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From page 261... ... Accessible Pedestrian Signals: A Guide to Best Practice C- 261 Appendix C: Research on APS Introduction Th roughout the preceding chapters of this Guide, references were made to various studies to support the recommendations given in those chapters. Interested readers may wish to see more details on the studies underlying these recommendations. Read the entire page →
From page 262... ... C - 262 Appendix C: Research on APS Research on problems of blind pedestrians INTRODUCTION Although APS have been widely used in Japan and Sweden since the 1960s, the early development of APS in those countries was not, as far as these authors have been able to ascertain, based on research. Nor was there any research basis for the "cuckoo/ cheep" APS that has been most commonly used in the U.S. Read the entire page →
From page 263... ... Accessible Pedestrian Signals: A Guide to Best Practice C- 263 In 1998, the American Council of the Blind (ACB) and the Association for Education and Rehabilitation of the Blind and Visually Impaired (AER) Read the entire page →
From page 264... ... C - 264 Appendix C: Research on APS obtained at two complex, signalized intersections in each city. Measures were similar to those used in the SKERI research, including nine broad measures of crossing timing, orientation, and independence. Read the entire page →
From page 265... ... Accessible Pedestrian Signals: A Guide to Best Practice C- 265 of the direction of the destination corner is the direction pedestrians are traveling before they arrive at the starting corner. Additional cues that are useful in familiar locations are walls, fences, hedges, grasslines, and objects near the curb that have a straight surface that is either parallel or perpendicular to the direction of travel across the crosswalk. Read the entire page →
From page 266... ... C - 266 Appendix C: Research on APS pushes the button, the WALK signal will not come on, and, when there is a green signal for parallel traﬃ c, it is timed to accommodate vehicular traﬃ c, not pedestrians. A pedestrian who does not push the button, and who crosses with the green signal for parallel traﬃ c, may not have enough time to cross the street. Read the entire page →
From page 267... ... Accessible Pedestrian Signals: A Guide to Best Practice C- 267 interval is not in eﬀ ect. Complex geometry and intersection signalization make the use of traditional clues to the onset of the WALK interval unreliable. Read the entire page →
From page 268... ... C - 268 Appendix C: Research on APS were problems both with APS being considered too quiet and too loud. 45% of participants in ACB survey considered signals to be too loud while 71% considered them too quiet. Read the entire page →
From page 269... ... Accessible Pedestrian Signals: A Guide to Best Practice C- 269 Pedestrian crashes To obtain a rough measure of the incidence of intersection crashes and near crashes for pedestrians who are visually impaired, the ACB survey asked respondents whether they had been struck by a car at an intersection, and whether they had had their long canes run over. In the ACB survey, 12 of 158 (8%) Read the entire page →
From page 270... ... C - 270 Appendix C: Research on APS Effects of APS on specifi c crossing tasks INTRODUCTION Since it is known that pedestrians with visual impairments have diﬃ culty with many of the tasks that, taken together, comprise street crossing, it would be desirable to think that APS improve all measures of crossing at signalized intersections. To determine the extent to which this is true, a number of research projects have obtained objective data comparing street crossing with and without APS on one or more of the following measures. Read the entire page →
From page 271... ... Accessible Pedestrian Signals: A Guide to Best Practice C- 271 RESULTS OF RESEARCH Locating the crosswalk SKERI research found that starting crossing from within the crosswalk increased from 70% to 97% with use of the APS. NEI Portland pre-post research found signiﬁ cant increases in participants' ability to begin crossings from within the crosswalk at locations where pushbutton use was required, and pushbutton locator tones were installed. Read the entire page →
From page 272... ... C - 272 Appendix C: Research on APS Using pushbuttons Data reported in NEI pre-APS installation testing (NEI-2 cities, NEI-3 cities) indicated that blind pedestrians typically didn't search for and use pedestrian pushbuttons at unfamiliar intersections. Read the entire page →
From page 273... ... Accessible Pedestrian Signals: A Guide to Best Practice C- 273 • For pedestrians who arrived at the crossing during the ﬂ ashing or steady DONT WALK and who waited to cross until the onset of the WALK interval, the proportion who failed to complete their crossings before the onset of opposing traﬃ c was reduced by one-half, from 22% to 11%. Williams et al. Read the entire page →
From page 274... ... C - 274 Appendix C: Research on APS WALK interval, unless the pushbutton was pushed again. Pre-installation, 70% of independent crossings began during the WALK interval; post-installation, this increased to 100%. Read the entire page →
From page 275... ... Accessible Pedestrian Signals: A Guide to Best Practice C- 275 Effect of APS on independence and confi dence Both independence and conﬁ dence aﬀ ect the likelihood that people who are blind will cross streets independently. Lack of independence and low conﬁ dence in ability to cross safely result in lack of participation in normal community life. Read the entire page →
From page 276... ... C - 276 Appendix C: Research on APS Effects of WALK signal characteristics INTRODUCTION Access Board Draft Guidelines for Accessible Public Rights-of-Way (revised 2005) and this APS Guide recommend using a rapid tick WALK indication. Read the entire page →
From page 277... ... Accessible Pedestrian Signals: A Guide to Best Practice C- 277 Upper frequency hearing loss results in a decrease in the ability to localize sound and to understand speech, particularly in noisy environments (Wiener & Lawson, 1997) Read the entire page →
From page 278... ... C - 278 Appendix C: Research on APS traﬃ c noise for subjects with age related hearing loss. Signals evaluated were an 880Hz square wave, a bird chirp, a cuckoo, two click trains, two percussive signals ("bink" and "tok") Read the entire page →
