Road Safety Audit

Hossein Naraghi

CE 590 Special Topics

Safety

June 2003

Time spent: 9 hrs

Road Safety Audit A complementary action to accident

reduction is accident prevention The aim is to ensure that the road system

is safe One of the key component of accident

prevention involves the use of safety checks or safety audits• The focus is on the design of new road and

traffic schemes• Sometimes the focus is on the existing roadway

Definition and objectives of road safety audit

Significant improvements in safety are not automatic safety must be Systematically designed into each

project Highway designers must seek safety

opportunities specific to each project and apply sound safety and traffic engineering principles

This process which aimed at preventive road safety engineering is the road safety audit

Definition and objectives of road safety audit (continued)

The Roads and Traffic Authority of New South Wales describe safety audit as “A means of checking the design,

implementation and operation of road projects against a set of safety principles as a means of accident prevention and treatment”

Essential elements The essential elements of the road

safety audit process are A formal process and not an informal

check An independent process Carried out by someone with appropriate

experience and training Restricted to road safety issues

Safety audit objectives The objective of the road safety audit is to

Minimize the risk and severity of road accidents that might be affected by the road project at the site or nearby network

Minimize the need for remedial work after construction

Reduce the whole-life costs of the project Improve the awareness of the safe design

practices by all of those involved in the planning, design, construction and maintenance of roads

Safety audit objectives (continued)

Road safety audit can work in two ways:1. Removing preventable crash producing

elements at the planning or design stage• e.g. inappropriate intersection layouts

2. Mitigating the effects of remaining or existing problems• Inclusion of suitable accident reducing

features• Anti-skid surfacing• Guard fencing• Traffic control devices• Delineation, and etc

Safety audit objectives (continued)

Highway designers and traffic engineers have always practiced a form of safety audit

What is important about the recent emergence of the practice is Its specific incorporation as a discrete phase Independent of the designer Development of defined auditing procedures

• Followed within a road or traffic agency• May be incorporated within an overall quality

management or quality assurance process within the agency

Use of road safety audit The concept of road safety audit

emerged initially in Britain in 1980’s It was one of the key response to the

Government’s target of reducing road fatalities by one-third by the year 2000

It was given impetus by the preparation of two key publications1. Road Safety Code of Good Practice

• Local Authorities Association, 1989

2. Guidelines for the Safety Audits of Highways• Institution of Highways and Transportation, 1990

Use of road safety audit (continued)

Road safety audit was made mandatory for all national trunk roads and motorways in 1991

In the light of the success of British experiences the process has also adopted in New Zealand began the safety audit process in

1992• From 1993, safety audit was mandatory in 20 percent

sample of State highway projects• A comprehensive road safety audit policy has been

prepared The World Bank has begun to show an interest in

the safety audit subject in 1992

Application of road safety audit

Road safety audit may be carried out at any or all following stages Stage 1: Feasibility

• A safety audit can influence• the scope of a project• route choice • selection of design standards • impact on existing road network • route continuity • provisions of interchanges or intersections • access control • number of lanes • route terminals, stage development, etc

Application of road safety audit (continued)

Stage 2: Draft design This audit stage is undertaken on

completion of a draft plan or a preliminary design. Typical considerations include

• Horizontal and vertical alignment• Sightlines• Intersection layouts• Lane and shoulder width• Super elevation• Overtaking lanes• Provisions for parked and stationary vehicles• Provisions for bicyclists and pedestrians• Effects of departures from standards and guidelines• Safety during construction, etc

Application of road safety audit (continued)

Stage 3: Detailed design This stage is on completion of detailed

design, normally before preparation of contract documents, considerations include:

• Line markings• Signing• Delineation• Lighting• Intersection details• Clearance to roadside objects• Provision to road user groups with special requirements• Temporary traffic management and control during

construction

Application of road safety audit (continued)• Drainage• Roadside objects• Landscaping• Batters• Guard fencing, etc

Stage 4: Pre-opening Prior to opening of the road to traffic

• The audit would involve driving, riding and walking through the project to check the adequacy for the needs of all road users

• Involve night-time inspection• Inspection of both wet and dry conditions

Application of road safety audit (continued)

• It would consider similar issues raised in stage 2 and 3, but with the view of assessing their adequacy as actually constructed

• Taking specific note of variations that might have occurred from the plans in the process of construction

Stage 5: In-service Systematic examination of sections of the

existing road network to assess the adequacy of the road, intersection, roadside, etc from an explicit safety viewpoint• This can have two applications

Application of road safety audit (continued)

• Monitoring a new scheme after it is opened to traffic

• i.e. in the weeks and months following the stage 4 audit

• Safety audit of an existing road network with a view of identifying safety-related deficiencies

Although all 5 of the above stages can and have been used• In practice the first and last of these stages

are less common

Safety audit process The key requirements are

Management commitment• Auditors are outsiders brought in to find things

wrong with their work• Audit process brings specialists advice to the design

team• In relation to implementation of the safety

management system in the USA, Hall 1993 was concerned about

• Other functional units may believe that the accomplishment of their goals are threatened by the infringement of safety management initiatives into their territory

