Accessible Web Design
Most people today can hardly conceive of life without the Internet. It provides access to information, news, email, shopping, and entertainment. At the click of a mouse, the world can be "at your fingertips"-that is, if you can use a mouse . . . and if you can see the screen . . . and if you can hear the audio-in other words, if you don't have a disability of any kind.
The most universal format for perceivability is text, because it can be transformed into light for the eyes (on a computer screen), sound for the ears (through a screen reader), and Braille for the hands (through a Braille display).
The following resource table below, originally developed by Paul Bohman of , will help you in your future endeavors to try to implement principles of accessibility in your work. For a more updated and informative list, go to from the Trace Center at the University of Wisconsin-Madison.
Common Web Accessibility Challenges and Solutions
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Challenges
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Solutions
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Images, photos, graphics are unusable.
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Provide text descriptions, in "alt" tags and, if necessary, longer explanations (either on the same page or with a link to another page).
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Users often listen to the Web pages using a screen reader.
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Allow for users to skip over navigational menus, long lists of items, ASCII art, and other things that might be difficult or tedious to listen to.
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Users often jump from link to link using the TAB key.
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Make sure that links make sense out of context ("click here" is problematic).
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Users generally do not use a mouse.
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Don't write scripts that require mouse usage. Supply keyboard alternatives.
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Not all screen readers support image maps.
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Supply redundant text links for hot spots in image maps. |
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It may be difficult for users to tell where they are when listening to table cell contents
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Provide column and row headers (<th>). Make sure that tables--especially those with merged cells--make sense when read row by row from left to right. |
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Complex tables and graphs that are usually interpreted visually are unusable.
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Provide summaries and/or text descriptions.
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Frames cannot be "seen" all at once. They must be visited separately, which can lead to disorientation.
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Don't use frames unless you have to. If you use them, provide frame titles that communicate their purpose (e.g. "navigational frame", "main content").
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| Colors are unusable. |
Do not rely on color alone to convey meaning.
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Users expect links to take them somewhere.
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Don't write scripts in links that don't have true destinations associated with them (e.g. href="javascript: function(this)").
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| Challenges | Solutions |
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Reds and greens are often indistinguishable.
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Avoid juxtaposing these colors.
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Other colors may be indistinguishable.
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Make sure that there is sufficient contrast, and that the pages would be readable on a black and white monitor. To simulate this, print your Web page to a black and white printer.
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| Challenges | Solutions |
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Users often use screen enlargers.
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To reduce that amount of horizontal scrolling, use relative rather than absolute units (e.g. use percentages for table widths instead of pixels).
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Text in graphics does not enlarge without special software, and looks pixelated when enlarged.
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Limit or eliminate text within graphics.
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| Challenges | Solutions |
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Audio is unusable.
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Provide transcripts for audio clips.
Provide synchronous captioning for video clips. |
| Challenges | Solutions |
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Users may not be able to use the mouse.
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Make sure that all functions are available from the keyboard (try tabbing from link to link).
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Users may become fatigued when using "puff-and-sip" or similar adaptive technologies.
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Provide a method for skipping over long lists of links or other lengthy content.
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Users may be using voice activated software.
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Voice-activated software generally cannot replicate mouse movement, so make sure that all functions are available from the keyboard.
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Users may not be able to control the mouse or the keyboard well.
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Voice-activated software generally cannot replicate mouse movement, so make sure that all functions are available from the keyboard.
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Users may not be able to control the mouse or the keyboard well.
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Make sure that your pages are error-tolerant (e.g. ask "are you sure you want to delete this file?"), do not create small links or moving links.
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| Challenges | Solutions |
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Users may become confused at complex layouts or inconsistent navigational schemes.
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Simplify the layout as much as possible.
Keep the navigational schemes as consistent as possible. |
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Users may have difficulty focusing on or comprehending lengthy sections of text.
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Where appropriate, group textual information under logical headings. Organize information in manageable "chunks."
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One method of input may not be sufficient.
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Where appropriate, supplement text with illustrations or other media, and vice versa.
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