November 15, 2004 Program Summary

Designing Web Sites for Accessibility
by Adele Sommers

Reaching for inaccessible computerHave you ever wondered how you would use a computer or surf the Internet without the use of your eyes, hands, or other senses? In this enlightening presentation, speaker Mary Meyer explained several of the limitations people can overcome through a combination of specialized technology and complementary Web design.

Adaptive tools make computers in general, and Web sites in particular, more usable by people who can't interact easily with standard keyboards, mice, or screen resolutions, Mary explained. An impressive array of adaptive tools already come standard with newer operating systems. Third party vendors offer a variety of others.

According to Mary, the beneficiaries of these tools are people with limitations ranging from mild age-related sight impairments to profound injuries that restrict arm and hand movements. Anyone can use the built-in assistive technology found in Windows, for example. Many people regularly magnify the size of text, hear text read aloud, and take wrist-friendly keyboard shortcuts, among other things.

But the story doesn't end with the latest adaptive technology, Mary cautioned. We'd have no reason to be concerned about good Web site design if the technology could do everything by itself. The technology works far better when the site design anticipates how it might be used. To learn how these elements work together, see the highlights of Mary's presentation, below.

What is Section 508 of the Rehabilitation Act of 1998?

Mary explained that Section 508, an often-quoted government Web site accessibility standard, is a 2001 amendment to the Rehabilitation Act of 1998. This amendment reinforces the engineering design requirements and features that must be present in telecom and information systems developed, procured, leased, maintained, or used by the government to:

  • ensure that disabled government employees can access the government's internal electronic communication and information systems, and
  • verify that disabled people in the general public can use the government's public access systems.

Many non-government organizations also have started using Section 508 as a design guideline. “It only makes good business sense,” Mary said, “to make sure that all of your potential customers, including those who are disabled, can learn about and purchase your products and services.”

What kinds of disabilities affect Web use?

Mary cited an eye-opening study commissioned by Microsoft Corporation and conducted by Forrester Research, Inc. in 2004. (The findings reside in Microsoft's section on accessibility.) This study revealed that among adult computer users in the United States:

  • 27% have a vision difficulty that may entail low vision, color blindness, or blindness. The most common form of color blindness is red-green, Mary said, which affects mostly males. A standard design guideline that helps all users is providing alternative cues, in case colors don't display well. Alternative cues include alt tags for images, bolding, and underlining for links.
  • 26% have a dexterity difficulty involving pain, discomfort, or complete loss of feeling in their fingers, hands, wrists, or arms that makes it difficult to use a standard keyboard or mouse. Common illnesses and accidents such as carpal tunnel, arthritis, stroke, cerebral palsy, Parkinson's disease, multiple sclerosis, loss of limbs or digits, spinal cord injuries, and repetitive stress injury, among others, can cause dexterity problems.

Mary highlighted other physical impairments that can affect computer and Web use (this information also derives from Microsoft's section on accessibility):

  • Language and speech difficulties, which can include aphasia (loss or impairment of the power to use or comprehend words) and various other cognitive, problem-solving, and memory impairments.
  • Learning difficulties, including dyslexia, attention deficit disorder, and retardation. These difficulties can be mitigated by presenting information in a way that optimizes the form, sensory delivery modes, and pacing for applicable learners.
  • The effects of aging, which increasingly limit computer use and Web interaction through decreasing vision, hearing, and/or physical dexterity.

How does assistive technology support each disability?

Assistive technology products, Mary emphasized, extend accessibility to individuals who have physical or cognitive difficulties, impairments, and disabilities. To be usable, however, they must be compatible with the operating system and programs on a particular computer.

Type of Challenge
Assistive Technology Available
  • Alternative Cascading Style Sheets (CSS) - especially useful for changing default color combinations that a colorblind user cannot see clearly, and for setting text display preferences
  • Screen enlargers
  • Screen readers
  • Voice recognition
  • Speech synthesizers
  • Refreshable Braille displays
  • Braille embossers
  • Talking word processors
  • Large-print word processors
  • Speech recognition systems (speech-to-text systems)
  • On-screen keyboard programs
  • Keyboard filters, such as word prediction utilities and add-on spelling checkers
  • Touch screens
  • Alternative input devices
  • One-handed keyboards and other keyboard variations
  • Sound options, such as volume controls, are typically built into operating systems.
  • Otherwise, information can be presented visually, such as through a text version or closed captioning of all verbal elements. (This need also exists if target users don't have computer speakers.)
Language and speech
  • Keyboard filters
  • Speech recognition systems
  • Screen review utilities, which convert on-screen words into synthesized speech as well as emphasized visual representations
  • Touch screens
  • Speech synthesizers (text-to-speech systems)
  • Word prediction programs
  • Reading comprehension programs
  • Reading tools
  • Speech synthesizers
  • Speech recognition systems

Adjustable features in operating systems such as Windows XP enable users to do the following, and more:

  • Increase icons and text size
  • Open a floating window that functions like a magnifying glass
  • Use speech recognition to minimize typing
  • Use a visual warning in lieu of system sounds
  • Use of a screen reader to read on-screen text
  • Adjust the size and look of the cursor
  • Use Mouse Keys to replace navigation with a mouse, or select from different mouse shapes and styles
  • Adjust screen resolution and/or contrast


How do you design a Web site to work with assistive technology?

