Road Safety Manual
A manual for practitioners and decision makers
on implementing safe system infrastructure

You are here

9.4 Management Tools

A variety of tools and approaches are available to assist in the delivery of infrastructure safety management. As with guidelines, some tools have been prepared for use at the global, regional or country level. In some cases, the tools developed in one location or country can be adapted for use in another, but extreme care needs to be taken to ensure that the new context is considered when doing this. The types of tools available for road safety infrastructure management are mentioned in brief here, with further details provided in other relevant sections of this manual.

Schermers et al. (2011) provides a useful summary of tools used in Europe (most of which are discussed in this document. Elvik (2011) suggests a framework for applying tools that are related to the stages of a road’s life cycle. The US has also developed a comprehensive suite of tools for road safety infrastructure management. These are briefly discussed in the example in Box 9.7

Box 9.7: Safety Analyst, USA

The Safety Analytical Tools developed in the United States include:

The Network Screening Tool identifies sites with potential for safety improvements through algorithms that identify areas of concern (e.g. higher than expected crash frequencies). In addition, high crash severities or a higher than expected rate of specific collision types can also be identified. These algorithms are effective for spot locations, as well as short and extended road segments.

The Diagnosis Tool identifies the nature of safety problems at specific sites. It is able to generate a range of data, including crash summary statistics, collision diagrams, collision pattern identification (including whether or not a collision type occurs at a higher than expected rate), and to conduct statistical tests for specific sites. Both engineering and human factors are integrated to identify safety concerns.

The Countermeasure Selection Tool helps in the selection of interventions to reduce crash frequency and severity at sites. This tool incorporates site-specific countermeasures that are recommended based on the site type, crash patterns, and specific safety concerns identified with the earlier Diagnosis Tool. Single or multiple countermeasures may be selected and appraised with the Economic Appraisal and Priority Ranking tools.

The Economic Appraisal Tool performs an appraisal of either specific countermeasures or different options at a site. Within this tool, a number of economic evaluations can be undertaken, including cost-effectiveness, benefit-cost ratio and net benefits. Safety-effectiveness is estimated via observed, expected and predicted crash frequency and crash severity, as well as crash patterns and expected crash reduction for specific countermeasures. Notably, the analysis results are consistent with requirements of the Federal Highway Safety Improvement Programme guidelines.

The Priority Ranking Tool ranks sites and proposed improvements according to the benefit and cost analysis conducted by the Economic Appraisal tool. The site and improvement rankings are determined through comparison of cost-effectiveness, benefit-cost ratio, net benefits, safety benefits, construction cost, number of total crashes reduced, fatal and severe injury crash reduction, and fatal and all injury crash reduction. The Priority Ranking Tool assists in the optimisation of projects and maximisation of benefits across sites.

The Countermeasure Evaluation Tool allows pre- and post-evaluations of safety improvements using the Empirical Bayes (EB) approach. In addition, this tool has the capability to evaluate changes in the proportion of collision types. Analyses can also be performed to evaluate the efficacy of individual or combined countermeasures and construction projects. A benefit-cost analysis is also available to assess the economic benefits of countermeasures or construction projects.

Further details on these tools can be found at: http://www.safetyanalyst.org/.

 

The tools identified in Box 9.7 follow the broad stages of infrastructure safety management identified in Introduction. Later chapters discuss each of the key tools. The tools referenced for different stages of road safety management include:

  • Assessment of potential risk: A variety of tools exist to assist in the collection and analysis of crash and non-crash road safety data to assist in this task.

— Crash data: Establishing and Maintaining Crash Data Systems. discusses the establishment and use of crash data systems, and some of the useful tools that are desirable for such systems.

— Non-crash data: Non-Crash Data and Recording Systems. discusses non-crash data, including the need for systems to collect and analyse such information.

  • Identifying issues: Traditionally, tools for the assessment of risk have been reactive, as they were based on a concentration of crashes over time. In recent years, more proactive tools have been developed to identify risk locations. Both reactive and proactive tools are required to provide a full assessment of risk. Tools and approaches include:

— crash-based identification (Crash-based Indentification (‘Reactive Approaches’))

— road safety impact assessment (Road Safety Impact Assessment in Proactive Identification)

— road safety audit (Road Safety Audit in Proactive Identification)

— road safety inspection (Road Safety Inspection in Proactive Identification)

— road assessment programmes (Road Assessment for Safety Infrastructure in Proactive Identification).

