TRANSIT FACILITY DESIGN FOR PERSONS WITH VISUAL IMPAIRMENTS United States Architectural & Transportation Barriers Compliance Board 1111 Eighteenth Street, N. W. *Suite 501 Washington, D.C. 20236-3894 (202) 653-7834 [Voice or TDD] The Architectural and Transportation Barriers Compliance Board (Access Board) is charged with enforcing the Architectural Barriers Act of 1968 (42U.S.C. 4151), developing the Minimum Guidelines and Requirements for Accessible Design (MGRAD) for the standards under that act, and providing technical assistance for Title V of the Rehabilitation Act of 1973, as amended. In developing the minimum guidelines, and providing technical assistance on universal design, the Access Board sponsors research on various issues. The Access Board has not yet determined which, if any of the recommendations contained in this document will be incorporated in revisions to MGRAD as regulatory requirements. This pamphlet, provided to meet the Access Board's statutory mandate to provide technical assistance, contains selected recommendations from several research reports as advisory guidance. Most of the complete project reports (some have since gone out of print), which include descriptions of methodology and findings, can be obtained either from the Access Board or the National Technical Information Service, Springfield,Virginia. This document is disseminated under the sponsorship of the Access Board in the interest of information exchange. Neither the Access Board nor the United States Government assumes legal liability for its contents or use thereof. Several new and existing rapid rail transit (subway) systems have begun to take into account the needs of persons with various disabilities in their design and operation. Newer stations often include elevators for persons who have difficulty using stairs and escalators; elevators better serve persons with mobility disabilities. Some systems provide verbal announcements of stops. Some have provided telecommunication devices for deaf persons (TDDs) for customer information and communication; and some have provided visual displays of public address announcements. In general such improvements benefit all members of the general public. However, accidents on rapid transit platforms involving persons with visual impairments have raised concerns among architects, engineers and transit providers as to whether current design considerations are adequate. Clearly, the perception of blind and visually impaired persons as "helpless victims" of the environment is incorrect. Many people who are visually impaired or blind are quite capable of independent mobility and wayfinding with the aid of canes and guide dogs. The environment provides a variety of cues such as sidewalk edges, curbs, building walls, and sounds to allow people with limited vision to navigate. In addition, most people considered "blind" have some usable vision and can perceive light which, coupled with sound, permits them to judge traffic patterns, determine the location of open elevator and subway car doors, and avoid many obstacles. In fact, the primary means of accommodating individuals with all types of disabilities, including visual impairment, in rapid-rail transit systems is simply to apply the common principles of good design such as general illumination, adequate circulation space to reduce congestion, the placement of elements such as entrances, ticket machines, fare collection, boarding areas, etc. in a logical functional sequence, and adequate signage and information. the single most important factor in a given system is consistency in station design and layout. Consistent design does not necessarily mean identical design but a reasonable expectation on the part of a new transit rider that, having successfully used one station, the same elements can be found in similar locations in another. If public transportation is to attract significant numbers of new riders, with or without disabilities, everything that can possibly enhance orientation and wayfinding for those riders should be incorporated into the design. For individuals with visual impairments, the second most important factor is having good mobility skills. For all persons, wayfinding and mobility are learned skills and independent mobility varies greatly from person to person (everyone knows somebody who can get lost on his or her own block and somebody who can find his or her way around the most confusing city). Wayfinding and mobility can be enhanced by practice and formal training, particularly where environmental and personal circumstances change; and there are programs across the country specifically designed to improve the skills of persons with visual impairments. In the case of rapid transit, mobility and wayfinding skills are system-specific. For example, the average rider, with or without visual impairment, who learns to use the Washington, DC, Metro-rail system will not necessarily be able to apply that knowledge in using the New York subway system since the systems are dramatically different. Transit systems can help everyone by providing clear, concise information to the general public in a format also usable by persons with visual impairments, and by working with local mobility training centers to develop system-specific training programs. In the past several years, however, there have been increasing numbers of reports of persons with visual impairments falling from subway platforms, Explaining these accidents has been the focus of ongoing debate and discussion. Some people presume these accidents are due to poor mobility skills or the failure to apply them properly others feel the transit station design is at fault. Can Improved Mobility Training Solve the Problem? One well-documented case where a person who is blind fell to the tracks involved an individual with good mobility skills