Annual Meeting of the AASHTO Subcommittee on Design

Annual Meeting of the AASHTO Subcommittee on Design Human Factors Guidelines (HFG) for Road Systems (NCHRP 17 -41) July 22, 2009 John L. Campbell Battelle, Center for Human Performance and Safety BUSINESS SENSITIVE 1

Discussion Topics • Project Overview • Conceptual Framework for Guideline Development • Progress To Date • Current Activities • Next Steps BUSINESS SENSITIVE 2

Project Overview • Title: Human Factors Design Guidelines (HFG) for Road Systems – Phase II, NCHRP 17 -31, July 2005 – July 2008 – Phase III, NCHRP 17 -41, March 2008 – February 2010 • Phase I (NCHRP 17 -18 (8), 2001 -2004): Key products were introductory HFG materials and guidelines for Sight Distance • Sponsor/COTR: TRB/Chuck Niessner BUSINESS SENSITIVE 3

Project Overview Why do we need Human Factors Guidelines for Road Systems? • Existing references for road system design do not always provide highway designers and traffic engineers with adequate guidance for incorporating road user needs, limitations, and capabilities. • Considerable research exists on road users’ characteristics that is not included in existing reference materials. • Designers and engineers value and will use factual information and insights on road users’ characteristics to facilitate safe roadway design and operational decisions. BUSINESS SENSITIVE 4

Project Overview Why do we need Human Factors Guidelines for Road Systems? • The HFG is intended to complement, not replace, existing sources of road design information. BUSINESS SENSITIVE 5

Project Overview Specific Requirements for the HFG The Human Factors Guidelines should: • Reflect user requirements for content, format, and organization • Focus on road user needs, limitations, and capabilities • Provide clear, relevant, and easy-to-use guidance • Aid and augment the judgment and experience of highway designers and traffic engineers BUSINESS SENSITIVE 6

Conceptual Framework for Guideline Development Original Research Compilations EXPERIMENTS Journal Articles Conference Proceedings Books Literature Reviews Handbooks Technical Reports User-Centered Guidelines System Designer needs for content, organization, and format Design Environment Formulation of Individual Guidelines • Objectives & Tasks • • • Available Design Dat Design Process Existing Constraints “Givens” in Design Diverse Designers Standards Database of Human Factors Research Integrative review of data sources FINAL DESIGN SPECIFICATIONS BUSINESS SENSITIVE 7

Progress To Date Procedures for Guideline Development 1 Identify User Needs Human Factors Literature 2 3 4 Select Data Sources Design Context Key Data Sources Representative End-Users Evaluate the Selected Data Sources Formulate the Guidelines Reviews of Draft Guidelines BUSINESS SENSITIVE 8

Progress To Date Overview of Current HFG Contents PART I: INTRODUCTION TO THE HUMAN FACTORS GUIDELINES Chapter 1: Why Have Human Factors Guidelines (HFG) for Road Systems? Chapter 2: How to Use this Document PART II: BRINGING ROAD USER CAPABILITIES INTO HIGHWAY DESIGN AND TRAFFIC ENGINEERING PRACTICE Chapter 3: Finding Information Like a Road User Chapter 4: Integrating Road User, Highway Design, and Traffic Engineering Needs BUSINESS SENSITIVE 9

Progress To Date Overview of Current HFG Contents PART III: HUMAN FACTORS GUIDANCE FOR ROADWAY LOCATION ELEMENTS Chapter 5: Sight Distance Guidelines (8) Chapter 6: Curves (Horizontal) (6) Chapter 10: Non-signalized Intersections (5) Chapter 11: Signalized Intersections (4) Chapter 13: Construction and Work Zones (6) BUSINESS SENSITIVE 10

Progress To Date Overview of HFG Contents PART V: ADDITIONAL INFORMATION Chapter 22: Tutorials – Tutorial 1: Real-World Driver Behavior Versus Design Models – Tutorial 2: Diagnosing Sight Distance Problems and Other Design Deficiencies Chapter 23: References BUSINESS SENSITIVE 11

Progress To Date Presentation Format Abbreviated Chapter Title Revision Handbook Title Guideline Title Version Bar Scale Rating (Both Pages) Introduction (Both Pages) Discussion Design Guideline Design Issues Figure, Table, or Graphic Cross References Left-hand page Page Numbers Right-hand page BUSINESS SENSITIVE 12

Progress To Date Examples of Guidelines/Graphics Key Components of Sight Distance BUSINESS SENSITIVE 13

Progress To Date Examples of Guidelines/Graphics Acceptable Gap Distance Time Gap (tg) (seconds) at design speed of major road Design Vehicle Left Turn Right Turn Passenger car 7. 5 6. 5 Single-unit truck 9. 5 8. 5 Combination truck 11. 5 10. 5 BUSINESS SENSITIVE 14

Progress To Date Examples of Guidelines/Graphics Countermeasures for Improving Accessibility of Vision-impaired Pedestrians at Roundabouts BUSINESS SENSITIVE 15

Progress To Date Examples of Guidelines/Graphics Task Analysis of Curve Driving BUSINESS SENSITIVE 16

Progress To Date Examples of Guidelines/Graphics The Influence of Perceptual Factors on Curve Driving BUSINESS SENSITIVE 17

Current Activities • Chapters currently under development in Phase III of the HFG effort: – Chapter 16: Special Considerations for Rural Environments – Chapter 17: Speed Perception, Speed Choice, and Speed Control – Chapter 18: Signing – Chapter 19: Changeable Message Signs – Chapter 20: Markings BUSINESS SENSITIVE 18

For More Information… • NCHRP Report 600 B – http: //www. trb. org/news/blurb_detail. asp? id=9867 • Project 17 -41 website – http: //www. trb. org/TRBNet/Project. Display. asp? Pro ject. ID=1635 • John L. Campbell, Battelle – 206 -528 -3254 – campjohn@battelle. org • Chuck Niessner, NAS/NCHRP – 202 -334 -1431 – CNiessner@nas. edu BUSINESS SENSITIVE 19