In 1994, the Institute of Transportation Engineers (ITE) responded to the Federal Highway
Administration (FHWA) Highway Safety Program Guidelines by recommending U.S. "agencies
should introduce the concept of road safety audit into their systems." In an effort to prevent
crashes on new or existing roads, some countries are already using the road safety audit process,
defined as:
a formal examination of an existing or future road or traffic project, or any project that
interacts with road users, in which an independent, qualified examiner looks at the
project's accident potential and safety performance.
To develop a report on current use and future potential of road safety audits, the ITE established
an international committee headed by Kenneth W. Ogden. Ogden holds a Ph.D. in civil
engineering from Monash University in Melbourne and is the head of the Monash Transport
Group in the Department of Civil Engineering at Monash University. A summary of the
committee's report appeared in the February 1995 issue (Volume 65, Number 2) of the ITE
Journal. Written by members of the ITE's committee on road safety audits, the article was
entitled "Road Safety Audit: A New Tool for Accident Prevention."
Why Road Safety Audits?
Traditional engineering solutions to highway safety problems focused on crash reduction--developing corrective measures for sites where crashes happened frequently. The article
suggested that political pressure has prompted a move toward crash prevention--designing safer
new roads and identifying and modifying existing roads before crash statistics revealed a
problem. Road safety audits can be key processes in crash prevention.
Road safety audits foster safer road projects in two ways: (1) promoting elimination or
mitigation of safety hazards (such as dangerous intersection layouts) during the planning and
design stages of roadway construction and (2) encouraging incorporation of crash-reducing
features (such as traffic control devices, delineation, and guardrails).
According to the article, safety audits should:
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- Minimize the risk and severity of road crashes that may be affected by the road project at
the site or on the nearby network.
- Minimize the need for remedial works after construction.
Reduce the whole-of-life costs of the project.
- Improve the awareness of safe design practices by everyone involved in the planning,
design, construction and maintenance of roads.
International Perspective
Road safety audits are becoming a separate component of highway safety efforts in countries
around the world.
United Kingdom -- As part of a Department of Transportation goal to reduce highway casualties
one-third by the year 2000, mainland Britain passed legislation requiring action. Results have
included publication of codes and guidelines and, since 1991, mandated safety audits for all
United Kingdom national trunk roads and freeways.
Australia -- Austroads, Australia's national association of traffic and road agencies, had begun
work on guidelines for a national road safety audit program. Throughout the country, the states
were at different points in developing safety audits. New South Wales was auditing 20 percent
of existing roads each year, and the State of Victoria audited all major construction projects, 20
percent of other projects, and 10 percent of maintenance work.
Australia had written guidelines for safety audits of existing roads. They recommended a one-stage detailed inspection of short lengths of roadway (under 19 miles). For longer sections, a
two-stage audit would first include assessment of major problems and then detailed inspection of
problem areas.
New Zealand -- Beginning with a pilot program in 1992, New Zealand moved into mandatory
safety audits for 20 percent of state highway projects in 1993.
United States -- While no formal program existed in the U.S. for implementing road safety
audits, the FHWA's "Management Approach to Highway Safety: A Compilation of Good
Practices" (1991) called for "identifying, investigating, setting priorities and correcting hazardous
or potentially hazardous situations" and encouraged having a process to incorporate safety
considerations into highway construction projects.
Conducting Road Safety Audits
Road construction projects involve five stages; safety audits are appropriate during any or all of
these stages.
Feasibility -- According to the article, information from a safety audit during the feasibility study
for a project may affect such factors as: "the scope of a project, route choice, selection of design
standard, impact on the existing road network, route continuity, provision of interchanges or
intersections, access control, number of lanes, route terminals, stage development, and more."
Layout or Preliminary Design -- An audit completed during this stage of road construction
might consider: "horizontal and vertical alignment, sightlines, intersection layouts, land and
shoulder width, pavement crossfall and superelevation, overtaking lanes, provision for parked
and stationary vehicles, provision for cyclists and pedestrians, effects of departures from
standards and guidelines, safety during construction, and so on."