who was not only familiar with the system but had safely used that station on a daily basis before the accident. Such instances seem to imply that even those with relatively good mobility skills and familiarity with the environment can encounter difficulty. Mobility training alone may not be sufficient to prevent such accidents. The range of wayfinding abilities is as widely disparate among trainees as it is among others in the general population. In addition, many individuals with visual impairments do not have access to formal mobility training. For example, one of the largest segments of the visually impaired population consists of elderly people whose vision has gradually changed over time. These people may not realize they are "visually impaired." For others medication or illness may contribute to "night blindness" which is exacerbated by moving from daylight into a dimly lighted subway station. finally, there are large numbers of low-income people who, because of inadequate access to health care and other disability-related services, receive no mobility training. Yet the low-income segment of the population is the one most heavily dependent on public transportation. The Importance of Good Design A transportation agency must plan and design the safest system possible for people with and without good wayfinding and mobility skills, one consistent with overall operating constraints and maximum independent accessibility. As valuable as mobility training may be, it is not a "design feature" which can be put into place and maintained for the benefit of everyone, nor can it be incorporated in building codes or standards for accessible design. Designers must also recognize, however, that there is an element of risk for any person with or without a disability to participate in society and that risk can only be reduced, not completely eliminated, without denying that person the right to participate. Recognizing the importance of good design, the Access Board has sponsored several research projects to identify design features which can be incorporated in buildings and facilities to improve accessibility. Some projects relevant to subway systems have investigated the slip resistance of surfaces, contrast requirements for persons with low vision, the tactile readability of incised and raised letters, detectability of surfaces by cane and foot, and lighting and finish requirements for signs. These projects relied on data developed through subject testing or experience of actual blind and visually impaired users of public transit. The reports from each of those studies contain a series of recommendations and a bibliography. The recommendations for rail transit stations and other fixed-guideway transportation terminals contained in this brochure are drawn from the above reports and other related research. The edge-cuing provisions are intended for use where a sizable drop-off exists. Such drop-offs, if not detected, could result in a fall into the path of a transit vehicle. In Automated Guideway Transit systems (sometimes called "people movers") where platform screens are provided with doors that open only when a vehicle is available for boarding. Edge-cuing is unnecessary. The studies did not present evidence that tactile cues are needed at other locations such as stairs or escalators (which usually have a metal service-plate detectable by cane and foot). However, recommendations for lighting levels, signage,and slip-resistance are applicable in other settings. When applying the recommendations below, it is important to keep in mind that all transit facility users, including those with visual impairments, must be able to detect and react to directional and safety cues in sufficient time and distance to take appropriate action. This principle applies to features such as signage and edge-cuing in relation to the way the facility is used. LIGHTING Good general illumination should be provided. Incandescent ceiling-mounted downlights should not be used as the sole source of illumination on any accessible route or space. Relatively uniform, diffuse general illumination is critical for people with various disabilities as well as for the general public. Especially on platforms and accessible routes, lighting should be uniform and free of glare. Ceiling mounted downlights and similar directional lighting create alternating pools of light and shadow. Persons with glaucoma, cataracts and other conditions which cause light to be scattered and persons who wear corrective eyeglasses often experience extreme variations in reflected light as they pass beneath a succession of downlights. The phenomenon can be both disconcerting and dangerous. Substituting florescent panels for downlights creates more uniform illumination and can save money on electricity. Compared with incandescent lights, half as many fluorescent fixtures provide better, more uniform light at a fraction of the cost of installation, operation, and maintenance. There are many other satisfactory lighting systems which also provide adequate illumination and economy. Illumination levels in the areas where signage is located should be in the 100-300 lux range (10-30 footcandles): Based on tests of subjects, optimal success at reading a variety of signs and typefaces was achieved using alighting level of 300 lux (30 footcandles) at the sign panel itself. The ambient lighting level need not be as high when good lighting is provided at the sign. When the illumination level was reduced to 100 lux, the success rate decreased by 24%. When the illumination level was reduced to 100 lux, the success rate decreased by 24%. When the level was raised to 500 lux, the success rate decreased by 9%. In rapid rail transit systems where quick recognition of signs and directions is critical for everyone, slightly higher than usual lighting levels at