what are road safety audits?
Post on 23-Jan-2018
432 Views
Preview:
TRANSCRIPT
Session 2: Slide 1Copyright © 2016 H J S Lotter. All rights reserved.
What are Road Safety Audits?
Two ways of improving safety:
• Accident reduction(reactive)
• Accident prevention(proactive)
Session 2: Slide 2Copyright © 2016 H J S Lotter. All rights reserved.
Accident prevention:
For example road safety audits
Session 2: Slide 3Copyright © 2016 H J S Lotter. All rights reserved.
• Use knowledge or research to reduce the risk (potential) for accidents to occur prior to the road being built, reconstructed or upgraded
Session 2: Slide 4Copyright © 2016 H J S Lotter. All rights reserved.
Advantages to this approach
• not necessary for build-up of extraordinary accident history before locations can be identified and prevention can be taken
• much cheaper changing plans than implementing countermeasures on a road open to the public
Session 2: Slide 5Copyright © 2016 H J S Lotter. All rights reserved.
Definition of road safety audit:
“A formal systematic process for the examination of new road projects by an independent and qualified audit team, in order to detect any defects likely to result in a crash”
Session 2: Slide 6Copyright © 2016 H J S Lotter. All rights reserved.
Commission audit
Approve Audit Team
Compile / Issue Audit
Brief
Assess Audit Brief (and associated
Information)
Compile / Issue the
Audit Report
Review Problems
and Recommen
dations
Compile / Issue
Exception Report
Undertake Site Visit
Implement Design
Changes
Formal systematic process
Session 2: Slide 7Copyright © 2016 H J S Lotter. All rights reserved.
Independent audit team
Auditor
Designer
Session 2: Slide 8Copyright © 2016 H J S Lotter. All rights reserved.
Qualified audit team
Session 2: Slide 9Copyright © 2016 H J S Lotter. All rights reserved.
Year 1 Year 3Year 2 Year 4
Road safety engineering or crash investigation experienceSTART
Qualify as Observer
4-day road safety audit
course
Qualify as Member
3 road safety audits as observer (2 @ design stage)
Qualify as Leader
2 days CPD
Year 5
On-going
Session 2: Slide 10Copyright © 2016 H J S Lotter. All rights reserved.
5-day Road safety
engineering or crash inv
course
Road design, construction or traffic engineering experience
2 days CPD2 days CPD2 days CPD 2 days CPD
5 road safety audits as member (3 @ design stage)
On-going
On-going
On-going
Defects likely to result in a crash
Session 2: Slide 11Copyright © 2016 H J S Lotter. All rights reserved.
Session 2: Slide 12Copyright © 2016 H J S Lotter. All rights reserved.
From a road users point of view
Session 2: Slide 13Copyright © 2016 H J S Lotter. All rights reserved.
Session 2: Slide 14Copyright © 2016 H J S Lotter. All rights reserved.
Session 2: Slide 15Copyright © 2016 H J S Lotter. All rights reserved.
Session 2: Slide 16Copyright © 2016 H J S Lotter. All rights reserved.
An audit is not:
• An opportunity to redesign
• A design check
• A crash investigation
Session 2: Slide 17Copyright © 2016 H J S Lotter. All rights reserved.
Session 2: Slide 18
• Preliminary design stage (Stage 1)
Session 2: Slide 19Copyright © 2016 H J S Lotter. All rights reserved.
• Draft design stage (Stage 2)
Session 2: Slide 20Copyright © 2016 H J S Lotter. All rights reserved.
• Detailed design stage (Stage 3)
Session 2: Slide 21Copyright © 2016 H J S Lotter. All rights reserved.
• Work Zone traffic management stage (Stage 4)
Session 2: Slide 22Copyright © 2016 H J S Lotter. All rights reserved.
• Pre-opening stage (Stage 5)
Session 2: Slide 23Copyright © 2015 H J S Lotter. All rights reserved.
• Other types of audit:
Road safety appraisal (audits of existing roads)
Land use developments audits
Specific Road User Groups
Session 2: Slide 24Copyright © 2016 H J S Lotter. All rights reserved.
Audit stages
Session 2: Slide 25
Audit Team
• Team Leader
• Team Members
Session 2: Slide 26Copyright © 2016 H J S Lotter. All rights reserved.
Assisting Audit Team
• Observers
• Specialist advisor (if required)
Session 2: Slide 27Copyright © 2016 H J S Lotter. All rights reserved.
