About the Systemic Approach

How it Works

The Systemic Safety Project Selection Tool involves three basic elements: Element 1: Selecting locations and countermeasures; Element 2: Achieving the correct balance between systemic and traditional safety investments; and Element 3: Evaluating the effectiveness of the systemic approach.

Together, the traditional site analysis approach and the systemic approach form a comprehensive approach to safety management. Both approaches include the same basic planning elements of traditional roadway safety management processes, such as the Highway Safety Improvement Program (HSIP). An important distinction in the systemic approach is the decision-making process does not just identify the most appropriate countermeasure for each individual location, as done when addressing hot spots. The systemic approach considers multiple locations with similar risk characteristics, selecting a preferred countermeasure(s) appropriate and affordable for widespread implementation. That is why it is necessary to identify low cost solutions.

Click on the following planning steps to learn more about the steps involved in the systemic approach.

Purple Circle – Evaluation

Quantifying the effectiveness of systemic safety improvements is a critical aspect of systemic safety planning. Evaluating perfor¬mance is the last element of the Systemic Safety Project Selection Tool, and it provides useful feedback into the systemic safety planning process. The systemic safety evaluation process occurs at three levels:

  • Output: What is the output of the systemic safety program? Is the systemic safety program being implemented as planned and programmed? Are high priority countermeasures being deployed at the right type of locations and at the number of locations planned?
  • Focus Crash Type: Has implementation effectively reduced the identified focus crash types? That is, are the severe crashes trending down?
  • Countermeasure Performance: Within each crash type, are deployed counter-measures performing as expected?

The Systemic Safety Project Selection Tool provides a framework for evaluating systemic safety program effectiveness in each of these categories.

Conducting an evaluation of systemic safety projects provides the opportunity to refine a systemic safety program by directing subsequent funding to proven projects and countermeasures specific to your agency. Thus, you can maximize crash reduction by allocating funding where it will provide the greatest benefit toward reducing the frequency of severe focus crashes.

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Green Circle – Implementation

In the funding and implementation step of the Systemic Safety Project Selection Tool, a framework is provided for determining an appropriate balance between funding safety improvements at site specific locations or funding systemic improvements given particular crash and roadway system characteristics.

The framework recognizes there will be some balance between projects derived from the site analysis approach and those selected through a systemic approach. This balance between projects will likely vary based on different regions of a state (e.g., urban versus rural), on different components (e.g., state versus local), and for different focus crash types (e.g., rear end versus road departure crashes). In developing a funding balance, consider the following:

  • Many high-crash locations suggest directing more safety funds toward site analysis projects; few high-crash locations suggest directing more safety funds toward systemic safety projects.
  • A performance measure based on total crashes suggests a site analysis safety program; a performance measure based on severe crashes suggests a more systemic safety program.
  • An overrepresentation of crashes in urban areas suggests a site analysis safety program; an overrepresentation of rural crashes suggests a more systemic safety program might be appropriate.
  • A safety program focused on all crash types suggests a site analysis program; a focus on specific crash types suggests a more systemic program.
  • A focus on signalized intersections suggests a site analysis program; a focus on unsignalized intersections and horizontal curves suggests a more systemic focus.
  • A comprehensive safety management program will include both site analysis and systemic safety programs. Even if all “arrows” point toward a more systemic safety program, you must still address your high crash locations.

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Step 1 – Identify Target Crash Types and Risk Factors

Systemic problem identification involves identifying focus crash types and the commonly associated location characteristics experienced across a system. This is a system-wide or macro-level review of the crash data and documentation of crash characteristics. The tasks involved include the following:

Task 1 – Select the Focus Crash Types
Identify the categories of severe crashes that represent the greatest opportunities for reduction, which are usually those crash types that represent the greatest number of severe crashes across the system being analyzed. Click here for a Task 1 example.

Task 2 – Select Focus Facilities
Determine where or on what facilities the crashes are occurring. Click here for a Task 2 example.

