Implementation of Federal Highway Administration Proven Safety Countermeasures (2025)
Chapter: 1 Introduction
CHAPTER 1
Introduction
State departments of transportation (DOTs) implement various countermeasures on their transportation networks to improve transportation safety. To support these efforts, the Federal Highway Administration (FHWA) Office of Safety developed a list of proven safety countermeasures (PSCs) along with a website that includes brief descriptions, information sheets, and additional references. As noted by FHWA, these PSCs help reduce fatalities and serious injuries on the nation’s roadways and are suggested for use by state DOTs and other agencies (FHWA 2024a). As of 2024, there are 28 of these PSCs available. There is a need for a review of state DOT practices regarding the use of the FHWA PSCs.
Objectives and Scope
The objective of the synthesis is to review and document the practices of state DOTs regarding the implementation of the FHWA PSCs. The scope of the synthesis includes
- FHWA PSCs piloted, implemented, or adopted as policy or procedures by DOTs;
- The extent, scale, and frequency to which each countermeasure has been implemented, including (but not limited to) FHWA Every Day Counts stages of implementation and factors affecting different implementation approaches within a given state (e.g., geographic location, climate, traffic volume, crash history);
- DOTs’ evaluation of the FHWA PSCs after implementation; and
- Barriers to the implementation of the FHWA PSCs and DOTs’ modifications (physical changes made to how countermeasures are implemented) and strategies (approaches or methods used to implement the countermeasures) to overcome those barriers.
Definitions
In this synthesis, the following definitions are used:
- Proven Safety Countermeasure (PSC): One of the 28 countermeasures or strategies, as designated by FHWA, that are effective in reducing fatalities and serious injuries because of roadway crashes in the United States.
- Department of Transportation (DOT): A government agency from the 50 states or District of Columbia that coordinates and oversees transportation-related matters within its jurisdiction, including potential implementation of the FHWA PSCs.
Overview of FHWA PSCs
As noted on FHWA’s PSC website (FHWA 2024a), the 28 PSCs are grouped into five categories: speed management, pedestrian/bicyclist, roadway departure, intersections, and crosscutting. A list of FHWA PSCs by category is shown in Table 1.
Table 1. List of FHWA PSCs by category (Source: FHWA 2024a).
| Category | PSC |
|---|---|
| Speed Management | Appropriate Speed Limits for All Road Users |
| Speed Safety Cameras (SSCs) | |
| Variable Speed Limits (VSLs) | |
| Pedestrian/Bicyclist | Bicycle Lanes |
| Crosswalk Visibility Enhancements | |
| Leading Pedestrian Interval (LPI) | |
| Medians and Pedestrian Refuge Islands in Urban and Suburban Areas | |
| Pedestrian Hybrid Beacons (PHBs) | |
| Rectangular Rapid Flashing Beacons (RRFBs) | |
| Road Diets | |
| Walkways | |
| Roadway Departure | Enhanced Delineation for Horizontal Curves |
| Longitudinal Rumble Strips and Stripes on Two-Lane Roads | |
| Median Barriers | |
| Roadside Design Improvements at Curves | |
| SafetyEdge | |
| Wider Edge Lines | |
| Intersections | Backplates with Retroreflective Borders |
| Corridor Access Management | |
| Dedicated Left- and Right-Turn Lanes at Intersections | |
| Reduced Left-Turn Conflict Intersections | |
| Roundabouts | |
| Systemic Application of Multiple Low-Cost Countermeasures at Stop-Controlled Intersections | |
| Yellow Change Intervals | |
| Crosscutting | Lighting |
| Local Road Safety Plans (LRSPs) | |
| Pavement Friction Management | |
| Road Safety Audit (RSA) |
Synthesis Methodology
The synthesis approach included a literature review, survey, and case examples. The existing literature from many different sources, including guides, evaluation studies, websites, DOT policies and standards, and other resources, was reviewed and synthesized. An online survey was distributed to the DOTs for all 50 states and the District of Columbia. Responses were received from 49 DOTs, leading to a 96% response rate. Follow-up interviews were conducted with representatives from six DOTs to develop case examples of DOTs’ experiences with FHWA PSCs.
Synthesis Organization
The chapters of this synthesis are organized as follows:
- Chapter 2 describes the comprehensive literature review of FHWA PSC resources, including guides, evaluation studies, websites, DOT policies and standards, and other resources.
- Chapter 3 provides information on DOT practices based on the survey results.
- Chapter 4 contains case examples for six DOTs.
- Chapter 5 presents a summary of synthesis findings and recommendations for future research.
- The text of the report is followed by a list of references and a list of abbreviations.
- Appendices (Table 2) provide supplemental information for how information was gathered, along with a Summary of Existing Literature, Guidance, and Policies for FHWA PSCs.
Table 2. Synthesis appendices.
| Appendix | Title |
|---|---|
| A | Survey Questionnaire |
| B | List of Responding DOTs and Individual Survey Responses from DOTs |
| C | Typical Case Example Interview Questions |
| D | Summary of Existing Literature, Policies, and Guidance for FHWA PSCs |
