Road safety audits (RSAs) have emerged as a simple and effective tool for improving the safety of roads and intersections. When conducted early in the design process, an RSA can identify possible safety problems so that they can be corrected before the design progresses any further and before the problems are built into the project. RSAs conducted toward the end of the design process (or even during and after construction) are useful for suggesting low-cost measures to improve safety.
An RSA is a formal safety performance examination of an existing or future road or intersection by an independent team. The multidisciplinary team focuses on road safety. Other aspects of the project such as geometric and financial constraints are considered, but the job of the RSA team is to identify the safety implications of the project and suggest how safety could be improved. RSA teams have examined:
- The safety of pedestrians and cyclists;
- Connections to and consistency with existing infrastructure beyond the project limits;
- How a project will perform under winter road conditions; and
- How various project elements interact, especially combinations of minimum standards.
An RSA does not simply identify potential issues; it also identifies potential solutions. The team is aware that some situations may be unavoidable in a road design. The job of the RSA team is to identify whether these may affect safety and, if so, suggest some likely measures to improve the safety of the road or intersection.
For example, land constraints may result in the need to design a horizontal curve having a radius below the minimum design value for expected speeds. The RSA team can suggest potential measures to identify this location to drivers (appropriate signing) and encourage lower approach speeds (narrower lanes or transverse rumble strips), which could be implemented at a reasonable expense.
Audits in action
To demonstrate the effectiveness of RSAs, the Federal Highway Administration’s (FHWA) Office of Safety Design sponsored 10 RSAs with the aim of demonstrating their practical usefulness on a variety of projects ranging from $150,000 worth of urban intersection improvements to an $800 million interchange at a variety of design stages from conceptual through final and for a variety of agencies at the county, city, tribal and state level.
The following demonstrates the eight-step RSA process:
The first steps involve identifying the project to be audited (Step 1) and assembling an RSA team (Step 2). The RSA team is composed of three to five people: one or two engineers having road safety, operations or design experience and specialists (e.g., pedestrian/bicyclist, human factors, maintenance, enforcement, emergency-response staff, commercial vehicle, etc.) who can address the particular challenges of the project being audited.
All RSAs in the FHWA case studies project were conducted in a workshop setting that took two to three days. The workshops began with a pre-audit startup meeting (Step 3) attended by the project owner, the design team (if applicable) and the RSA team. At this meeting, the owner described the objectives of the road project, the design team described the road design (along with its challenges) and the RSA team described the RSA process.
Following the startup meeting, the RSA team conducted daytime and nighttime field reviews (Step 4) to observe the conditions in which the proposed design or existing road operates, looking at things like typical speeds, traffic mix and surrounding land uses. The RSA team then conducted the analysis workshop (Step 5), in which all RSA team members reviewed the design or as-built drawings, examining features such as road geometry, sight distances, clear zones, drainage, signing, lighting and barriers. On the basis of the drawings and field review, the RSA team identified and prioritized those features of the project that could generate a risk of higher severity and frequent crashes. For each of these safety issues, the RSA team generated a list of possible ways to mitigate the crash potential.
At the end of the RSA workshop, the owner, design team and RSA team got together again to discuss preliminary findings (Step 6). This meeting gave the owner, the design team and the RSA team a chance to discuss not only the initial findings and suggestions, but also additional or alternative ways to improve the safety of the project.
Within two weeks, the RSA team had written and issued the RSA report containing a prioritized list and description of the safety issues identified, along with suggestions for improvements. The owner and design team then wrote a brief letter (Step 7) responding to the safety issues and identifying the action(s) to be taken or explaining why no action could be taken. As a final step, the owner used the RSA findings to achieve safety improvements as and when policy, manpower and funding permit (Step 8).