• Local police
• Maintaining authority
• Specific road user group expert
Session 2: Slide 28Copyright © 2016 H J S Lotter. All rights reserved.
Why are audits necessary?
Session 2: Slide 29Copyright © 2016 H J S Lotter. All rights reserved.
But we already have standards!
Session 2: Slide 30Copyright © 2016 H J S Lotter. All rights reserved.
Standards …..
may be old and no longer relevant
Session 2: Slide 31Copyright © 2016 H J S Lotter. All rights reserved.
Session 2: Slide 32Copyright © 2016 H J S Lotter. All rights reserved.
Session 2: Slide 33Copyright © 2016 H J S Lotter. All rights reserved.
Individual road elements …..
designed to standard, may be quite safe in isolation but may, when combined with other standard elements, be unsafe!
Session 2: Slide 34Copyright © 2016 H J S Lotter. All rights reserved.
Session 2: Slide 35Copyright © 2016 H J S Lotter. All rights reserved.
Session 2: Slide 36Copyright © 2016 H J S Lotter. All rights reserved.
Session 2: Slide 37Copyright © 2015 H J S Lotter. All rights reserved.
A junction on the outside of a horizontal curve provides good site distance from the side road
Source: AUSTROADS Safety Audit (1994)
Session 2: Slide 38
A deceleration lane allows vehicles to slow down off the main running lane, reducing the
risk of rear-end shunts
Source: AUSTROADS Safety Audit (1994)
Session 2: Slide 39
But if these two elements are combined, they can result in left-turning vehicles hiding
following vehicles, increasing the risk of side-impact accidents
Source: AUSTROADS Safety Audit (1994)
Session 2: Slide 40
Session 2: Slide 41Copyright © 2015 H J S Lotter. All rights reserved.
Session 2: Slide 42Copyright © 2015 H J S Lotter. All rights reserved.
Standards …..
are not only developed for safety but also for other reasons, e.g. traffic capacity and to keep costs low (often conflicting with safety!)
Session 2: Slide 43Copyright © 2016 H J S Lotter. All rights reserved.
Session 2: Slide 44Copyright © 2015 H J S Lotter. All rights reserved.
Standards …..
usually cover general or common situations, not all situations
Session 2: Slide 45Copyright © 2016 H J S Lotter. All rights reserved.
Cost or space constraints …..
may require deviation from standardsSession 2: Slide 46Copyright © 2016 H J S Lotter. All rights reserved.
Design of road environment ..
may differ from how drivers actually perceive them, especially
with respect to speedSession 2: Slide 47Copyright © 2016 H J S Lotter. All rights reserved.
Audits are not expensive
• Road Safety Audits are only a small part of design and project costs: 1% to 2% of total design costs
0.5% of total project costs
Session 2: Slide 48Copyright © 2016 H J S Lotter. All rights reserved.
• Cost of Safety Audits consist of: Small cost to undertake audits
Short delay in project
Small cost of redesign
Small cost of modifying construction
Session 2: Slide 49Copyright © 2016 H J S Lotter. All rights reserved.
• Design changes cost a few 1,000 Rand
• But construction changes cost a few 100,000 Rand!!
• So need to do audits at the beginning of the project!
Session 2: Slide 50Copyright © 2016 H J S Lotter. All rights reserved.
Benefits of audits
• Improving design standards and procedures through the feedback
• Enhancing consistency of the road network
• Ensuring more explicit provision is made for safety needs of vulnerable road users
Session 2: Slide 51Copyright © 2016 H J S Lotter. All rights reserved.
• Reducing the number and severity of crashes
• Reducing the overall cost of schemes (easier and cheaper to correct projects on drawing board than after implementation)
Session 2: Slide 52Copyright © 2016 H J S Lotter. All rights reserved.
Scientific basis
• Audited sites could save at least one casualty per site per year (Surrey)
• Average the cost of rectifying sites aftera project was constructed was R150,000 more than the cost of implementing audit recommendations (during design and/or construction): (TRL)
Session 2: Slide 53Copyright © 2016 H J S Lotter. All rights reserved.
• Systematic application of road safety audit procedures across Britain was estimated to have the potential to reduce personal injury crashes by 3% (Sabey)
• First year rate return (FYRR) of audits are between 149 % and 600 % (Denmark & UK)
Session 2: Slide 54Copyright © 2016 H J S Lotter. All rights reserved.
Questions?
Session 2: Slide 55Copyright © 2016 H J S Lotter. All rights reserved.
top related