Southwest Educational Development Laboratory
Volume 2, Number 1, 1997
The Internet: A Word from the Director
Accessible Information on the World Wide Web
→ General Guidelines For Improving Accessibility of World Wide Web Pages
Accessibility Design Considerations and Examples
NIDRR Project Results Used by Special Olympics International to Evaluate Impact of Sports Program
Good Web page design responds to the needs of viewers with disabilities. A commitment to making a site accessible requires some additional planning and testing, in addition to specific changes to documents or files. Most changes or additions to increase accessibility are small, and can be easily implemented. Making a Web page accessible should be routinely incorporated as a normal part of design and development rather than viewed as an afterthought.
The purpose and content of your site will help determine its design. You may want your site to heighten awareness of your NIDRR project or institution, and explain your goals, activities, and how to contact the staff. Its purpose may be to demonstrate or share information gathered from your research, or to provide free access to products developed through your project's work. Full-text documents can be made available, as well as product catalogs and ordering information. You may decide that your Web site will be interactive and invite input from users.Design your site to be inviting and to take advantage of the capabilities of the WWW. Your site must help potential users locate relevant information they may need, and encourage them to return because of the content they find. When you design your site, make allowances for it to grow. You must keep it updated, so changes should be planned for and not viewed as disruptive.A clear, well-defined purpose will serve to guide site development. As ideas for content or specific pages are proposed, checking to ensure they further or fit in with the stated purpose will make the site cohesive and focused.
The audience of your site will also be determined in part by its design and content. Asking for input from potential users in the planning stages will assist in ensuring your site achieves its purpose. If you have information to offer people with disabilities, your site must be accessible for those members of your audience. You do not want to prevent potential users from navigating your site, or to alienate them by ignoring their needs. A site with numerous graphic images may be confusing for people who are using a screen reader, as well as others who use text-based browsers or who (due to the download time involved) turn graphics loading off. Numerous audio and video clips may not be accessible to users who are deaf or hard of hearing, or to people lacking software or hardware to access or play sounds and movies. These features may be attractive or useful additions for some users, but alternatives such as text files and transcripts should also be made available in order to welcome all potential viewers and users of the information at your site.It may be helpful to add features to help identify your audience, those who actually visit your site. Software is available to count the number and origin of users and the pages most often viewed. A feedback form, survey, or guestbook will also help you learn more about your audience.
As technology continues to advance, many access problems may be solved, and new ones may appear. One of the advantages of the Web is that users with a variety of hardware are able to access information that is provided by different platforms (such as UNIX, DOS, or Macintosh). The platform used for the server has certain capabilities that define how and how much information will be 'uploaded' to the Internet. Machines with smaller capacity or slower capabilities may affect the time it takes a user to access or download information. Server capability also determines how many visitors can access the site at one time. It would not be prudent to design a site with extensive use of graphics, audio, and video if the capacity of the server will impede users' access to information.
Differences in users' equipment and software will also affect how they receive information. Although developers have no control over how users will access their site, you can make an effort to accommodate those with different needs. Users with disabilities may avoid your site if the initial pages are too difficult to navigate. People with older, slower equipment will become frustrated waiting for long files or large graphics to load. This is the origin of the term 'World Wide Wait.'The way a user accesses the Internet affects his or her ability to view documents. People who use commercial services such as America Online, Compuserve, and Prodigy will have different capabilities from those who reach the Internet from universities, business or technical sites, or others with independent Internet Service Providers (ISPs).
Browser software determines how Web pages appear to each user. The pages at your site will present some variations depending on the browser used by the viewer. A text-based browser such as Lynx will show phrases such as [IMAGE], [INLINE], or [LINK] when graphics are not able to load. This lets the user know something is there, but it does not identify the item in a way that informs the user. Modifications are needed to identify graphics. Different versions of browsers like Netscape Navigator, Internet Explorer, and Mosaic also have different capabilities. It is helpful to review your pages with several different browsers to ensure that all users can view what you intended to produce.
Some Web sites inform visitors "This site is best viewed with "XXX Browser, Version 1.x." Others even include information about fonts, colors, and resolution in order to view the site at its best. Instead of informing users how they should change their settings to meet a site's development standards, a more universal design approach is to make the site compatible with a variety of browsers. The 'Best Viewed With Any Browser' campaign (developed by Cari D. Burstein, http://www.anybrowser.org/campaign/) supports using standard HTML notation that is properly interpreted by all browsers. Viewers with disabilities will also benefit from this approach.
Special software has been developed for users with disabilities, including browsers. For example, The Productivity Works, Inc. has developed pwWebSpeak, a non-visual browser with a built-in speech processor and enlarging format that interprets from the HTML code rather than what appears on the screen (Lazarro, 1996; Sreenivasan, 1996). Microsoft Internet Explorer Version 3.0 uses the Active Accessibility program, also developed by Microsoft, to facilitate use of screen reader software, synthesizers, Braille displays and large print programs (Lazzaro, 1996). Netscape is also working to increase the capabilities of its Navigator browser to meet the needs of users with disabilities (Sreenivasan, 1996). The goal of the Access Project is to identify some of the major barriers people with disabilities encounter on the Web, and where feasible, design and implement solutions.
An organized layout is critical for a well-planned site. The layout should serve to orient the user to where information is likely to be found, and to facilitate moving through the site. Keeping similar features (including navigation aids such as Back, Forward, Previous, Next, Home, etc.) in the same place on all pages helps all users, and especially those with disabilities. A branching tree structure allows the site to grow as things are added following a logical format rather than random expansion. The layout should not be too crowded, or include pages with little content or nothing but links. Pages with only graphics should also be avoided.
