road safety assessments: who, what, how, when, where and why
DESCRIPTION
Ruben Hovanesian June 27, 2012. Road Safety Assessments: Who, What, How, When, Where and Why. Poll. Public Agencies? Private Agencies?. Overview. Road Safety Assessments What How When Who Why Example. What is it?. What is an RSA?. Road Safety Assessment (RSA) - PowerPoint PPT PresentationTRANSCRIPT
Road Safety Assessments: Who, What, How, When, Where and Why
Ruben HovanesianJune 27, 2012
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Poll
Public Agencies? Private Agencies?
3
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!