Web Accessibility

Web Accessibility has been defined as " anyone using any kind of Web browsing technology must be able to visit any site and get a full and complete understanding of the information as well as have the full and complete ability to interact with the site - if that is necessary." (Chuck Letourneau, Starling Access Services). For a full definition, see Accessible Web Design - A Definition.

Types of Disabilities.

Cognitive, learning, or developmental disabilities:
These may include individuals with dyslexia, individuals for whom English is a Second Language, individuals who are poor spellers. Technical accommodations may include screen readers with speech synthesis. Web design solutions may include design of pages with consistent layouts and color schemes, and navigation buttons with clear meanings, used consistently. Captioned video clips would also benefit non-native English speakers.
 
Hearing disabilities:
The hearing impaired rely upon text and graphics for information. For deaf individuals whose native language is American Sign Language, and for whom English is a second language, there may be more reliance upon graphic information. In general, content is not lost when sound is turned off. However, if your web pages utilize audio clips, provide transcripts for the hearing impaired.
 
Motor disabilities:
Individuals with motor disabilities may vary from those with repetitive stress injuries or arthritis to those with quadriplegia. Some may have difficulty using a mouse or holding down multiple keys simultaneously, while others may need special adaptive software and equipment, including alternative input devices. From the web design point of view, make sure that your links and hot images are not too small, and that people do not have to jump around. Also, if you use forms (requiring a mouse), be sure to provide alternate means for submitting the information.
 
Visual disabilities:
Web users with visual impairments may be totally blind, partially blind, or have low vision or color blindness. Blind users may use screen readers with voice synthesizers or Braille output. Tables and columns will be a problem for this group. Blind users cannot see your images or use your mouse-driven forms. Those with partial or low vision or color blindness may have difficulty with your use of wallpaper and choice of colors.
 
"Economic" disabilities:
Not everyone can afford to buy the latest computer and have fast connections to the web. The disabled, who are often unemployed or underemployed, and others with limited means may be using a slower computer, an older browser or text-based browser such as Lynx, and a slower modem. Can this population access your web page, or have you designed pages that only work with the latest browser, load slowly, and require half a dozen plug-ins?

Barriers to the Web for the Disabled.

The following limit or restrict access for Web users who are impaired and/or are using Lynx (a text-based browser), an older browser such as Netscape 2.0, a slower modem, etc.:

  1. Graphic images.
  2. Image maps (An image in an HTML document with "hot spots" which act as anchors or links to other information. You need to click on a certain area in order to follow the link).
  3. Audio and non-captioned video.
  4. Forms and databases.
  5. Frames (A way to display more than one page of HTML on the screen at a time).
  6. Tables (an HTML syntax consisting of rows and columns used to lay out information).
  7. Inaccessible file formats such as Portable Document Format (PDF). PDF (e.g., Adobe Acrobat) is a format that provides a way to capture a file, whether it be a text document or a computer-aided design, so that when it is viewed on different platforms by different people, it maintains the same look and feel.

Tips for Designing Accessible Web Pages.

Some of the accessibility factors that Web designers should consider include:

  1. End all headers, list items, and sentences with a period or other appropriate punctuation. This will aid the visually handicapped user with a screen reader.
  2. Use vertical lists of links when possible. Avoid multiple links on the same line.
  3. Avoid the use of columns (tables). Columns of text are inaccessible with a screen reader, which reads text left to right, straight across the page. Also, some browsers do not support tables. Try using headings, paragraphs, lists, and definition elements instead.
  4. Put a text menu near an image map, or create a link to a text-only page (An alternate form of a Web page that only presents text. It is commonly used with complicated graphical pages to decrease download time and increase the ease of interpretation by people unable to view graphics).
  5. Avoid frames. If you must use frames, offer a no-frames, text-only version.
  6. Provide alternate (aural and textual) descriptions of images.
  7. Provide e-mail links and contact information as an alternative to forms-based pages or databases. Forms and databases may not be accessible to the visually handicapped or those with motor skills problems. If you do use forms or a database, test them with a text browser such as Lynx.
  8. Avoid the use of tables, especially embedded tables (i.e., tables within tables). Again, if you must use tables, offer a text-only version.
  9. Choose color for backgrounds, text, and links carefully. Textured backgrounds are difficult to see. Keep backgrounds simple; many background colors and images obscure text. Use the 216-color safe palette. Low vision readers need high contrast. Remember that the user can override your fonts and colors.
  10. Avoid the use of "Click Here." This is not helpful to the visually impaired.
  11. Do not use graphics by themselves as links. Graphics don't talk.
  12. Provide Alt text tags for images. Alt text tags are descriptive text information accompanying an image or graphic embedded in HTML. When a user chooses not to view graphics, or uses a text-based browser, this is displayed instead of the image that it associated with it. For longer descriptions, use D-links: a text anchor placed next to or below a graphic that links to a detailed description of the associated graphic.
  13. If you publish documents in PDF you should inform users in plain text that PDF is being used and you should indicate that an accessible plug-in exists for screen readers, and link to it.
  14. Use logical styles such as <STRONG> or <EM>.
  15. Design large buttons for those with mobility impairments, and include text links. For an example of large buttons, see Accessible Web Page Design: Table of Contents, below.
  16. Maintain a simple, consistent page layout, with elements such as a logo or navigational menu in the same place on each page.
  17. Use drop-down boxes, which can be read by screen readers, instead of radio buttons or check boxes, which cannot.
  18. Use Cascading Style sheets rather than tables. Style Sheets describe how documents are presented on screens, in print, or perhaps how the words are pronounced. A designer can redefine how browsers interpret and display basic HTML.
  19. Test your Web page with a Web page validator, such as Bobby (see below).

