Pedestrians who are blind at Roundabouts

1. Pedestrians who are blindat Roundabouts Janet Barlow, COMS Accessible Design for the Blind FHWA Webinar August 13, 2010

2. Transportation choices for individuals who are blind or who have low vision • Walk • Public transit - Bus or rail • Paratransit services • Taxis or shuttles • Rides from friends or relatives • Paid drivers Accessible Design for the Blind, 8/13/2010, Slide

3. Pedestrians with low vision (many of our growing elderly population) • May have difficulty with depth perception • Problems in judging location of vehicles • Problems in judging approach speed of vehicles • May have reduced contrast sensitivity Accessible Design for the Blind, 8/13/2010, Slide

4. Travel in unfamiliar locations • Pedestrians who are blind or visually impaired in the US do travel to new locations or intersections and ‘figure them out’ by listening and exploring Accessible Design for the Blind, 8/13/2010, Slide

5. Aids and techniques for obstacle and curb detection • Long white cane • Used as a probe of the walking surface • May identify person as visually impaired Accessible Design for the Blind, 8/13/2010, Slide

6. Aids and techniques for obstacle and curb detection • Dog guide • Guides around obstacles • Stops at curbs or drop-offs • Low vision aid, such as telescope • Used only for specific tasks, ie reading sign Accessible Design for the Blind, 8/13/2010, Slide

7. Orientation and alignment cues • Slight slopes and changes in surface textures • Sidewalk and/or grass line or building line • Traffic – both parallel to travel path and perpendicular to travel path • Other pedestrians, sun, other cues • Awareness of intersecting streets and general layout of area Accessible Design for the Blind, 8/13/2010, Slide

8. Crossing cues • Signalized • Traffic stopping on the street that the pedestrian is planning to cross • Vehicles starting and moving across the intersection in the closest through lane • Unsignalized • Hearing a vehicle approaching • Not hearing any vehicles • Hearing a vehicle yielding • Traffic moving parallel to crosswalk Accessible Design for the Blind, 8/13/2010, Slide

9. Wayfinding issues • Recognizing that the intersection is a roundabout • Locating crosswalks • Aligning to cross Accessible Design for the Blind, 8/13/2010, Slide

10. Locating crosswalks Where blind pedestrian might cross (if unaware that’s it’s a roundabout) Accessible Design for the Blind, 8/13/2010, Slide

11. Finding proper crossing location Have to turn before intersection Crosswalk Accessible Design for the Blind, 8/13/2010, Slide

12. Finding proper crossing location Or continue around the corner Accessible Design for the Blind, 8/13/2010, Slide

13. Wide curb ramp may be mistaken for driveway; also wider than crosswalk Accessible Design for the Blind, 8/13/2010, Slide

14. Landscaping could have been used to guide person to crosswalk and to help them align to cross Accessible Design for the Blind, 8/13/2010, Slide

15. Potential treatments – wayfinding • Design of sidewalk • Tactile features or fences • Sound cues from audible signals Accessible Design for the Blind, 8/13/2010, Slide

16. Issues with determining when to cross • Detecting a gap in traffic • Detecting that vehicle has yielded • For pedestrians who are blind, research has documented • latency and delay in detecting gap or yield, and subsequent inability to cross • unsafe judgments about gaps or yields Accessible Design for the Blind, 8/13/2010, Slide

17. Detecting a gap, or yield • Using hearing alone, it is not always possible to pinpoint direction of sound • not as specific as vision • cannot select just one lane or area to check • One vehicle can mask the sound of others approaching, possibly closer • Quieter cars further complicate this problem Accessible Design for the Blind, 8/13/2010, Slide

18. Latency and delay in detecting gaps Accessible Design for the Blind, 8/13/2010, Slide

19. Sound masking • Vehicles that have just passed the crosswalk • Vehicles in the circulatory roadway • Vehicles approaching in other lane of the street the pedestrian is crossing (behind of or in front the splitter island) • Vehicles that stop to allow the pedestrian to cross (multi-lane roundabout) mask sound of vehicles approaching in other lane Accessible Design for the Blind, 8/13/2010, Slide

20. Sound masking • Vehicles on nearby bridges/expressways • Other sounds in the environment • Lawnmowers • Nearby construction • High ambient noise Accessible Design for the Blind, 8/13/2010, Slide

21. Pedestrian who is blind cannot safely assume that drivers will yield Accessible Design for the Blind, 8/13/2010, Slide

