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Kerry Wilcoxon, P.E., PTOE, RSP1

State Traffic Safety Engineer

Arizona ITS Conference October 20, 2022

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2019 Arizona STSP

Toward Zero Deaths by Reducing Crashes for a Safer Arizona

In 2018 there were 1011 traffic related deaths on Arizona’s roadways

Reduce Traffic Fatalities on Arizona’s Roadways

VISION

CURRENT STATUS

GOAL

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2021 Fatality Update

1180 Fatalities

12% increase over 2020

Highest number since 2006

257 Pedestrian (Record High)

711 Lane Departure

296 Intersection Fatalities

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What Now?

Will things go back to pre-Pandemic normal?

  • Pandemic long-term effects?
  • Changes in work and travel patterns?
  • Changes in road use?

Do we want pre-Pandemic normal?

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Is 1000 deaths a year acceptable?

Annual Traffic Fatalities on All Arizona Roads

Can you imagine our state as a place where nobody dies in vehicle crashes?

How do we get there from here?

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The Safe System Approach

A new systemic approach aims to eliminate fatal and serious injuries for all road users by:

Accommodating human mistakes

Keeping impacts on the human body at tolerable levels

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Presentation Overview

1

Introduction

2

Safe System Principles

3

Safe System Elements

4

Case Studies

5

Conclusion & Next Steps

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The Safe System Approach

What is it?

  • Resilience
    • Building systems for the known characteristics of the known users
    • Moving from NOMINAL to SUBSTANTIVE safety
  • Forgiveness
    • Building systems that reduce the consequences of mistakes
  • Change

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  • 6 Principles
  • 5 Elements
  • 1 Goal:
    • 0 Deaths and Serious Injuries

THE SAFE SYSTEM APPROACH

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  • Death/serious injury is unacceptable
  • Humans make mistakes
  • Humans are vulnerable
  • Responsibility is shared
  • Safety is proactive
  • Redundancy is crucial

THE 6 SAFE SYSTEM PRINCIPLES

Source: FHWA

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  • Safe road users
  • Safe vehicles
  • Safe speeds
  • Safe roads
  • Post-crash care

THE 5 SAFE SYSTEM ELEMENTS

Source: FHWA

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SUCCESSFUL SAFE SYSTEM ADOPTERS

Sweden

Vision Zero

60-70% Reduction in fatalities 1994-2015

Netherlands

Sustainable Safety

50-60% Reduction in fatalities 1994-2015

Australia

Safe System

50-60% Reduction in fatalities 1994-2015

New Zealand

Safer Journeys

50-60% Reduction in fatalities 1994-2015

Source: World Resources Institute

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SAFE SYSTEM IN THE UNITED STATES

Early Adopters

  • California
  • Washington State
  • Florida
  • Portland, OR
  • Philadelphia, PA

Safe System still too new (in US) to see results

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Safe System Principles

Overview of the 6 principles of the Safe System approach

1

Introduction

2

Safe System Principles

3

Safe System Elements

4

Case Studies

5

Conclusion & Next Steps

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THE 6 SAFE SYSTEM PRINCIPLES

Death/serious injury is unacceptable

Humans make mistakes

Humans are vulnerable

Responsibility is shared

Safety is proactive

Redundancy�is crucial

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DEATH/SERIOUS INJURY IS UNACCEPTABLE

Source: Vision Zero Network

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HUMANS MAKE MISTAKES

Source: Fehr & Peers

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Crash Kinetic Energy

Source: FHWA

HUMANS ARE VULNERABLE

Serious Injury

Fatality

100%

0%

Fatality Risk

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RESPONSIBILITY IS SHARED

System managers

Planners, designers, builders, operators,�maintenance workers

Vehicle manufacturers

Law enforcement personnel

Post-crash personnel

System users

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SAFETY IS PROACTIVE

Identify risks

Mitigate risks

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REDUNDANCY IS CRUCIAL

Safe road users

Safe vehicles

Safe speeds

Safe roads

Post-crash care

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Safe System Elements

Overview of the 5 elements of the Safe System approach

1

Introduction

2

Safe System Principles

3

Safe System Elements

4

Case Studies

5

Conclusion & Next Steps

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THE 5 SAFE SYSTEM ELEMENTS

Safe road users

Safe vehicles

Safe speeds

Safe roads

Post-crash care

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SAFE ROAD USERS - RESPONSIBILITY

Walk

Bike

Drive

Transit

Accessible

Road use (by any mode) is one of the most dangerous things people each day

The Safe System Approach relies on people understanding this

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SAFE ROAD USERS - ENFORCEMENT