signs may have a significant positive effect on ridership. Care must be taken, however, to ensure that glare is eliminated or reduced. EDGE CUING The edges of platforms should be identified with a material differing in resilience from the platform itself. Several research projects have tested the detectability by cane and foot of various materials. Tests showed that variations in resilience, sound and texture were detectable. However,despite stated requirements in some accessibility standards, textural changes in materials have been found to be the least detectable. In studies sponsored by the Access Board, differences in sound characteristics of surfaces tapped by a cane and differences in resilience could be detected most reliably. Since sound cues can be masked by transit vehicles, crowd noise, or echo, they are not suitable cues for use in transit facilities or for persons with hearing impairments. Difference in resilience between two adjacent materials appears to offer the highest detectability and the best solution for identifying transit platform edges. The cue results from the contrast between a hard and resilient surface. The cue should be consistent throughout the system. In some stations, the entire surface of the platform has been covered with a resilient material textured with raised circles while the platform edge is granite or concrete. Other systems have placed a resilient strip along the platform edge in contrast to the concrete or clay tile platform surface material. The edge-cuing material should extend the entire length of the platform edge and be at least 42 inches wide, starting at the platform edge. The difference between hard surfaces and various materials, ranging from relatively common vinyl or rubber flooring material, tennis court surfacing, and steel grating or plates, was detected by subjects within the distances of 30 inches to 48 inches. In both Access Board studies, and those conducted by other agencies, 90% of subjects stopped within 42 inches of the leading boundary between the different materials. The edge-cuing material should be firmly attached to the platform and maintained to prevent loose edges from becoming a hazard. Several common resilient surfaces can be detected by cane and foot in contrast to an adjoining material. However, installation and maintenance are critical to ensure that the material does not present a hazard to pedestrian traffic. All edges must be firmly attached to the platform substrate to prevent edges from becoming a tripping hazard. Installation of a continuous of nearly continuous strip may pose fewer problems than individual tiles. On the other hand, individual tiles may be easier to replace when damaged or dislodged. Careful consideration must be given to maintenance and installation before selecting a particular material. The edge-cuing material should visually contrast with the primary flooring by at least 70% as determined by the formula: Contrast = [(B1-B2)/b1} x 100 where B1 = light reflectance value (LRV) of brighter area B2 = light reflectance value (LRV) of darker area In general, the edge-cuing material should be the light areas. The research did not suggest that a particular color is important. Research sponsored by the access Board did not attempt to determine whether distinct identification of vehicle door position, as installed in some systems, has any effect. The same contrast ratio is also recommended for signs (see later section). The edge-cuing material, and floor surfaces of all accessible spaces and routes, should have a static coefficient of friction of 0.60. Obviously, the edge-cuing material and the platform itself should be slip-resistant. Persons with mobility impairments are more markedly affected than others by the surface characteristics of the flooring. Typically, persons without mobility impairments require coefficient of friction values from 0.2 to 0.3. Crutch users and amputees may require coefficients of friction ranging from 0.7 to 1.0, while wheelchair users require coefficients of friction of 0.5 to 0.7. Slip resistance should be measured with one of the testers, such as the NBS-Brungraber Tester, recommended in the "Slip Resistant Surfaces" report. In addition to slip resistance, the platform, accessible spaces and routes, and edge-cuing material should be stable (a surface that remains unchanged by contaminants, temperature, or applied force, so that when the contaminant or force is removed, the surface returns to its original condition) and firm (a surface that resists deformation by either indentations or particles moving on the surface) so that it does not pose a hazard or decrease the accessibility to persons with other disabilities. SIGNAGE The characters and background of signs should be eggshell (11-19 degree gloss). Eggshell is a standard designation of finish which minimizes reflectance yet permits cleaning of a sign surface. Matte finish soils easily, is difficult to clean, and is susceptible to vandalism. Directional, informational and emergency signage characters should be no smaller than 1/2 inch and visually readable at the minimum practical viewing distance. People generally adjust their viewing distance to read signs. Therefore, signs with small characters must be able to be approached closely. Subjects tested were able to read signs with 2-inch capitals from an average distance of 6 feet. Results indicate persons with low vision need to be ten times closer to read a sign than those with normal vision. Projecting the size/distance scale developed in research suggests 1-inch caps should be viewable from a maximum distance of 3 feet, 2-inch caps should be viewable from a maximum distance of 9 feet, etc. Thus, the 1/2 inch cap sign must be approachable to within 1.5 feet to be legible for persons with limited vision. Since most overhead signs are suspended