Primary content does not conform to WCAG but alternate versions exist that do conform to WCAG. This technique can only be used if a technology makes it possible to create an accessible link to an alternate version.
This technique relates to:
The objective of this technique is to enable users to access alternate content that conforms to WCAG if the primary content, or the default content that users encounter when visiting a particular URI, does not conform. The alternate page, or conforming alternate version, may make some design or functionality compromises in order to conform, but must meet the requirements described in the definition in order to be a conforming alternate version. The definition of "conforming alternate version" is:
version that
conforms at the designated level, and
provides all of the same information and functionality in the same human language, and
is as up to date as the non-conforming content, and
for which at least one of the following is true:
the conforming version can be reached from the non-conforming page via an accessibility-supported mechanism, or
the non-conforming version can only be reached from the conforming version, or
the non-conforming version can only be reached from a conforming page that also provides a mechanism to reach the conforming version
Note 1: In this definition, "can only be reached" means that there is some mechanism, such as a conditional redirect, that prevents a user from "reaching" (loading) the non-conforming page unless the user had just come from the conforming version.
Note 2: The alternate version does not need to be matched page for page with the original (e.g., the conforming alternate version may consist of multiple pages).
Note 3: If multiple language versions are available, then conforming alternate versions are required for each language offered.
Note 4: Alternate versions may be provided to accommodate different technology environments or user groups. Each version should be as conformant as possible. One version would need to be fully conformant in order to meet conformance requirement 1.
Note 5: The conforming alternative version does not need to reside within the scope of conformance, or even on the same Web site, as long as it is as freely available as the non-conforming version.
Note 6: Alternate versions should not be confused with supplementary content, which support the original page and enhance comprehension.
Note 7: Setting user preferences within the content to produce a conforming version is an acceptable mechanism for reaching another version as long as the method used to set the preferences is accessibility supported.
When using this techique, placing a WCAG-conforming link to alternate content at the top of the page allows users to find the link quickly and to move to the conforming alternate version. To ensure users can always find the alternate version, regardless of where they enter the site, each page that does not conform at the specified level would include a link to the conforming alternate version.
On a Web site, for each page that does not conform to WCAG at the declared level, the first link on the page is called "Alternate version". The target of this link is the alternate version of the page that conforms to WCAG at the declared level.
Identify a page that does not conform to WCAG at the claimed conformance level.
Determine if the page contains a link to a conforming alternate version of the page.
Determine if the alternate version is a conforming alternate version of the original page and that it conforms to WCAG 2.0 at the claimed conformance level.
Both #2 and #3 are true.