Detailed Design -- At this stage, before preparation of contract documents, a road safety audit
would look at: "line markings, signing, delineation, lighting, intersection details, clearances to
roadside objects, provision for road user groups with special requirements (for instance,
pedestrians, cyclists, people with disabilities, trucks and buses), temporary traffic management
and control during construction, drainage, poles and other roadside objects, landscaping, batters
[slopes] and guard fencing."
Preopening -- At this stage, the audit team would walk or drive through a project to check on the
quality of completed safety features. They would inspect many of the same items as were
considered during the design process, and they would try to be at the project during different
conditions--day and night, wet and dry, etc.
In-service -- This type of audit is appropriate for new construction and for existing roads. The
team systematically identifies weaknesses in the functioning of safety features while the road is
open to motorists.
The Road Safety Audit Process
To avoid the perception that safety audits reflect a lack of faith in the competence of a project's
designers and engineers, the agency's program should make safety audits integral to the
construction process. Where audits define safety as a separate consideration in roadway
construction, attention to safety features increases. The authors argued that this attention to
safety would reduce the total cost of a project by promoting timely alterations to construction
plans and would lower costs associated with finished roadways by decreasing the number of
crashes and reducing litigation.
The specialists comprising a road safety audit team may come entirely from outside the agency,
partly from outside, or completely from inside. British three-person safety audit teams generally
include: (1) a road safety engineering specialist with expertise in crash investigation, (2) a
highway design engineer, and (3) a person experienced in the safety audit procedure. Specialists
in various areas join the team during certain audit stages; e.g., the engineer who will have
maintenance responsibility for the road would be involved in a preopening audit.
Whatever the composition of the team, article authors listed six key factors to consider in
adopting an audit method:
The audit team must include specialist knowledge of safety engineering.
The findings of the audit should be documented and reported formally at each stage of
the audit process.
The reasons for various elements of audit advice should be documented formally.
The reasons for rejecting any element of advice should be explained to the scheme
designer.
Provisions for arbitration should be made.
Independence of audit must be maintained, and there should be an awareness of possible
litigation if there are subsequent failures.
To help team members remember the myriad items to check during a road safety audit, the article
recommended using checklists or prompts. Computerized representative checklists are available;
however, the authors reminded the reader that no checklist is a substitute for expertise and audits
should always include on-site visits as well as plan review. An integral part of the audit is
monitoring and evaluating the process itself. Auditors should monitor the effectiveness of
procedures and checklists and keep track of costs and benefits.
Agencies were only beginning to systematically use road safety audits; therefore, data on cost
effectiveness was scarce. The United Kingdom had projected that "one-third of accidents have
the potential for removal by safety audit." Scotland computed that preventing 1 percent of
crashes per year would save about $1.5 million (in U.S. dollars) annually.
Liability Issues
At the time this article was written, Australian guidelines claimed, "No case involving
road safety audit has yet come before a court." These guidelines contended, however, that
previous litigation of highway cases had sought to encourage safety improvements; it follows,
therefore, that the court will advocate road safety audits. The courts, however, seek results and
not merely process. To the extent that road safety audits contribute to overall improvement of
highway safety, agencies will reduce liability by conducting audits. Conversely, "[h]ighway
authorities that fail to adopt safety audits or comparable processes run a higher risk that legal
liability will be imposed."
Conclusion
The authors concluded road safety audits can accomplish crash prevention by "get[ting] it
right the first time." To be effective, audit team members must be independent, competent, and
experienced persons who have received adequate training. In addition, people making decisions
on carrying out audit findings must be accountable to do so properly. An effective audit will help
agencies lower the total cost of road projects and reduce potential for expensive litigation.
The complete ITE committee report on road safety audits is available from the ITE
Bookstore. For more information, contact the Institute of Transportation Engineers at 525
School Street S.W., Suite 410, Washington, D.C. 20024-2797 or call (202) 554-8050.