• Care should be taken throughout system implementation to maintain an atmosphere of cooperation and mutual respect among affected functional areas

Safety audit process (continued)

An agreed road safety audit process The process aim to reduce the whole life cost

of a scheme• Although there will be cost of audit process, it is

worthwhile if offset against the potential for savings elsewhere

• The savings may be from• Timely alteration to plans

• It is much cheaper to change a detail on a plan than to replace or remove a feature once installed

• Subsequent accident prevention• Reduction in the costs resulting from litigation

Safety audit process (continued)

An independent auditor or audit team There must be a designated procedure

for acting upon the audit report If a specialist team is used, one of three

procedures can be followed1. Prior agreement to accept safety audit

recommendations2. Assessment of the audit report by the

client3. Assessment of the audit report by the

designer

Safety audit process (continued)

An agency developing a road safety audit process will need to determine which of these procedures to follow, depending upon its own expertise and the role of safety auditing within a wider institutional framework such as quality management

No matter which procedure is adopted the key factors are as follow The audit team must include specialist

knowledge of road safety engineering Safety audit findings should be formally

documented and reported at each step of the audit process

Safety audit process (continued)

A set of checklists Use of checklists which show type of issues

and problems that can potentially arise at the relevant stage of the project

Checklists are a memory prompt When using checklists, it is less likely to

overlook problems They can not be a substitute for expertise One of the main benefits of checklists is that

designers can use that to audit themselves before their work gets to the auditor

Safety audit process (continued)

Training and development of expertise The size of the audit team depends on the size

and complexity of the project British experience says at the feasibility or

layout design stage, three-person team would be suitable, Comprising • A road safety specialist with experience in crash

investigation and safety engineering principles and practice

• A highway design engineer• A person with experience in safety audit, who is able

to generate discussion and assist in the procedure

Safety audit process (continued)

Monitoring and evaluation Process of monitoring and evaluation

involves three aspects•Procedures, problem encountered, and

effectiveness of the system•Critical appraisal of the checklists and

their use•Evaluation of costs and resources by

scheme type and stage

Liability The Australian guidelines include a chapter

on legal issues, with following conclusion No case involving a road safety audit has yet

come before a court The legal implication must be speculative The predictions are not guesswork, they are

based upon well established principles of tort law

Safety audit will create a safer road environment

Liability (continued) A major objective of litigation is encourage

safety, therefore the use of safety audit will be encouraged by the legal system

Roads can be made safe by different methods• Black spot treatment• Periodic inspection• Adoption of higher standards of engineering

practice• Greater allocation of funds and road safety audits

It is for highway authorities to decide which mix of these is best for a given project

Audits of existing roads A formal program of safety audit of existing

roads can be an important component of the overall audit process The aim of this stage of audit is to identify any

existing safety deficiency of design, layout, and street furniture which are not consistent with road’s function

There should be consistency of standards Many items may be related to maintenance of the

road, therefore the benefit of the safety audit process is to ensure that these items are placed on the maintenance program

Audit of development projects

An extension of the road safety audit in some local authorities is to require that development proposals be audited, these may include A new commercial development which will

generate traffic on an existing road A residential development which involves street

construction In a road safety audit context, these would need

to be independently audited and a report submitted as part of development application

Audit of development projects (continued)

Audit report of development projects may address The safety impact of peak period

congestion The generation of pedestrians and

bicyclists movements across existing roads

The safe provision of public transportation Vehicular and pedestrian access to the site

Audit of development projects (continued) Adequacy of parking provision from a

safety viewpoint Pedestrian-vehicle conflicts on and

adjacent to the site Type and layout of intersections and new

road alignments Speeds within the site visibility

Effectiveness of road safety audit

Although safety audit is relatively a new technique, evidence is emerging that safety audit is a cost-effective safety measure A formal requirement that a project be subjected

to a safety audit will very likely lead to improved safety

UK experience suggests that for individual schemes perhaps one-third of crashes have the potential for removal by safety audit

It should be noted that the resources need to be devoted to safety audit are in fact quite small

Effectiveness of road safety audit (continued)

UK experience suggests that one safety auditor is required to cover an area experiencing 1000 casualty crashes per year

Australian and New Zealand experience suggest that safety audit adds 4% to road design costs without consideration of whole life savings from safety audit

There have been some attempt to quantify the benefits of safety audit

• One highway authority in Scotland, 1991 has estimated that one-third of future accidents at road improvements are preventable by audit, and that a one percent accident saving per year worth $1.5 million at resource of $100,000, a benefit:cost ratio of 15:1

Benefits of road safety audit Austroads, 1994 summarizes the benefits of

road safety audit The possibility of crashes on the road network can

be reduced The severity of crashes can be reduces Road safety is given greater prominence in the

mind of road designers and traffic engineers The need for costly remedial work is reduced The total cost of the project to the community is

reduced