This last special case was included in the Section 508 Standards as a "last resort method for bringing a Web site into compliance with the other requirements in Â§1194.22."
A text-only page, with equivalent information or functionality, shall be provided to make a Web site comply with the provisions of this part, when compliance cannot be accomplished in any other way. The content of the text-only page shall be updated whenever the primary page changes.
If you must resort to providing a text-only alternative page, you must ensure the following:
Note: Alternative pages are generally updated less often than "primary" pages. An out-of-date page may be as frustrating as one that is inaccessible because, in both cases, the information presented on the original page is unavailable. Automatically generating alternative pages may lead to more frequent updates, but you must still ensure that generated pages make sense, and that users are able to navigate a site by following links on primary pages, alternative pages, or both. Before resorting to an alternative page, reconsider the design of the original page; making it accessible is likely to improve it for all users.
Several sites are adopting an automatic generation of text-only sites using a tool called "Betsie" which stands for BBC Education Text to Speech Internet Enhancer.
According to the Betsie site:
"Betsie makes various changes in the HTML code of the page - removing all the images and the unnecessary formatting, so that what you get sent is the text content of the page, unmolested and at the top, with all the links on the BBC Navigation Bar moved to the bottom, so they aren't the first thing you have to deal with every time."
The results of the Betsie transformation are very similar to what a user sees of the site with IBM Home Page Reader. The Betsie script is available for downloading.
It is rarely the case that a page cannot be made accessible, so that the hypothesis of Â§1194.22(k) (when compliance cannot be accomplished in any other way) is not met. Providing so called "text-only" alternatives is rarely justified by the 508 standards. Furthermore, the transformations used by Betsie require that the page be accessible anyway, such as having alt-text on images and labels on forms.
There is one commercial offering for creating text only versions, and that is from Usable Net. At this writing, you can see what the transcoder does at the National Science foundation web site. They offer a link to the transcoded version of the site as alt-text on an invisible image at the top of the page.