In December 2008, the Web Accessibility Initiative (WAI)
published a set of guidelines that were 4 years in the making. WCAG
2.0 replaced the long-standing WCAG 1.0 guidelines that were
published in 1999.
The guidelines are quite comprehensive and are an excellent
place to start with accessibility. When followed in tandem with
user experience testing, a good accessible web product can be
The guidelines cover things such as providing alternative text
for images and ensuring access for people using keyboard-only
controls or assistive technologies such as screen readers (
description of screen readers on Wikipedia (this
link will open in a new browser window))
There are 3 levels of conformity to the guidelines which are
referred to as A, AA, and AAA that represent different levels of
access and usability.
These guidelines need to be followed in order to make content
accessible to end users and deciding to what extent the guidelines
will be adhered to is a part of the BS 8878 process.
The Authoring Tool Accessibility Guidelines (ATAG) also created
by WAI help developers build authoring tools that are accessible to
disabled users, and that output accessible content.
User Agent Accessibility Guidelines (UAAG), guide the accessible
development of browsers and assistive technologies that are used to
view web-pages. Conformance to UAAG helps to ensure that user
agents are compatible with Assistive technologies.
Guidelines for Rich Internet Applications (RIAs)
Rich Internet Applications are those types of applications found
on the web that deliver a richer experience than is offered by HTML
alone. RIAs typically use HTML in combination with other web
(AJAX), Flash or Silverlight.
The RIA experience for the user tends to be more like a desktop
Because of the way that information is served (dynamic rather
than static) and the technologies used, RIAs present specific
challenges. WCAG 2.0 guidelines have been written with RIA in mind.
The criteria for conformance applies to RIAs as much as they do to
You can get a head start on accessible RIA by using components
that have been designed to be accessible:
WAI also publish guidance on accessible RIA development:
Non-British guidelines (e.g. Section 508)
There are some other guidelines such as Section
508 (this link will open in a new browser
window) in the states that products may be developed to.
Note that these guidelines typically require a lower level of
conformance than more recent guidelines such as WCAG 2.0.
Section 508 is currently being updated and slated for release in