22. Driver yielding behavior • NEI research – Maryland roundabout • Likelihood of yielding diminishes with increasing speed • White cane has only modest impact on yielding behavior • At one location, drivers yielded 79% of the time for the entry lanes, but only 37% of the time for the exit lanes • FHWA research – 11.5% of vehicles yielded • NCHRP 3-78 research – several locations - yielding rates varied • Single lane roundabouts - entry – rates ranged from 10.8% to 65.6% • Single lane roundabouts - exit - rates ranged from 11.8% to 36.1%’ • Multilane roundabout - average yielding in both lanes, without treatment, ranged from 25.2%  to 29.7% • (Geruschat, D.R., & Hassan, S.E. (2005). Driver behavior in yielding to sighted and blind pedestrians at roundabouts. Journal of Visual Impairment and Blindness; National Cooperative Highway Research Program. NCHRP 3-78a. Draft Final Report; Crossing Solutions at Roundabouts and Channelized Turn Lanes for Pedestrians with Vision Disabilities; Inman, V. W., Davis, G. W., & Sauerburger, D. (2005). Pedestrian access to roundabouts: Assessment of motorist yielding to visually impaired pedestrians and potential treatments to improve access) Accessible Design for the Blind, 8/13/2010, Slide

23. Blind pedestrians often did not detect vehicles yielding • NEI research – Nashville roundabout • Sighted participants took advantage of all 12 yields they were offered • Blind participants crossed on only 9 of the 37 yields they were offered • Sometimes crossed without knowing a vehicle was there • Sometimes perceived the yield but didn’t know about other vehicles • Drivers frustrated / irritated when blind participants did not take the yield (Guth, D., Ashmead, D., Long, R., Wall, R., & Ponchillia, R. (2005). Blind and sighted pedestrians’ judgments in gaps in traffic at roundabouts. Human Factors, 47, 314–331.) Accessible Design for the Blind, 8/13/2010, Slide

24. NCHRP 3-78a Research Study Design • Pre-post within-subject with treatment installation • Orientation and Mobility (O&M) familiarization and supervision throughout trials • Independent crossings (with O&M) • Blind participants could stop participation at any time Accessible Design for the Blind, 8/13/2010, Slide

25. Evaluation of Single-Lane Roundabouts • Three sites tested • Three different cities • No treatments installed • Varying geometries • Range of volumes • Different participants and driving culture Accessible Design for the Blind, 8/13/2010, Slide

26. Single-Lane Roundabout Results • Tested single-lane roundabouts appear to not pose unreasonable crossing difficulties to most blind travelers, provided that • Speeds are low through good roundabout design • Drivers are courteous and yield the right-of-way • Appropriate detectable warnings are installed • Blind travelers receive orientation and mobility instruction specific to roundabout crossings Accessible Design for the Blind, 8/13/2010, Slide

27. Two-Lane RoundaboutGolden Rd. @ Johnson Rd., Golden, CO Accessible Design for the Blind, 8/13/2010, Slide

28. Two treatments • Raised crosswalk • Pedestrian Hybrid Beacon (previously called HAWK) Accessible Design for the Blind, 8/13/2010, Slide

29. Raised Crosswalk Accessible Design for the Blind, 8/13/2010, Slide

30. Pedestrian Hybrid Beacon Accessible Design for the Blind, 8/13/2010, Slide

31. Two-Lane RBT Findings • Two-lane roundabouts are challenging without additional treatments • Speed and volumes are higher • Multiple-threat situations are biggest risk • Treatments proved effective in reducing speeds, increasing yields, and creating crossing opportunities • Treatments reduced delay and interventions (risk) • Raised crosswalk exhibited more multiple threat and (perceived) risk than PHB Accessible Design for the Blind, 8/13/2010, Slide

32. The NCHRP 3-78a Final Report • … establishes common “language” and performance measures for ongoing accessibility debate • … contains field data for twelve studies at five intersections, 56 blind participants, and 3300 crossing attempts • … presents an initial assessment of new crossing treatments, particularly for two-lane roundabouts • … provides ways to extend the research results through statistical modeling and simulation • … establishes a baseline for future research in this area to assure compatibility of results • The report does not give warrants or requirements for treatment installation Accessible Design for the Blind, 8/13/2010, Slide

33. Research status • NCHRP 3-78a completed; final report available when NCHRP publishes it • FHWA research completed in 2006; report available online (Inman, Davis, Sauerburger) • Several articles published on NEI research; research is continuing • Testing treatments at 3-lane roundabouts in Michigan (with financial assistance from Oakland County) • Quiet car issues • Wayfinding issues Accessible Design for the Blind, 8/13/2010, Slide

34. Research Needs • Additional treatment testing at two-lane roundabouts to increase sample size and build confidence in treatment effectiveness • Supplemental data for single-lane roundabouts to understand relationship of design and traffic volumes to accessibility • Development of improved measures to quantify pedestrian risk Accessible Design for the Blind, 8/13/2010, Slide

35. More information • www.itre.ncsu.edu/ITRE/research/Pedestrian-Accessibility/index.html • www.tfhrc.gov/safety/pedbike/pubs/05080/ • www.accessforblind.org • jmbarlow@accessforblind.org Accessible Design for the Blind, 8/13/2010, Slide