Not distracted or impaired

Follow rules (including safety equipment)

Act within the limits of the road design

Source: ADOT

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SAFE VEHICLES

Active safety

Measures to reduce the chance of a crash occurring

  • Lane departure warning
  • Autonomous emergency braking
  • Bicycle and pedestrian detection

Passive safety

Protective systems for when crashes do occur

  • Seatbelts, airbags and helmets
  • Crash-absorbing vehicle crumple zones
  • Vehicle size and design

New technology

Leveraging connected and automated vehicle (CAV) technology to improve safety

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SAFE SPEEDS

“Speed is at the heart of a forgiving road transport system. It transcends all aspects of safety: without speed there can be no movement, but with speed comes kinetic energy and with kinetic energy and human error come crashes, injuries, and even deaths.”

Differential

Organisation for Economic Co-operation and Development

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SAFE ROADS: AVOIDING CRASHES

Avoiding crashes involves:

Separating users in space

Separating users in time

Increasing attentiveness and awareness

Source for all images: Fehr & Peers

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SAFE ROADS: CRASH KINETIC ENERGY

Managing crash kinetic energy involves:

Managing speed

Source: ADOT

Manipulating mass

Source: Pinal Central

Manipulating crash angles

Source: City of Tempe, AZ

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POST-CRASH CARE

Vital post-crash actions include:

First responders

Medical care

Crash investigation

Traffic incident management

Justice

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THE 5 SAFE SYSTEM ELEMENTS CREATE REDUNDANCY

The “Swiss Cheese Model” of redundancy creates layers of protection

Death and serious injuries only happen when all layers fail

Post-crash care

Safe roads

Safe speeds

Safe vehicles

Safe road users

Post-crash care

Safe roads

Safe speeds

Safe vehicles

Safe road users

Source: FHWA

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Case Studies

Examples of the Safe System approach in the United States

1

Introduction

2

Safe System Principles

3

Safe System Elements

4

Case Studies

5

Conclusion & Next Steps

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PROTECTED BIKE LANES: PHOENIX, AZ

Safe System Elements Covered

Source: City of Phoenix, AZ

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US-60 AT I-10 MARICOPA COUNTY, AZ

Safe System Elements Covered

Source: ADOT

  • Installed: July 2018
  • Preliminary Results: Crashes reduced by 2/3
  • Solution: Second lane added to eastbound I-10 exit
  • Required modelling and design exception

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Conclusion & Next Steps

Starting the Journey

1

Introduction

2

Safe System Principles

3

Safe System Elements

4

Case Studies

5

Conclusion & Next Steps

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Safety Culture

The Safe System Approach requires a change in Safety Culture within many organizations.

Safety culture the shared values, actions, and behaviors that demonstrate a commitment to safety over competing goals and demands. This includes both within the organization (ADOT) and within the public.

The good news is that Safety Culture is reflected in the ADOT True North: SAFELY HOME

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Project Example

US-93 Road Widening Project

Nominal

  • MUTCD
  • Arizona RDG
    • Roadway Design Guidelines

Substantive

  • Safe System Approach
  • Performance Based Practical Design

Budget Constraints

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Opportunities

The Times They are a-Changin’ - Bob Dylan

  • Traffic patterns
    • Work from home and IOT may erode traditional traffic patterns
    • Capacity versus demand
  • Roadway users
    • Who is typical road user?
  • Public expectations
    • Greater awareness of traffic complexities
    • How long will public put up with existing crash numbers?

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Where We Go from Here

  • Develop implementation strategy
    • What are upper limits of Substantive Safety?
    • How much will it cost?
  • Establish performance measures
    • How will we know if it is working?
  • Adopt the Safe System Approach
    • 2024 Arizona Strategic Traffic Safety Plan (STSP) update
  • Integrate into standard work

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2024 Arizona Strategic Traffic Safety Plan

The Safe System Approach to be included in 2024 plan. But what does that mean?

  • What do we design and build to when we go beyond standards?
  • How do we justify increased costs?
  • How do we keep the Safe System a meaningful guiding philosophy?

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Traffic Safety Starts at and Ends at Home,�Drive, bike and walk safely!

Questions?

Kerry Wilcoxon, P.E., P.T.O.E., RSP1

State Traffic Safety Engineer

Arizona Department of Transportation kwilcoxon@azdot.gov�602-712-2060

Safe System Materials

Find more resources at: safety.fhwa.dot.gov/zerodeaths