  • Intervention selection: A variety of tools are available to help in the selection of appropriate interventions to address road safety risk. These include various websites that provide information on possible treatments based on problems identified. Intervention Selection And Prioritisation discusses some of the tools that can be used to assist in the selection of these treatments.
  • Prioritisation: Prioritisation tools exist to help conduct economic appraisals of different options at a location, or for different locations, and then to prioritise projects to help achieve the greatest benefits based on available budgets. This prioritisation process, as well as some of the tools that are available, are discussed in Priority Ranking Methods and Economic Assessments.
  • Monitoring and evaluation: Monitoring and evaluation is an essential part of infrastructure safety management. A limited number of tools are available to assist in this task, including the Countermeasure Evaluation Tool as part of the Safety Analyst suite discussed above. Further details on the importance of monitoring and evaluation can be found in Monitoring and Evaluation of Road Safety.

 

A further example, this one from France can be seen in Box 9.8.

Box 9.8: Road safety approaches for infrastructure, National Road Network, France

Since the early 2000s, France has developed and implemented a set of road safety approaches for infrastructure projects. This set of approaches is now outlined in the European Directive 2008/96 on road safety infrastructure management for French implementation projects.

A Road Safety Impact Assessment is carried out for all infrastructure projects at the initial planning stage before the infrastructure project is approved. It identifies the road safety considerations which contribute to the selection of the proposed solution and provides all relevant information necessary for a cost-benefit analysis of the different options assessed.

A Road Safety Audit of the design characteristics from a safety viewpoint is carried out for all infrastructure projects by a trained auditor or a team of auditors. Audits form an integral part of the design process of the infrastructure project and are carried out at different stages of the project: draft and detailed design, pre-opening and early operation. Where unsafe features are identified in the course of the audit, the design is rectified. When it is not rectified before the end of the appropriate stage, the reasons are stated by the authority in an annex of the report.

Source: Road Safety Audits (Sétra , 2012)

A Road Safety Inspection is carried out on the national road network for all existing roads in order to report on the details of the road, its surrounding area and the general environment that can influence the user’s behaviour or affect their passive safety and thus have repercussions on road safety. The concept is to provide a method that will help the operator to improve their network knowledge. Inspection visits are made by appropriately qualified personnel, to identify the main road safety issues, and to provide a fresh point of view on the system. The systematic inspection of a section of road thus consists of a quick and practical rating of the main configurations that may not be expected by the road user, considering all modes of transport.

Source: ISRI Initiative:  road safety inspections of routes (Sétra, 2008).

Safety of users on existing roads: this approach, called SURE in France, is carried out on the national road network for all existing roads. It is a general method of which the main innovation is to explicitly and continuously provide a complete approach of road safety improvements, from the road safety issues study to the assessment stage via the implementation of treatments. The aim of this approach is to determine and implement adapted treatments for sections of road where the safety gain is potentially higher.

The SURE process is a practical application of the common road safety approach presented in Examples of Infrastructure Policies, Standards and Guidelines in Policies, Standarts and Guidelines

  • Know: an issues study is conducted on a network divided into sections of road in order to establish a hierarchy of these sections compared to the potential safety gains;
  • Understand: a safety diagnosis and a set of treatments’ concepts are established for each selected section;
  • Take action: among those treatments’ concepts, a number of treatments are chosen and the road operator undertakes the planning, development and realisation of those treatments;
  • Assess: the treatments’ assessment and the monitoring of crashes on the selected road section and its zone of influence are realised.

Sources:

  • The SURE initiative (Users safety on existing roads) : Presentation and management (Sétra, France, 2006)
  • The SURE initiative (Users safety on existing roads) : Review of road safety issues for prioritizing routes (Sétra, France, 2006)
  • The SURE initiative (Users safety on existing roads) : Route diagnosis and options for action (Sétra, France, 2006)
  • The SURE initiative (Users safety on existing roads) : Action plan and implementation (Sétra, France, 2006)

 

All of these tools can (and should) be used in parallel. Each is useful for different purposes, and for different stages of infrastructure safety management. Strengths and weaknesses are discussed in later chapters. Historically, the collection and analysis of crash data has been the most widely applied approach to managing safety. This is likely to continue to be an important approach, and is an important starting point for those in LMICs. Road safety audit and safety inspection are other widely applied tools, including in LMICs. One added advantage of these approaches is that they are a useful mechanism to improve safety culture.

