The increasing number of hybrid and quiet internal combustion engine vehicles may impact the travel abilities of pedestrians who are blind. Pedestrians who rely on auditory cues for structuring their travel may face challenges in making crossing decisions in the presence of quiet vehicles. This article describes results of initial studies looking at the crossing decisions of pedestrians who are blind at an uncontrolled crossing (no traffic control) and a light controlled intersection. The presence of hybrid vehicles was a factor in each situation. At the uncontrolled crossing, Toyota hybrids were most difficult to detect but crossing decisions were made more often in small gaps ended by a Honda hybrid. These effects were seen only at speed under 20 mph. At the light controlled intersection, parallel surges of traffic were most difficult to detect when made up only of a Ford Escape hybrid. Results suggest that more controlled studies of vehicle characteristics impacting crossing decisions of pedestrians who are blind are warranted. Keywordsblind; hybrid; visually impaired; pedestrian; crossing; gap IntroductionIn 2004, National Health Interview Survey (NHIS) data revealed prevalence rates of visual impairment of 8.8% or 19.1 million (Lethbridge-Cejku, Rose & Vickerie, 2006). The Eye Diseases Prevalence Research Group (2004) estimates a 70% increase in [legal] blindness as well as in low vision by 2020. Given such numbers, it is fair to assume that a significant portion of this population is accessing public sidewalks and thoroughfares as pedestrians. In doing so, there is a certain probability that a pedestrian with a visual impairment will come into conflict with an automobile. This probability increases as pedestrians with visual impairments encounter increasingly complex traffic situations (e.g., roundabouts) or have limited access to important orientation information (e.g., the sound of an approaching vehicle) (Ashmead, Guth, Wall, Long & Ponchillia, 2005;Barlow, Bentzen & Bond, 2005).Corresponding author: Dr. Robert Wall Emerson, robert.wall@wmich.edu. Publisher's Disclaimer: This is a PDF file of an unedited manuscript that has been accepted for publication. As a service to our customers we are providing this early version of the manuscript. The manuscript will undergo copyediting, typesetting, and review of the resulting proof before it is published in its final citable form. Please note that during the production process errors may be discovered which could affect the content, and all legal disclaimers that apply to the journal pertain. NIH Public Access Author Manuscript NIH-PA Author ManuscriptNIH-PA Author Manuscript NIH-PA Author ManuscriptThere is a fear that increasingly quiet vehicles on the road will increase pedestrian-vehicle conflicts in the near future (e.g., TheGreenCarWebsite.co.uk, September, 2008) prompting calls for research and legislative action (Wunder, 2008).Epidemiological research on pedestrian safety during the past decade (Campbell, Zegeer, Huang & Cynecki, 2004; Natio...