Systemic Safety Programs

A common approach to managing road safety is to identify and correct locations based on a large number of expected crashes occurring. While this is a valid and logical approach, it may fail to identify safety issues that are geographically widespread across the road network. For example, pedestrian crashes are relatively rare compared to most crash types, and hotspots with many such crashes rarely emerge.

A Systemic Safety Program aims to select and treat locations, not based on crash history, but based on site-specific geometric and operational attributes known to increase crash risk. Systemic Safety Programs focus on treating all those locations where crash risk is identified to be higher even if crashes have yet to be observed. With such a wide focus, treatments undertaken are typically lower cost. For example, many cities have made a decision to install leading pedestrian interval signal timing at all signalized intersections to improve pedestrian safety.

A Systemic Safety Program has a 4-step process:

1. Identify focus crash types and risk factors
2. Screen and prioritize candidate locations
3. Select countermeasures
4. Prioritize projects

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Systemic safety approaches can be used in conjunction with traditional hotspot programs to ensure it is not just highly concentrated crash types and locations being treated. Some jurisdictions have learned that after treating their worst performing locations, no more hotspots remain and have moved entirely towards a systematic approach.

A systemic approach is most relevant to rarer, dispersed crash types that can benefit from lower cost treatments, such as:

• Lane departure
• Rollover
• Head-on
• Impaired driving
• Vehicle-pedestrian
• Vehicle-bicycle

Examples of treatments amenable to a systemic approach include:

• Rumble strips (both shoulder and centerline)
• Cable median barrier
• High friction surface treatments
• Curve warning signs
• Signal backplates
• Countdown pedestrian signals
• Educational campaigns

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The identification of focus crash and location types involves identifying risk factors by analyzing crash data. In the absence of data, a review of previous research studies can identify focus areas to consider.

Methodologies to support a Systemic Safety Program can include simple frequency graphs and cross-tabulations, crash tree diagrams or more sophisticated approaches applying statistics. A discussion of these methods is available in Emphasis Areas.

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A Systemic Safety Program is typically led by the transportation department or whichever organization is responsible for road safety projects.

The identification of focus crash and location types typically includes agencies addressing the components within a Safe System Approach. Examples of agencies at the local level that may be represented include:

• Transportation or highway agencies: operations, planning, design, road construction, maintenance.
• Law enforcement agencies: driver and vehicle safety surveillance.
• Health agencies: injury prevention, emergency medical care, alcohol and drug safety programs.
• Education agencies: driver education and through high school safety education.

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The minimum data requirements include crash data identifying the location type where the crash occurred at the network level. Crashes do not need to be linked to individual locations. If other data are available for specific locations and these can be linked to the crash data, then a more refined identification of risk factors can be done. If existing road and intersection data are limited, then video logs, aerial imagery, or field visits might supply useful information.

Further discussion of relevant data is available in Emphasis Areas.

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Identifying the risk factors to target requires people with a knowledge of how relevant data are collected and their limitations. When various datasets are being merged and/or queried, people with this skillset are needed, such as data scientists or other professionals with relevant experience. People with knowledge of statistical analysis of data should also be involved.

Additionally, these decisions are also subject to pragmatic and political considerations, so people with an understanding of how the safety program fits into the jurisdiction’s overall goals and policies should also be involved.

If an agency lacks the data or expertise to determine risk factors for the focus crash type, they may search for related results from research reports. For example, National Cooperative Highway Research Program Report 500 identifies risk factors related to specific crash types.

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There are several tools available to assist agencies in implementing a Systemic Safety Program.

1. Systemic Safety Project Selection Tool
   The Systemic Safety Project Selection Tool presents a process for incorporating systemic safety planning into traditional safety management processes. The Systemic Tool provides a step-by-step process for conducting systemic safety analysis; considerations for determining a reasonable distribution between the implementation of spot safety improvements and systemic safety improvements; and a mechanism for quantifying the benefits of safety improvements implemented through a systemic approach. The tool is intended for use by transportation safety practitioners in state, county, and local government agencies to plan, implement, and evaluate systemic safety improvement programs and projects that best meet their capabilities and needs.
2. Systemic Safety Project Selection Tool Supplemental Case Studies
   This supplement to the Systemic Safety Project Selection Tool provides two additional case studies demonstrating the systemic analysis process. One case study demonstrates how State, county, and local government agencies in Minnesota evaluated pedestrian and bicycle safety issues in urban areas and developed a program to address these issues based on risk. The second case study illustrates how North Dakota conducted a systemic analysis with little supporting data initially available for analysis.
3. FHWA Website on Systemic Approach to Safety
   This source discuss what systemic approaches are, identified training opportunities and provides further sources.
4. Reliability of Safety Management Methods: Systemic Safety ProgramsThe Reliability of Safety Management Methods: Systemic Safety Programs guide describes the state-of-the-practice and the latest tools to support systemic safety analysis. The target audience includes program managers, project managers, and data analysts involved in projects that impact highway safety. The objectives of this guide are to: 1) raise awareness of the systemic approach to safety management, 2) characterize typical projects identified and implemented through a comprehensive safety management program, 3) demonstrate the value of integrating systemic approaches as part of a comprehensive safety management program, and 4) provide information on allocating funding to systemic projects within a comprehensive safety management program.

   This guide includes six sections and an appendix. The first section introduces roadway safety management and the purpose of safety programs. The second section provides an overview of two general approaches that support a comprehensive safety program, including a discussion of the high-level strengths and limitations. The third section demonstrates the value of projects implemented through various safety programs. Empirical examples lead to cost-effectiveness estimates and information on integrating the systemic approach within a comprehensive safety program. The next sections summarize the data requirements to employ, and available tools and resources to support, a comprehensive approach to safety management. The final section describes future research needs to enhance the state of the knowledge on the systemic approach. An appendix provides detailed information related to the methods and examples presented throughout the guide.

5. NCHRP Report 893: Systemic Pedestrian Safety Analysis
   This guidebook provides a framework for transportation agencies to take the steps needed to advance toward implementing a risk-based, systemic pedestrian safety management process. It is intended to serve state departments of transportation (DOTs) personnel and contractors, including managers and staff in highway safety improvement programs, pedestrian and bicycle programs, and safety data management programs. Its guidance is also applicable for local and regional transportation agencies that may be working independently or in coordination with state DOT staff on safety improvement efforts. The introductory chapter is intended for higher-level decision makers and elected officials. The objectives are providing a rationale and motivation for taking a systemic approach, clarifying key terms and definitions, describing the data needs for a systemic process and offering guidance on how agencies can acquire necessary data and conduct a systemic analysis. The guidebook also provides alternative methods and troubleshooting as well as highlights real-world examples that can provide motivation and models for systemic approaches.
6. NCHRP Report 955: Guide for Quantitative Approaches to Systemic Safety Analysis.NCHRP Research Report 955 provides guidance to state departments of transportation (DOTs) and other transportation agencies on how to apply a systemic safety management approach for identifying safety improvement projects. The report focuses on crash types that occur with high frequency across the roadway network but are not concentrated at individual locations, which tend to be overlooked when ranking sites using a traditional crash-history-based safety management approach. The guide and training materials will be of immediate use to safety practitioners in state DOTs, Metropolitan Planning Organizations, and local agencies.

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