One often over-looked issue is that the earlier within the safety management process, or project development process, the greater the potential to make a cost-effective improvement in safety outcomes. This is best demonstrated in the planning and development phase. In many countries road safety practitioners have historically relied upon road safety audit to determine safety issues in planning and development stages of design. In more recent times, tools to assist in embedding safety into design at the earliest stages have been developed. Importantly, some of these are aimed at practitioners who are not from a safety background in an attempt to include safety considerations into decision-making. These tools can be either quantitative in approach (such as tools that are based on crash prediction models) or qualitative. One of the most widely applied quantitative models is the US Interactive Highway Safety Design Model (IHSDM). This includes several modules, some of which can be used at the project development stage (AASHTO, 2010). It should be noted that this tool is generally applied to existing roads in the US, as very few new roads are built. Further information on IHSDM can be found in Box 9.10 and in Proactive Identification.

iRAP has also been used to quantify safety implications at the early design stage (see the case study in Box 9.9).

Box 9.9: Case Study – Assessment and improvement of design plans – Moldova and India

The problem: New road designs are still being produced that result in significant numbers of deaths and serious injuries.

The solution: The iRAP star rating has been used in a number of countries to help improve design in order to achieve better safety outcomes. Examples include a pilot project in Moldova (the M2-R7 corridor – 116 km) and in India on the Karnataka State Highway Improvement Project (550 km). The projects were supported by the Millennium Challenge Corporation and the Global Road Safety Facility, respectively, as well as local and international partners.

Information was drawn from the road design plans prior to construction or rehabilitation to rate the safety of the proposed design. The iRAP star ratings score how road infrastructure influences the likelihood of crashes occurring and the severity of the crashes that do occur. The approach provides a simple and objective measure of the relative level of risk associated with road infrastructure for the movements and manoeuvres that road users make. Different design options are compared, and the likely safety outcomes of different designs determined.

The outcome: The roads in Moldova and India show substantial improvements in safety based on the final designs implemented, notably for pedestrians in villages. Final designs for construction are anticipated to provide a reduction in severe injuries of 40% per year in Moldova and 45% in India. On the larger, busier, Indian network, this approximates to saving more than 100 deaths per year.

A fuller account of the project in India is available in Rogers et al., 2012.

The road assessment identified the need for pedestrian facilities and improved pedestrian safety. Following the assessment, provision for pedestrians was added to the design (including crossings, median refuge islands and sidewalks) and measures were included to slow traffic.

Source: Case study provided by iRAP

 

Box 9.10: Case Study – Interactive Highway Safety Design Model (IHSDM)

The problem: Idaho Transportation Department (ITD) identified deficiencies on Idaho State Highway 8 related to traffic operations, road geometry, access control and safety. Idaho State Highway 8 is an 11-mile two-lane highway traversing through rural residential and agricultural land uses. ITD wanted to conduct a corridor study to assess the existing traffic conditions, geometry, and to predict future crashes.

The solution: ITD used the Federal Highway Administration (FHWA) IHSDM software for this study. The IHSDM software is a package of analysis tools to evaluate the safety and operation of geometric design decisions on highways, and predict crashes based on the AASHTO Highway Safety Manual methodologies. The advantage of using the IHSDM provided the opportunity to perform a detailed review within the corridor on a number of critical elements at the same time (i.e. traffic operations, geometry and safety) to identify and target potential problem areas and develop effective mitigation strategies. Data requirements included crash data, existing roadway design plans, video, traffic control information, and traffic volumes (existing and projected). Information on expected crash reduction was used to compare effects of alternative treatment options. The list of mitigation strategies developed to address the identified issues was evaluated and prioritized.

Figure 9.1: Idaho State Highway 8 Corridor - Source: FHWA, 2015.

