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                        Handbook for Designing Roadways for the Aging Population


            
            In This Section
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                Part II. Rationale and Supporting Evidence
Overview

This section of the *Handbook* is organized in terms of the same category of highway features as the treatments:

Chapter 7 – Intersections,
	Chapter 8 – Interchanges,
	Chapter 9 – Roadway Segments,
	Chapter 10 – Construction/Work Zones, and
	Chapter 11 – Highway-Rail Grade Crossings.Within each of these five chapters (category), subsections are organized in terms of design elements with unique geometric, operational, and/or traffic control characteristics, also consistent with the treatments. Also, the rationale for the additional "Promising Practices" treatments included under Intersections, Interchanges, Roadway Segments and Construction/Work Zones is presented at the end of their respective chapters.

At the beginning of each subsection within a class of highway features, reference material for a particular design element is introduced using a cross-reference table. This table relates the discussion in that subsection—as well as the associated treatments, presented earlier—to entries in standard reference manuals consulted by practitioners in this area. Principal among these reference manuals are the following:

*Manual on Uniform Traffic Control Devices*, Editions 2009 and 2003. (Note to reader: if the discussion refers to *MUTCD* material found in the revisions to 2003 published in 2007, the citation will be *MUTCD* 2003a.)
	*A Policy on Geometric Design of Highways and Streets* [the *Green Book*], 2011);
	*Traffic Engineering Handbook* (TEH, 2009).Other standard references with more restricted applicability, which also appear in the cross-reference tables for selected design elements, include the following:

*Intersection Channelization Design Guide*, NCHRP Report No. 279, (Neuman, 1985).
	*Roundabouts: An Informational Guide*, Second Edition, NCHRP Report 672, (Rodegerdts, et al., 2010).
	*Roundabouts: An Informational Guide* (FHWA, 2000).
	*Roadway Lighting Handbook* (FHWA, 1978).
	*Railroad-Highway Grade Crossing Handbook* (FHWA, 2007).
	*Highway Capacity Manual* (TRB, 2010).
	*A Guide for Reducing Collisions Involving Older Drivers*, NCHRP Report No. 500-Volume 9, (Potts et al, 2004).Material in this part of the *Handbook* represents, to as great an extent as possible at the time of its development, the results of empirical work with aging driver or pedestrian samples for investigations with the specific highway features of interest. Naturalistic and controlled field studies were given precedence, augmented by laboratory simulations employing traffic stimuli and relevant situational cues. Crash data are cited as appropriate. In addition, some citations reference studies showing effects of design changes, where the predicted impact on (aging) driver performance is tied logically to the results of research on age-related differences in detection, comprehension, response selection, maneuver execution, or other capability needed to safely negotiate the design element.
      
  Book traversal links for Part II. Rationale and Supporting Evidence
      ‹ Chapter 6. Highway-Rail Grade Crossing
                    Up
                    Chapter 7. Intersections ›
                
                Book:Handbook for Designing Roadways for the Aging Population
              Preface
                Acknowledgements
                Abbreviations and Acronyms
                Chapter 1. How to Use this Handbook
                Part I. Treatments
                Chapter 2. Intersections
                Chapter 3. Interchanges
                Chapter 4. Roadway Segments
                Chapter 5. Construction/Work Zones
                Chapter 6. Highway-Rail Grade Crossing
                Part II. Rationale and Supporting Evidence
                Chapter 7. Intersections
                Chapter 8. Interchanges
                Chapter 9. Roadway Segments
                Chapter 10. Construction/Work Zones
                Chapter 11. Highway-Rail Grade Crossings
                APPENDIX A
                APPENDIX B
                APPENDIX C
                APPENDIX D U.S. DEPARTMENT OF TRANSPORTATION

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