Useful Links: How-To.

Accessible Design for Users With Disabilities.
Information on visual, motor, auditory, and cognitive disabilities and the barriers encountered on the Web by people with these disabilities. Includes suggestions for accessible Web page design. http://www.useit.com/alertbox/9610.html
 
All Things Web: Compatibility and Accessibility.
Articles on Web accessibility design, offering tips on making Web pages more accessible. Includes Some Readers...Aren't (not all Web page visitors are readers), Could Helen Keller Read Your Page? (technical tips on Web page accessibility), The Art of ALT (effective use of ALT text) and Accommodating Imperfection (designing for accessibility for those with visual and motion impairments). http://www.pantos.org/atw/access.html
 
Better Access to the Web for Blind and Partially Sighted People.
Information on how the visually impaired access the Web, recommendations for making Web pages more accessible, and links to additional resources. http://www.braillenet.org/accessibilite/livreblanc/english/index.html
 
Creating Widely Accessible Web Pages.
"This chapter will acquaint you with the key considerations, existing solutions, and perspectives of development in the area of web accessibility. You'll learn how your web pages can be made more disabilities-friendly with today's technology and with minimal or no additional investment." http://www.webreference.com/dlab/books/html-pre/42-0.html
 
Designing More Usable Web Sites.
Links to the Web Accessibility Initiative, accessible Web site guidelines, Web access tools, Java accessibility, Web browsers with voice and accessibility features, browser design/screen reader sites, and more http://tracecenter.org/world/web/
 
National Center for Accessible Media Web Access Project.
"The Web Access Project researches, develops and tests methods of integrating access technologies (such as captioning and audio description) and new Web tools into a World Wide Web site, making it fully accessible to blind or deaf Internet users." http://ncam.wgbh.org/webaccess/
 
Six Principles of Accessible Web Design.
Introduction to the Web authoring guidelines of the Web Accessibility Initiative. http://www.hwg.org/resources/accessibility/sixprinciples.html
 
Untangling the Web: An Introduction to Web Design.
Article for visually impaired individuals in May, 2004 AccessWorld onthe basics of creating and publishing documents on the World Wide Web. http://www.afb.org/afbpress/pub.asp?DocID=aw050307
 
Web Accessibility Initiative.
"The Web Accessibility Initiative (WAI) works with organizations around the world to develop strategies, guidelines, and resources to help make the Web accessible to people with disabilities " http://www.w3.org/WAI/ Their Web Content Accessibility Guidelines 2.0 (explaining how to make Web content accessible to people with disabilities) were issued on 11 Dec 2008: http://www.w3.org/TR/2008/REC-WCAG20-20081211/
 
Web Authoring Strategies for Voice Browsers.
Position paper outlining some of the primary techniques of Universally Accessible Design as they relate to voice browsers, and offering ideas as to how authors can implement these considerations. http://www.hwg.org/opcenter/w3c/voicebrowsers.html

Useful Links: Resources and Products.