The outcome: From the IHSDM output, ITD found more than half of the 11-mile corridor experienced a crash rate higher than the statewide average. The IHSDM Policy Review and Crash Prediction modules resulted in identifying geometric deficiencies, specific locations requiring further investigation, areas that required design improvements and safety issues on the corridor. A Corridor Plan Report was prepared which summarised the review, analysis and recommendations to be considered for potential improvement projects and programmed for implementation by the ITD over the next 10 years. Recommended mitigation measures consisted of passing lanes, intersection capacity improvements, sight distance improvements, roadside safety enhancements, intelligent transportation systems (ITS), animal crossings, and access management strategies.

Further information can be found on the FHWA website (http://safety.fhwa.dot.gov/hsm/casestudies/id_cstd.pdf).

Source: FHWA, 2015.

 

The Strategic Tool for Assessment of Road Safety (STARS), developed in Australia, relies on checklists to help identify negative safety outcomes (Jurewicz, 2009). This approach provides a risk value to each of the checklist questions, and ultimately an overall safety rating for the planned project. Checklists are available for different stages of development, including regional or structure plans, master plans, sub-division or neighbourhood plans, arterial corridors, and new/commercial developments. Example road safety planning issues at the regional level include:

  • Maximising public transport usage and minimising personal vehicle use - entails assessing ease of access to public transport through checking the location of activity centres in relation to public transport hubs (e.g. interchanges or train stations). It also involves assessing the location of major employment destinations and mixed land use prioritised around activity centres.
  • Minimising traffic conflict along arterial roads - involves checking separation of arterial roads from residential areas and strip shopping centres, assessing whether the proposed plans support the control of vehicular access from arterial roads to adjacent lands and checking whether there is grade separation at level crossings.
  • Maximising safe pedestrian and cyclist travel - involves assessing whether there are adequate and up-to-date provisions for pedestrians and cyclists and whether on- and off road facilities are planned for.

Further information on safety assessment prior to a road safety audit can be found in Road Safety Impact Assessment in Proactive Identification.

Road safety management tools need constant review as good practice and new approaches emerge. Elvik (2011) conducted such a review of European infrastructure safety management tools, and despite the many years of development and experience in using such tools, a number of opportunities for improvement were identified. Some of the key findings were that:

  • There is a need to evaluate the effect on safety of road safety audit, safety inspection and road protection scoring, including the ability of these tools to identify safety solutions.
  • The techniques adopted in the US Safety Analyst tool (see Box 9.7) for network screening should be used in Europe, and crash models should be used.
  • The Empirical Bayes approach should be used in the selection of high risk locations (see Identifying Crash Locations in Crash-based Indentification (‘Reactive Approaches’)).

Pathway to Effective Infrastructure Safety Management, Policies, Standards and Guidelines

Getting started

  • A good understanding of infrastructure safety principles based on Safe System is required by key agency staff and stakeholders – from senior management through to technical staff.
  • Review and internationally benchmark selected infrastructure safety policies and interventions, and commence implementation of reforms.
  • Ensure safety is linked to broader transport policy, and safety is embedded within this policy.
  • Assess the safety of high volume, high risk locations (e.g. high crash density demonstration corridors and urban areas) and implement multi-sector improvement programmes.
  • Adopt tools for the management of road safety, and train key staff in the use of such tools.

Making progress

  • Ensure all road agency staff have a good understanding of infrastructure safety principles based on Safe System principles. All staff, from senior management through to technical staff need this understanding, regardless of whether safety is the main focus of their role. This includes staff responsible for national, regional and local roads.
  • Ensure that other stakeholders have good knowledge of infrastructure safety principles based on the Safe System approach.
  • Implement ongoing reforms of safety policies and interventions, and introduce new measures in accordance with international good practice.
  • Roll-out multi-sectoral measures (i.e. those that integrate infrastructure measures with e.g. enforcement, education, and post-crash care improvements), including across high risk corridors and urban areas.
  • Continue to develop and tailor road safety tools, and ensure road agency staff and other stakeholders are adequately trained in the use of these tools.

Consolidating activity

  • Continue to develop the understanding of infrastructure safety based on Safe System principles amongst all agency staff, stakeholders and members of the public.
  • Review and internationally benchmark safety policies and interventions, and implement reforms.
  • Sustain comprehensive multi-sectoral measures across the whole road network and extend targeting to less risky roads.
  • Continually improve road safety tools, and maintain high level of training and use amongst all stakeholders.

 

Reference sources

No reference sources found.