Lessons learned
Over the course of the RSA case studies project, the RSA teams have identified several key elements that help to make a successful RSA. These lessons learned will be detailed in the case studies book that is the final product of this project. Four of these elements are discussed below:
1. The RSA team must acquire a clear understanding of the project background and constraints.
At the RSA workshop startup meeting, a frank discussion of the constraints and challenges encountered in the design of the audited project is critical to the success of the RSA. It is crucial that the RSA team understands the compromises that were part of the design process. Knowledge of these constraints helps the RSA team to identify mitigation measures that are practical and reasonable.
2. The RSA team and design team need to work in a cooperative fashion to achieve a successful audit result. It is important to maintain an atmosphere of cooperation among all participants in the audit process—the design team, RSA team and owner.
The RSA team should be consistently positive and constructive when dealing with the design team. Many problems can be avoided if the RSA team maintains effective communication with the design team during the audit, including the opportunities presented in the startup and preliminary findings meetings, to understand why roadway elements were designed as they were and whether mitigation measures identified by the auditors are feasible and practical. This consultation also gives the design team a heads-up regarding the issues identified during the RSA, as well as some input into possible solutions. The heads-up can reduce apprehension, and therefore defensiveness, concerning the RSA findings.
The cooperation of the design team is vital to the success of the RSA. An RSA is not a critical review of the design team’s work, but rather a supportive review of the design with a focus on how safety can be further incorporated into it. Cooperation between the RSA team and design team usually results in a productive RSA, since the RSA team will fully understand the design issues and challenges as explained by the design team, and suggested mitigation measures—as discussed in advance with the design team—will be practical and reasonable.
Support from the owner is vital to the success of individual RSAs and the RSA program as a whole. It is essential that the owner commits the necessary time within the project schedule for conducting the RSA and incorporating any improvements resulting from it, as well as the staff to represent the owner in the RSA process (team members independent of the project and a representative at the startup and preliminary findings meetings).
3. A local champion can greatly help facilitate the establishment of RSAs.
Wilson and Lipinski noted in their recent synthesis of RSA practices in the U.S. that the introduction of RSAs or an RSA program can face opposition based on liability concerns, the anticipated costs of the RSA or of implementing suggested changes and commitment of staff resources. To help overcome this resistance, a local champion who understands the purposes and procedures of an RSA, and who is willing and able to promote RSAs on at least a trial basis, is desirable. Thus, measures to introduce RSAs to a core of senior transportation professionals can help to promote their wider acceptance.
4. The RSA field review should be scheduled to coincide with important site conditions.
The RSA team should visit the project site when traffic conditions are typical or representative. For example, the RSA in Yellowstone National Park was conducted at the start of the park’s summer season when visitor volumes were increasing. Consequently, the RSA team observed parking and circulation issues that were characteristic of the park’s high-volume summer season. In contrast, the RSA in Cincinnati was conducted in late December after classes at a nearby university had ended. The RSA team was consequently unable to observe the impact of university traffic at the site. Although this did not significantly affect the RSA findings, scheduling the field review to observe typical or usual traffic conditions is preferable, since it allows the RSA team to see how regularly recurring traffic conditions and road-user behavior may affect safety.
The final steps
The RSA case studies project sponsored by the FHWA Office of Safety Design has been well received by the participating transportation agencies. The project has exposed local and state agencies to the concepts and practices of an RSA and provided for agency staff members to participate on the RSA team as part of the FHWA project.
The RSA case studies project is nearing completion. The final step in this stage is the production of a book summarizing the results of each road safety audit. Each case study will include photographs, a project description, a summary of key findings, a summary of costs and benefits (as far as possible) and the lessons learned. It is hoped that the case studies will provide local and state agencies with examples and advice that can assist them in implementing RSAs in their own jurisdictions.
Agencies interested in conducting an RSA are encouraged to schedule training by contacting FHWA RSA Program Manager Louisa Ward at [email protected] or the FHWA Resource Center’s lead instructor for RSAs, Craig Allred at [email protected]. Additional resources include a new Peer-to-Peer program (providing free assistance on a first RSA), e-mail: [email protected] and the FHWA website at safety.fhwa.dot.gov/rsa.
