Road Safety Assessments: Who, What, How, When, Where and Why

Ruben HovanesianJune 27, 2012

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Poll

Public Agencies? Private Agencies?

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Overview

Road Safety Assessments What How When Who Why Example

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What is it?

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What is an RSA?

Road Safety Assessment (RSA) Road Safety Audit…but who likes an

“audit”??

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What is an RSA?

Qualitative safety assessment of a roadway The Why and the How Not just What, When, and Where

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What is an RSA?

Identifies current and potential road safety issues

Identifies opportunities for improvements in safety for all road users

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Objective

Reduce crash risk from road elements

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Objective

What roadway elements may present a safety concern? To what extent To which road users Under what circumstances

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Objective

What opportunities exist to eliminate or mitigate identified safety concerns?

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How to do an RSA?

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How to do an RSA

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• Start-up meeting & information exchange

2• Problem identification & site visit

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• Risk analysis & countermeasure identification

4• Prepare RSA summary presentation

5• RSA summary presentation

6• Final report development

7• Response letter

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Start-up Meeting & Information Exchange

Introductions Chain of command

Expectations Knowledge exchange

Documents and previous studies

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Problem Identification & Site Visit

Desk study Identify possible trends Do not attempt to identify solutions

Team visit to site Time determined by crash statistics Drive (walk) the site

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Risk Analysis & Countermeasure Identification

Workshop setting Crash reports reviewed along with site

visit notes Hazard identification

Crash Risk

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Crash Risk

Crash Risk = f (E, P, C)

ExposureHow many road users

are exposed to the

specific risk being

assessed

ProbabilityThe

likelihood of a crash

occurring

ConsequenceThe

severity of a crash once it

happensFrequency Severity

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Frequency

• ≥4 crashes a yearFrequent

• 1 to 3 crashes a yearOccasion

al• <1 crash a year and >1

crash every 4 yearsInfrequen

t

• <1 crash every 4 yearsRare

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Severity

• K• Involve high

speeds or heavy vehicles, pedestrians, or bicycles

Severe

• A• Involve medium

to high speed, head-on, crossing, or off-road crashes

High

• B• Involve medium

to low speeds, left-turn and right-turn crashes

Medium

• C or PDO• Involve low to

medium speeds; rear-end or sideswipe crashes

Low

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A Minimal D SignificantB Low E HighC Moderate F Extreme

Risk Assessment Scale

RISK CATEGORYExpected Severity

Low Medium High Severe

ExpectedCrash

Frequency

Frequent C D E FOccasional B C D EInfrequent A B C D

Rare A A B C

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Prepare RSA Summary Presentation

Crash statistics and analysis Site visit observations

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RSA Summary Presentation

Presented to owner/designer No mandate to open to public Feedback

Extra signage, not appropriate for the situation

Remove unnecessary chevron

Frequency Severity Risk Rating

Rare Low Minimal A$

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Final Report Development

Made without the influence of owner/designer Or politics

Submitted to owner/designer

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Response Letter

Response from owner/designer Notes reasons for situations

Budget Crew Community

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When to do it?

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When to do an RSA?

Pre-construction

To identify potential problems

During Construction

To perform work-zone assessments

Post-construction

To identify current crash hazards Weather Similar situation as the noteworthy crashes or

clusters

Time During the same times as the most significant crashes

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Proactive

Does not necessarily need “X” amount of crashes at “Y” severity

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Who does it?

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Who does the RSA?

3 to 5 person RSA team Interdisciplinary▪ Traffic operations▪ Geometric design▪ Enforcement▪ Road safety

Additional specialty skills are needed

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Who does the RSA?

Owner of roadwayDesign team

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Why do it?

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Why Perform an RSA?

Traditional Safety Review (SR) Road Safety Assessment (RSA)

Reactive only Proactive and reactive

In –house team familiar with project

Interdisciplinary and independent team of law enforcement, specialists, and engineers unfamiliar with the project

Standards compliance Interaction between roadway elements and users

Desk study only Site visit and observation required

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Proactive

Politically good Good Engineering practice Solves the problem, before it’s a

problem

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Interdisciplinary Team

Brings a range of experience and background

Lack of familiarity Provides impartial judgment Owner/designer complacency

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Interaction

How users act and respond Roadway elements and users

Not just compliance

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Example

Crash locations No obvious pattern Serious roll over and road departure

crashes Drinking not a problem

Site visit Poor maintenance of road sides and

signage Low visibility

Crash reports Proximity of drivers’ residence

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Thank you!