HTML Quick Reference - HTML5 and CSS Comprehensive - page 638

§ 1194.22 (m) When a Web page requires that an applet, plug-in, or other
application be present on the client system to interpret page content, the page must
provide a link to a plug-in or applet that complies with 1194.21 (a) through (l).
Anyappletorplug-inthatisusedonyourWebpagesshouldalsocomplywith
Section508.TheWebdevelopershouldprovidealinktotheappletorplug-inthatis
compliant with Section 508.
§ 1194.22 (n) When electronic forms are designed to be completed on-line,
the form shall allow people using assistive technology to access the information,
field elements, and functionality required for completion and submission of the
form, including all directions and cues.
Forms need to be accessible to anyone, including those using nonvisual browsers.
You should therefore include value attributes or alternative text for buttons, input boxes,
and text area boxes on any form included on your Web page.
§ 1194.22 (o) A method shall be provided that permits users to skip repetitive
navigation links.
It can be helpful to provide text links at the very top of a Web page so that users of
nonvisual browsers can quickly link to the content of the Web site. Some Web developers
use a link that allows users to skip to the main content of the Web page immediately by
using a transparent image.
§ 1194.22 (p) When a timed response is required, the user shall be alerted
and given sufficient time to indicate that more time is required.
Usersneedtobegivensuficienttimetoreacttoatime-outfrominactivityby
notifying users that the process will soon time out. The user should then be given a way
to easily request additional time.
WAI Guidelines
The WAI identifies 12 guidelines for Web developers, known as Web Content Accessibility
Guidelines (WCAG) 2.0. The Web Content Accessibility Guidelines (WCAG) documents
explain how to make Web content more accessible to people with disabilities. Web content
generally refers to the information in a Web page or Web application, including text,
images, forms, sounds, and such. All Web developers should review the information at
the official Web site at w3.org/WAI/intro/wcag.php for complete information on these
guidelines, and should apply the guidelines to their Web page development.
The 12 WCAG 2.0 guidelines are organized under four principles: perceivable,
operable, understandable, and robust. Anyone who wants to use the Web must have
content that is:
Perceivable: Information and user interface components must be presentable to
users in ways they can perceive. Users must be able to perceive the information being
presented (it can't be invisible to all of their senses).
Operable: User interface components and navigation must be operable. Users must
be able to operate the interface (the interface cannot require interaction that a user cannot
perform).
Understandable: Information and the operation of the user interface must be
understandable. Users must be able to understand the information as well as the operation
of the user interface (the content or operation cannot be beyond their understanding).