Does this mean that all pages have to be displayed in black and white?
No, this provision does not prohibit the use of color to enhance identification of important
features. It does, however, require that some other method of identification, such as text labels,
must be combined with the use of color. This provision addresses not only the problem of using
color to indicate emphasized text, but also the use of color to indicate an action. For example, a
web page that directs a user to "press the green button to start" should also identify the green
button in some other fashion than simply by color.
Is there any way a page can be quickly checked to ensure compliance with this
provision?
There are two simple ways of testing a web page to determine if this requirement is being met:
by either viewing the page on a black and white monitor, or by printing it out on a black and
white printer. Both methods will quickly show if the removal of color affects the usability of the
page.
(d) Documents shall be organized so they are readable without requiring an associated
style sheet.
What are the potential problems posed by style sheets?
Style sheets can enable users to define specific viewing preferences to accommodate their
disability. For instance, users with low vision may create their own style sheet so that,
regardless of what web pages they visit, all text is displayed in an extra large font with white
characters on a
black background. If designers set up their pages to override user defined style sheets, people
with disabilities may not be able to use those pages. For good access, therefore, it is critical that
designers ensure that their web pages do not interfere with user defined style sheets.
In general, the "safest" and most useful form of style sheets are "external" style sheets, in which
the style rules are set up in a separate file. An example of an external style sheet is:
Example of source code: (e) Redundant text links shall be provided for each active region of a server side image
map.
How do "image maps" work?
An "image map" is a picture (often an actual map) on a web page that provides different "links"
to other web pages, depending on where a user clicks on the image. There are two basic types
of image maps: "client side image maps" and "server side image maps." With client side image
maps, each "active region" in a picture can be assigned its own "link" (called a URL or "Uniform
Resource Locator") that specifies what web page to retrieve when a portion of the picture is
selected. HTML allows each active region to have its own alternative text, just like a picture can
have alternative text (see 1194.22(a)). By contrast, clicking on a location of a server side
image map only specifies the coordinates within the image when the mouse was depressed.
The ultimate selection of the link or URL must be deciphered by the computer serving the web
page.
Why is this provision necessary?
National GACC Website and GACC Website Template
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Implementation Guidelines