From page 279... ... Accessible Pedestrian Signals: A Guide to Best Practice C- 279 or from a speaker at the pedestrian signal head. APS with speech messages are considered by many people to be especially user-friendly, when demonstrations are given indoors, to an audience for whom English is the predominant ﬁ rst language. Read the entire page →
From page 280... ... C - 280 Appendix C: Research on APS Eﬀ ect of Speech Messages on all pedestrians Van Houten, Malenfant, Van Houten and Retting (1997) found that redundant information conveyed by audible pedestrian signals increases the attention of all pedestrians to turning traﬃ c and may contribute to a reduction in pedestrianvehicular conﬂ icts and crashes at signalized intersections. Read the entire page →
From page 281... ... Accessible Pedestrian Signals: A Guide to Best Practice C- 281 Accuracy and speed in identifying WALK indication for a given crossing INTRODUCTION Access Board Draft PROWAG and the APS Guide emphasize the importance of installation location for APS. Installation location is critical for accurate and fast identiﬁ cation of which crosswalk has the WALK signal. Read the entire page →
From page 282... ... C - 282 Appendix C: Research on APS Th e above graphic illustrates the recommended placement of APS devices in relation to the crosswalk provided in the APS Synthesis in 2003. Th is arrangement was based on the NEI research described above. Read the entire page →
From page 283... ... Accessible Pedestrian Signals: A Guide to Best Practice C- 283 Results indicated that where pushbutton-integrated APS were mounted on separate poles, near the crosswalk line furthest from the center of the intersection, approximately 3 feet from the curb line, and approximately 10 feet apart, accuracy in judging when the correct crosswalk had the WALK signal was signiﬁ cantly better than when APS were located according to other criteria (see corner C, Figure C-3) Read the entire page →
From page 284... ... C - 284 Appendix C: Research on APS than variation in WALK indications. Th e research recommended use of the rapid tick WALK indication because it produced the fastest and most accurate responses regarding which crosswalk has the WALK indication. Read the entire page →
From page 285... ... Accessible Pedestrian Signals: A Guide to Best Practice C- 285 Research on source of WALK signal INTRODUCTION Signals that have been typically installed in the U.S. have provided a loud beaconing WALK indication simultaneously from both ends of the crosswalk, and usually from two parallel crosswalks at the same time. Read the entire page →
From page 286... ... C - 286 Appendix C: Research on APS Wall et al. Read the entire page →
From page 287... ... Accessible Pedestrian Signals: A Guide to Best Practice C- 287 Research on other APS Features Previously described research has also looked at other speciﬁ c features of APS including the pushbutton locator tone. Th e following sources are referred to: NCHRP 3-62 research, Barlow et al. Read the entire page →
From page 288... ... C - 288 Appendix C: Research on APS than smaller, non-graspable, arrows and those mounted on the vertical face of the APS. Th e failure to ﬁ nd any positive eﬀ ect on alignment indicates that such an arrow (or probably any arrow) Read the entire page →
From page 289... ... Accessible Pedestrian Signals: A Guide to Best Practice C- 289 have the potential to enable users who are unfamiliar with a particular crosswalk to anticipate such characteristics as the number of vehicular lanes in each direction, and the presence of islands or medians, rail tracks, and bicycle lanes. In NCHRP 3-62 research (see and Bentzen et al., in press) Read the entire page →
From page 290... ... C - 290 Appendix C: Research on APS In NCHRP 3-62 research (NCHRP 3-62, Final Report, Chapter 3; Bentzen et al, in press) the extended button press feature was included on three of four types of APS. Read the entire page →
From page 291... ... Accessible Pedestrian Signals: A Guide to Best Practice C- 291 Other concerns and needs ENGINEERING CONCERNS Noyce & Barlow (2003) investigated problems reported with the interface between APS devices and signal controllers to determine whether there were systemic problems with the APS/controller interface. Read the entire page →
From page 292... ... C - 292 Appendix C: Research on APS Th e major reason for the tactile arrow is to enable users to identify which street the pushbutton controls. Many participants in NCHRP 3-62 research and in NEI research needed to be shown the arrows on the devices to understand which way the arrow pointed. Read the entire page →
From page 293... ... Accessible Pedestrian Signals: A Guide to Best Practice C- 293 Need for additional research At a meeting in September, 2005, the project panel for NCHRP 3-62 developed the following list of issues for additional research: • Guidance on the need for pushbutton APS on side streets. • Wayﬁ nding/beaconing (NEI project may address this need) Read the entire page →
From page 294... ... C - 294 Appendix C: Research on APS References Adams, P.F., Hendershot, G.E., and Marano, M.A. Current estimates from the National Health Interview Survey, 1996. Read the entire page →
From page 295... ... Accessible Pedestrian Signals: A Guide to Best Practice C- 295 Brabyn, J.A., Haegerström-Portnoy, G, Schneck, M.E., and Lott, L.A. Visual impairments in elderly people under everyday viewing conditions. Read the entire page →
From page 296... ... C - 296 Appendix C: Research on APS Hulscher, F Read the entire page →
From page 297... ... Accessible Pedestrian Signals: A Guide to Best Practice C- 297 San Diego Association of Governments. Read the entire page →
From page 298... ... C - 298 Appendix C: Research on APS Van Houten, R., Malenfant, J., Van Houten, J & Retting, R Read the entire page →

From page 261...

... Accessible Pedestrian Signals: A Guide to Best Practice C- 261 Appendix C: Research on APS Introduction Th roughout the preceding chapters of this Guide, references were made to various studies to support the recommendations given in those chapters. Interested readers may wish to see more details on the studies underlying these recommendations.