somewhere between 7 and 9 feet, and the eye-level of a wheelchair user is about 4 feet, a wheelchair user with a visual impairment would need to be able to approach to about 5 feet of the vertical plane of the type of sign commonly used in terminals (3-inch caps). This suggests, if the sign needs to be read quickly or while the viewer is moving this distance may be too short and the sign characters should be larger. The spacing between letters should be "wide" by industry practice; generally, the space between letters should be 1/16 the height of capital letters. Wide spacing was found to be easier to read for persons with low vision and helped to reduce the halo-effect around letters in internally lighted signs. Space between words should be equal to the capital height for words with all capitals and 6/10 of capital height between capitals and lower case letters. Letters on signs intended to be read by touch should be raised, upper case, sans serif or simple serif type. Tests have shown that incised letters, permitted under some standards, cannot be reliably read by touch. For signs intended to be read only visually, no statistically significant differences were found between serif and sans serif type except for type faces with extreme flourishes and deviations in stroke width (e.g., Columbian Italic). For signs that must be read and understood quickly, especially for life safety, sans serif typefaces with optimal proportion and stroke width (e.g., Helvetica Medium and Helvetica Regular) are best. Characters should be light on a dark background and contrast with their background by at least 70%. Under the same lighting conditions, dark characters on a light background were significantly harder to read by test subjects. The contrast ratio is determined by the equation noted above for contrast of platform edge-cuing. Pictograms should be accompanied by the equivalent verbal description below. For a 6-inch sign (border dimension) a 1-inch capital height is suggested. large pictograms (6 inches) were more effective than smaller ones, suggesting a minimum size for directional and informational signage. ADDITIONAL CONSIDERATIONS Some of the recommendations from research sponsored by the Access Board are for changes to the regulatory requirements which will be considered by the Board during future rulemaking. Other recommendations are not easily quantifiable or may require further research to verify conclusions. For example, public address (PA) system announcements are a vital source of information, but can also be a cause of both confusion and irritation for all people, especially in large, open areas such as those in transportation terminals and airports. Such announcements are frequently unintelligible due to poor-quality sound systems, poor acoustics of the facility, or lack of training of persons making the announcements. Moreover, these factors are affected by noise such as arriving or departing trains. Rather than improving intelligibility, increasing volume usually increased distortion. Some transportation facilities have begun introducing automatic verbal directional information, such as "talking signs" to direct people to stand to the right on escalators or announce that a particular train is entering the station. Research has determined that, where such announcements are provided, the voice should be recorded or digitized human speech rather than synthesized speech. For such verbal information and for PA announcements, the placement of more speakers, at lower power, often is more effective than increased volume. Noise in transit facilities is not only unavoidable, it provides valuable cues. The sound of an arriving train or the door-closing annunciator are important for everybody. However, extraneous noise which can mask other sounds should be avoided whenever possible. For example, the rush of air through high-power air conditioners or blowers can significantly interfere with the sound of a cane tap and can mask PA announcements. Sound characteristics are also important in emergencies when various alarms must be heard and correctly recognized. Characteristics of visual alarms for persons with hearing impairments are the subject of another technical assistance document available from the Access Board. Additional research also suggests that certain auditory alarm characteristics are more readily recognized than others, especially by persons with some hearing impairment. Preliminary results indicate that variable tone or intermittent alarms, rather than steady bells or tones, are easier to detect in noisy conditions. This subject will be covered by future technical assistance publications. Designers and transit operators needing further information on the recommendations contained in this brochure and other design considerations to improve access to all people should contact the Access Board at the address below: U.S. Architectural and Transportation Barriers Compliance Board 1111 18th Street, NW, Suite 501 Washington, DC 20036 (202) 653-7848 (voice or TDD) REFERENCES "A Multidisciplinary Assessment of the State of the Art of Signage for Blind and Low Vision Persons", final report, Dr. Edward Steinfeld, University of new York, Buffalo; sponsored by U.S. ATBCB, 2985 "Detectable Tactile Surface Treatments", final report, Jon Sanford, Craig Zimmring, Georgia Institute of Technology; sponsored by U.S. ATBCB, 1985. "Information systems for Low Vision Persons," Peter Muller-Munk Associates; sponsored by U.S. ATBCB, 1986 "Slip resistant Surfaces", final report, Dr. B.T. Kulakowski, Pennsylvania Transportation Institute, Pennsylvania State University; sponsored by U.S. ATBCB, 1988. "Tactile Warnings to Promote Safety in the Vicinity of Transit Platform Edges," Dr. Alec Peck, Billie Louise Bentsen, Boston College; Sponsored by the U. S. Department of Transportation, 1987. .TCEL. .