to support safe journeys, in line with the ‘Safe System’ approach set out in Scotland’s Road Safety Framework to 2030.

This document is primarily aimed at those working in various areas of road safety such as road authorities, their supply chain, and road safety partnerships who may be interested in the use of PRIME measures on their road networks. It presents the practical outputs of Project PRIME Phase 1 to assist in considering replicating the design and implementation of the Scottish Trunk Road trials. 

Background

Project PRIME (Perceptual Rider Information for Maximisation of Enjoyment and Expertise) has undertaken pioneering, world-leading and award-winning research into new traffic signs and road markings for motorcyclists approaching bends. Funded by Transport Scotland and the Road Safety Trust it has helped to deliver the research and provide the scientific evidence base for installing PRIME measures.

During Phase 1 (2020 to 2022) PRIME road markings were installed as a series of ‘gateways’ on approach to a bend to encourage safer riding. They were installed at 22 bends on trunk roads in Scotland with either 50 mph or 60 mph speed limits. The results demonstrated improvements in rider behaviour in relation to speed, position and braking which are all key factors for safer riding. The findings also support the ‘Safe System’ approach to preventing and reducing motorcycle casualties. 

During Phase 2 (2023 to 2025) PRIME road markings were installed at an additional 13 bends with either 50 mph or 60 mph speed limits, plus 5 sites previously used in Phase 1. The results further demonstrated improvements in rider behaviour as well as evidence of carry over effects to subsequent bends and long term effects following installation.

Costs and benefits

PRIME measures offer a low-cost and low-maintenance road engineering intervention to improve rider behaviour. Although there is no legal requirement for motorcyclists to use the PRIME road markings, the research evidence demonstrates that PRIME measures are readily adopted by riders and could potentially to be incorporated into education initiatives for road safety and casualty reduction.

Once sites have been identified and designs have been completed, the PRIME traffic sign and road markings can be installed in a relatively short time (typically 1 to 2 hours) with minimal disruption to the road network and without the need for other road engineering or improvement works, although this might be considered as part of a wider scheme to implement PRIME measures. 

Impact

Project PRIME has received worldwide interest for motorcycle casualty reduction and underpins Transport Scotland’s current ‘Road Safety Framework to 2030′ with a desired 30% reduction in motorcycle KSIs within that timeframe.

 Project PRIME has been recognised in the following awards:

  • ‘Prince Michael International Road Safety Award’ 2023
  • Institute of Highways Engineers Highways Awards 2023 – ‘Road Safety Scheme of the Year’ and ‘Judges Special Merit Award’
  • Chartered Institution of Highways and Transportation Awards 2023 – ‘Road Safety Award’ (highly commended) and ‘Research Initiative of the Year’ (commended)

Detailed and rigorous scientific research underpins Project PRIME. This research has been peer-reviewed to the highest standards and published in leading international journals and at international conferences (see: Appendix A).

Using this document

This document draws together the processes followed in the research from Project PRIME for installing PRIMEs at specific sites for traffic driving on the left-hand side of the road and reflects legislation and practice in Scotland at the time of the trials.

This document presents key information in an accessible format that readers may wish to use in order to replicate installations but it does not constitute specific instructions to follow. 

The document should not be considered as an approved standard or best practice. It is also not an exhaustive description of every potential installation as it is likely PRIME measures will be installed in many different areas.

PRIME traffic signs and road markings are not currently prescribed in the Traffic Signs Regulations and General Directions 2016 (“TSRGD”). It is important that any organisation using PRIME traffic signs and road markings gains the appropriate authorisation before installing PRIME measures on their road network. Consideration may be needed of relevant legislation and procedures pertaining to intended installations. 

The information in this document is provided in good faith and is intended to provide information on the PRIME trials on Scottish Trunk Roads to practitioners in other organisations. Nevertheless, whoever uses the information contained herein does so at their own risk and needs to satisfy themselves that they are competent to do so and have met the requirements of their Overseeing Organisation and other relevant regulations. Neither Transport Scotland, The Road Safety Trust or any partners on Project PRIME will be liable for any loss or damage sustained by any person relying on this document, whatever the cause of such loss or damage.

In the following sections, this document provides details on:

  • PRIME site characteristics and behaviour change
  • PRIME site selection
  • PRIME design and installation
  • PRIME site monitoring and evaluation

Taken together, these points could help inform where and how PRIMEs might be installed for specific behavioural change, road safety and casualty reduction outcomes.

Feedback

We welcome any feedback on your experiences of using the information provided and installing PRIME measures in your area so that we can continue to make improvements to the presentation of the document in the future. Please contact: strategic_road_safety@gov.scot