The purpose of designing a Web site for accessibility is to work in tandem with, but not to replace, assistive technology, Mary reemphasized. She recommends considering the accessibility guidelines below as you are designing.

Things to do:

  • Use descriptions wherever possible: For graphics or animations, use the alt attribute to describe the function of each. For text links, scrolling text, and Flash movies, all of which cannot use alt tags, use the title* attribute to create descriptors. For graphs and charts, either summarize or use the longdesc* attribute.

    *The title and longdesc attributes are available as special Web design plug-ins. For example, Macromedia provides these as downloads for its Dreamweaver Web design software.
  • Image maps: Use the client-side map and text for hotspots.
  • Multimedia: Provide captioning and transcripts of audio, and descriptions of video.
  • Hypertext links: Use text that makes sense when read out of context.
  • Page organization: Use headings, lists, and consistent structure. Use CSS for layout and style where possible.
  • Scripts, applets, and plug-ins: Provide alternative content in case active features are inaccessible or unsupported.
  • Frames: Use the noframes attribute and meaningful titles. Consider CSS rather than frames.
  • Tables: Make line-by-line reading sensible, and summarize.
  • Navigation: Use “skip to main content” and other shortcuts to avoid causing screen readers to repeatedly verbalize the navigation headings on each page.
  • Testing: To determine whether a Web site is at least satisfactory for disabled users, even if not completely accessible, you can do an accessibility check with assistive technology software such as Watchfire.com's Bobby (http://bobby.watchfire.com/bobby/html/en/index.jsp).

Things to avoid:

  • Color dissonance: Avoid using color combinations with poor contrast, and avoid hard-coding color choices directly in the body of pages. Use a CSS instead to specify color attributes so that users can override these attributes, if desired, using their own alternative CSS.
  • Over-specifying text color, size, and font: Avoid hard-coding text display information into the body of pages. Use a CSS instead to specify text display attributes so that users can override them. Use relative text sizes and font families whenever possible.
  • Unclear text emphasis: Avoid underlining any words that aren't links. Minimize the use of cursive or italicized text, as it is difficult to read. Do not make color the only method of emphasizing important information. Always use a second form of emphasis to be sure it will not be missed.

Does usability differ from accessibility?

Many people would say no, but Mary's clarification helped put the concepts in perspective. Sites considered highly usable by people without impairments may not be very usable by people with them. Conversely, a site optimized for accessibility should be usable by everyone, with or without impairments. This idea is similar to the benefits associated with “curb cuts” in sidewalks. Such navigation aids make curbs easier to negotiate for all types of people, not just those with disabilities.

In summary, designing Web sites for accessibility involves factors that go beyond creating usable sites for non-impaired users. Accessibility ensures that assistive technology (such as a screen reader) can convey a clear picture of what is on a site and how to use it. These additional assistive technology design factors include:

  • Using alt, title, and longdesc attributes where applicable to describe graphics, animations, links, graphs, charts, and other non-text elements on the screen.
  • Providing captioning and transcripts of audio, and descriptions of video.
  • Using text for hypertext links that makes sense when read out of context.
  • Using “skip to main content” and other shortcuts to avoid causing screen readers to repeatedly verbalize the navigation headings on each page.
  • Using CSS for layout and style where possible.
  • Alliance for Technology Access, whose mission is to connect children and adults with disabilities to technology tools. See http://www.ataccess.org.
  • Web Accessibility Initiative (WAI) through the World Wide Web Consortium (W3C): See http://www.w3.org/WAI/.
  • The STC AccessAbility Special Interest Group (SIG) Web site: See http://www.stcsig.org/sn/index.shtml. This site is loaded with resources and information about disabilities, assistive technology, and more.
  • MERLOT-CATS site with Web accessibility information: See http://cats.merlot.org/Home.po and click the ADA Accessibility link on the right side of the page. MERLOT (Multimedia Educational Resource for Learning and Online Teaching), offered through the Community of Academic Technology Staff (CATS), is a community of people involved in education.
Designing Web Sites for Accessibility
Date: Monday evening, November 15, 2004

“Designing Web Sites for Accessibility” answered important questions about making Web sites user-friendly to people with various types of impairments or limitations. Sometimes the need arises unexpectedly because of workplace injuries, such as repetitive stress syndrome, which can turn the tables on our expectations of ourselves, our colleagues, or our employees.

To put the need in perspective by helping us walk in “other people's moccasins,” the presentation covered the following topics:

  • What is a “disability”? Why is accessibility important?
  • How do blind and low-vision users work with Web sites?
  • How do people with other types of disabilities work with Web sites?
  • What's the relationship between accessibility and usability?
  • What is Section 508 of the Federal Rehabilitation Act?
  • How do you design and test a Web site for people with various limitations?
  • What are good and bad examples of accessible Web sites?
  • What helpful software is available (such as speech-to-text products)?

Mary Meyer, M.B.A., M.A.T., is a PC trainer with InDyne Corporation at Vandenberg AFB, a part-time instructor at Allan Hancock College, and a member of our SLO STC board of directors. Her multi-faceted background encompasses technical communication, including Web design; several years in the training field; education of adults and children; emergency preparedness planning and management; bookkeeping; project administration, and more. Mary's Web site is http://Site-scribe.com.


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