 
Access at Adobe.
PDF documents are not accessible to the blind or visually impaired. This Web site is a starting point for learning more about converting Adobe Acrobat (PDF) documents to HTML or ASCII. http://access.adobe.com/
 
Accessible Web Design Class.
"The World Wide Web was created as one of the most inclusive media; anyone, regardless of computer type, operating system, or browser version, could access information on the Web. But then something went wrong. Today's web is full of thoughtlessly designed sites which can't be accessed by a diversity of web browsers. Users with special needs, such as those with physical disabilities, are often shut out from essential e-commerce facilities, distance learning programs, and web-based news systems. Why did this happen, and how can we fix the problems without tearing down attractive, dynamic web sites and replacing them with text-only pages."
http://www.hwg.org/services/classes/accessibilitydesign.html
 
AccessWorld: Technology and People with Visual Impairments.
"A free, web-only magazine, AccessWorld is a bi-monthly publication dedicated to anyone who uses or wants to use assistive technology, provides technology training, has students or clients who use technology, needs to make purchasing decisions, or wants to keep abreast of technological trends and events.  AccessWorld is the only publication that seeks to provide people who are blind or visually impaired, the blindness field, the technology community, and anyone else interested in technology with news and objective, reader-friendly product evaluations that foster informed purchasing decisions and intelligent application of technologies. " http://www.afb.org/aw/main.asp
 
Alliance for Technology Access (ATA).
"The Alliance for Technology Access (ATA) seeks to redefine human potential by making technology a regular part of the lives of people with disabilities. The ATA is accomplishing this by raising public awareness and implementing programs and initiatives that provide access to conventional, assistive and information technologies, related services and resources." Provides information on adaptive devices, software, and Web page design techniques that enhance access to the Web for individuals who encounter vision, hearing, learning/cognitive, physical, or economic barriers at Web sites. http://www.ATAccess.org/
Apple Accessibility.
Describes Macintosh assistive technologies for people with disabilities. http://www.apple.com/accessibility/
 
AXSLIB-L.
A listserv for librarians to learn how to accommodate patrons with disabilities. To subscribe to the AXSLIB-L list, send e-mail to listserv@maelstrom.stjohns.edu saying sub axslib-l (and include your first and last names).
 
 
EASI: Equal Access to Software and Information.
"People with disabilities must have the same access to information and resources as everyone else. EASI's mission is to promote this access through 1, on-site and on-line workshops; 2, publications and videos; 3, e-mail discussion lists; 4, web site; 5, electronic journal; and 6, through participation in a wide variety of regional and national conferences." EASI also offers courses on barrier-free web design. http://easi.cc/
 
IBM Accessibility Center.
"IBM has developed a number of assistive devices and software tools that make the computer more accessible and friendly to people who have vision, hearing, speech, mobility, and attention/memory disabilities. These products include everything from interactive speech and cognitive therapy tools, to screen reader software and keyboard access utilities, to screen enlargement programs." http://www-306.ibm.com/able/
 
Java Accessibility and Usability Work.
Links to several sites describing Java accessibility developments, projects, and example pages. http://tracecenter.org/world/java/java.htm
 
Microsoft Accessibility.
Microsoft's Accessibility page provides an overview of accessibility, definitions of disabilities and accessibility, types of accessibility aids, statistics on disabilities, and information on accessibility features of Microsoft products as well as other accessibility products. http://www.microsoft.com/enable/
 
Usability.gov.
U.S. Department of Health and Human Services web page of resources for "designing usable, useful, and accessible web sites and user interfaces." http://www.usability.gov/index.html
 
Viewable with any Browser.
Campaign to promote a non-browser-specific web accessible to everyone. http://www.anybrowser.org/campaign/abdesign.shtml
 
WebAIM (Web Accessibility in Mind)
"Web Accessibility In Mind (WebAIM) is administered through a grant provided by the Learning Anywhere Anytime Program Fund for the Improvement of Postsecondary Education. Our goal is to improve accessibility to online learning opportunities for all people; in particular to improve accessibility for individuals with disabilities who currently may have a difficult time getting access to postsecondary online learning opportunities." Offers training, how-to resources, articles, and information on web accessibility. http://www.webaim.org/
 

Print Resources.

Alliance for Technology Access. Computer and Web Resources for People with Disabilities: A Guide to Exploring Today's Assistive Technology. 3rd ed. Alameda, CA: Hunter House, 2000.

Clark, Joe. Building Accessible Websites. Indianapolis: New Riders Press, 2003.

Mates, Barbara T. Adaptive Technology for the Internet: Making Electronic Resources Accessible to All. Chicago: American Library Association, 2000. Also available full-text on the Web: http://www.ala.org/editions/openstacks/insidethecovers/mates/mates_toc.html
 
McNulty, Tom, ed. Accessible Libraries on Campus: A Practice Guide for the Creation of Disability-Friendly Libraries. Chicago: Association of College and Research Libraries, 1999.
 
Paciello, Mike G. Web Accessibility for People with Disabilities. Lawrence, KS: CMP Books, 2000.

Thatcher, Jim, et al. Constructing Accessible Web Sites. Birmingham, U.K.: Glasshaus, 2002.

Waters, Crystal. Universal Web Design: A Comprehensive Guide to Creating Accessible Web Sites. Indianapolis: New Riders, 1997.
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