Task 3 – Identify and Evaluate Risk Factors
Document and evaluate the most common characteristics or risk factors of the locations where crashes occurred. Click here for a Task 3 identification example; click here for Task 3 evaluation example.

Additional information is available on the Step and Tasks in the Systemic Safety Project Selection Tool, which will be available soon.

 

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Step 2 – Screen and Prioritize Candidate Locations

The objective of this step is to develop a prioritized list of potential locations on the roadway system (segments, curves, intersections, etc.) that could benefit from systemic safety improvement projects.

Task 1 – Identify Network Elements Analyzed
Identify the network elements from the focus facility types selected in Step 1, Task 2, which represent the locations where the target crash types tend to occur for use in network screening. Click here for an example of Task 1.

Task 2 – Conduct a Risk Assessment
Evaluate the risk factors of the systems and locations selected for analysis using roadway and traffic characteristics in order to rank/prioritize at-risk locations. Click here for an example of Task 2.

Task 3 – Prioritize Roadway Facilities
The prioritized lists of segments, horizontal curves, and intersections are generated based on the presence of the selected risk factors – the more risk factors present, the greater the potential for the focus crash type and the higher the priority as a candidate for safety investment. Click here for an example of Task 3.

Additional information is available on the Step and Tasks in the Systemic Safety Project Selection Tool, which will be available soon.

 

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Step 3 – Select Countermeasures

This step involves selecting a small number of low-cost, highly effective countermeasures to be considered for project development at candidate locations.

Task 1 – Assemble Comprehensive List
The first task involves assembling a comprehensive list of the safety countermeasures associated with each of the targeted crash types. Some of the resources available to help identify these countermeasures include the NCHRP Report 500 series, Highway Safety Manual, Crash Modification Factors (CMF) Clearinghouse, etc. Click here for an example of Task 1.

Task 2 – Evaluate/Screen Countermeasures
The second task is to evaluate and screen the initial list of countermeasures based on a documented effectiveness (at reducing the target crash types), implementation and maintenance costs, and consistency with the agency’s policies, practices, and experiences. Click here for an example of Task 2.

Task 3 –Select Countermeasures for Deployment
Identify countermeasures for each of the target crash types that comprise the short list of strategies that is used to develop safety projects at specific locations across an agency’s road system. Click here for an example of Task 3.

Additional information is available on the Step and Tasks in the Systemic Safety Project Selection Tool, which will be available soon.

 

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Step 4 – Prioritize Projects

The objective of this final step of the systemic safety project selection process is to identify/develop the list of high-priority safety improvement projects. This list of projects considers the prioritized at-risk locations identified in Step 2 and applies the most appropriate countermeasures from the list selected in Step 3.

Task 1 – Create a Decision Process for Countermeasure Selection
This task involves the creation of a decision-making process that includes the set of criteria such as volume, environment, adjacent land use, or cross section that will be used to identify the appropriate countermeasure for high-priority locations. The decision making process in the systemic approach does not just identify the most appropriate countermeasure for each individual location, as done when addressing hot spots. The systemic approach considers multiple locations with similar risk characteristics, selecting a preferred countermeasure(s) appropriate and affordable for widespread implementation. Click here for an example of Task 1.

Task 2 – Develop Safety Projects
This task involves applying the decision process to identify a specific countermeasure for each candidate site selected for safety investment. This includes providing a detailed description of the site (route number, mile point, intersecting roadway, segment termini, etc.), identifying the specific strategy selected, estimated implementation cost, and summary on how the site scored with the risk factors. Click here for an example of Task 2.

Task 3 – Prioritize Safety Project Implementation
The final task is to identify the order in which projects will be implemented, taking into consideration factors such as funding, other programmed projects, time to develop project plans, amount of public outreach needed, etc. The prioritized list of locations infers a particular order based on the number of risk factors present at a given location. Click here for an example of Task 3.

Additional information is available on the Step and Tasks in the Systemic Safety Project Selection Tool, which will be available soon.

 

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