The proper size of a Web page document is difficult to determine. Downloading time is one way to judge the size of a document, although this will also vary depending on the capabilities of the server and user. A download time of more than 30 seconds may cause some users to stop a download. More than ten screens of information (again, this will vary!) can also turn many users off. If it is necessary to save many separate parts and then integrate them to be able to print a complete product, the individual parts may be considered "too short." On the other hand, one large document may be too slow in loading, or may cause readers to scroll through, looking for what is important to them. One option is to provide a link to a file containing a complete plain-text (ASCII) version of the document. This file would be more accessible for screen readers, and an end-user could easily download it for printing.
Colors should contrast well with the lettering to maintain readability. Select colors that will make your pages easy to read by people with color blindness. One good test is to see if your pages are readable in black and white. In most cases, it is advisable to avoid background (wallpaper) patterns as the images and/or colors can impede accessibility for people with limited vision or who use screen readers. Text should be clear and uniform for easiest reading. Using a large font is not necessary, because most viewers will adjust the fonts on their browsers and a large font might then be too large to provide continuity if only a few words are visible at a time.
The ability to get input from users is an important aspect of the World Wide Web. The purpose and layout of the site will help determine if input from users is encouraged or discouraged. One way to ask for input is to provide links for electronic mail ("mailto"). Using an animated graphic for that purpose may not allow users who are blind to find and use the e-mail link unless a standard mailto link is also available.
The use of forms is another way Web sites invite input from users. Some text-based browsers cannot use forms, although more recent versions of Lynx have resolved that issue. A separate text-based form that can be completed and sent by electronic mail, or printed and faxed or sent by surface mail, gives an opportunity for users without forms capability to respond.Providing no avenue for feedback by users indicates that the opinions of the viewers are not valued. It is important to facilitate feedback from users with disabilities, including feedback on the accessibility your site.
One of the powerful tools of the Web is the ability to link to other documents and sites through 'hyperlinks' that allow users to move rapidly to sites all around the globe. It is not necessary to reproduce information at your site that is available elsewhere -- just provide a link. In thinking of accessibility, though, it is important to consider the accessibility of those sites to which you may want to link. In some cases, you might decide not to link to a site where people with disabilities may have difficulty navigating. It would also be helpful to alert users that some linked sites may not be accessible.Too many links throughout your documents may encourage visitors to 'surf'" and not return to your pages.
Within your site, be sure to give users a way to return to the place they were before leaving by providing a return link. Many lists of links are not recommended. Content is an important reason for hosting a site, and the links should enhance the content you present.One problem with links relates to the evolving nature of the Internet and the Web. As newer hardware is installed or sites are reorganized, the Web address (Uniform Resource Locator, or URL) of a document or an entire site may change. Without follow-up, the links you provide in your site may not stay active.
A site should continually evolve; it should not be a static product. In order for visitors to want to return to the site, they must be made aware of the new or updated items they can find. If information is loaded onto the server and then never modified or updated, in a short time, it will not attract new or repeat visitors. To be useful, the site must have interesting, up-to-date information. It is important that the date of the most recent revision is available on each document. As technology advances, you should plan to make improvements at your site to enhance accessibility for users with disabilities.
It is easy to test your WWW pages using a variety of text browsers and platforms (PC, MAC, UNIX). Even if you use a graphical browser, you can see how a page will look to others by de-selecting image loading under 'Preferences,' and viewing your pages again. There are a number of sites on the Web that convert a document to show how it will appear using the text-based Lynx browser. Other validation sites available can assist you in assessing the "correctness" of HTML code and its accessibility.BOBBY is an example of new technology that is available to you.
Bobby is a graphical web-based program designed to help make Web pages accessible by the largest number of people. A free service, it was developed by the Center for Applied Special Technology (CAST) Universal Design Lab staff and Josh Krieger. Founded in 1984, CAST is a not-for-profit organization whose mission is to expand opportunities for individuals with disabilities through innovative computer technology.Bobby performs a series of tests to determine the ways in which a Web page is inaccessible to people with blindness, deafness or physical disabilities. It identifies problems and gives Warnings and Suggestions to correct them. In addition, Bobby will help find design problems which prevent a Web page from being displayed correctly on different Web browsers (America On-Line, Netscape Navigator, Mosaic, Microsoft Explorer, Lynx) without having to individually test the page with each browser.
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Return to Accessible Information on the World Wide Web article
Return to World Wide Web article
LaPlante, M. (1992, December). How many Americans have a disability? Disability Statistics Abstract No. 5. San Francisco: Disability Statistics Program, University of California. [Online]. Available: http://dsc.ucsf.edu/UCSF/pub.taf?_UserReference=E2E368275984CA0CBCB8C605&_function=search&recid=65&grow=1
Lazarro, J.J. (1996, December). Browse the Web with your eyes closed. Information Technology and Disabilities(ITD-JNL) 3(4). [Online] Available: from the listserv ITD-JNL@sjuvm.stjohns.edu (12-21-96).
Return to General Guidelines article
NCDDR. (1997). Survey of consumers with disabilities: Report of field test results. Austin, TX: Southwest Educational Development Laboratory.
New Networks Institute. (1996). Executive summary: Online and Internet statistics reality check, '96. [Online]. Available: http://www.newnetworks.com/statsexecsum.htm No longer available on the World Wide Web.
Smith, G. & Kimball, T. (1997). Are there one million disabled Internet users? Personal communication by electronic mail, February 26, 1997.
Return to World Wide Web article
Sreenivasan, S. (1996, December). New software improves Web access for the blind. New York Times News Service, December 2, 1996.
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Trace Center. (1995, December). The principles of universal design. Version 1.1. Madison, WI: University of Wisconsin. [Online]. Available: http://www.tracecenter.org
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