This is a straightforward distillation of the WAI guidelines, highlighting Priority 1 issues that must be addressed to reach the 'A' standard. It's based on the official WAI guidelines, dated May 5, 1999.
1.1 Provide a text equivalent for every non-text element (e.g., via "alt", "longdesc", or in element content). This includes: images, graphical representations of text (including symbols), image map regions, animations (e.g., animated GIFs), applets and programmatic objects, ascii art, frames, scripts, images used as list bullets, spacers, graphical buttons, sounds (played with or without user interaction), stand-alone audio files, audio tracks of video, and video.
1.2 Provide redundant text links for each active region of a server-side image map.
1.3 Until user agents can automatically read aloud the text equivalent of a visual track, provide an auditory description of the important information of the visual track of a multimedia presentation.
1.4 For any time-based multimedia presentation (e.g., a movie or animation), synchronize equivalent alternatives (e.g., captions or auditory descriptions of the visual track) with the presentation.
2.1 Ensure that all information conveyed with color is also available without color, for example from context or markup.
4.1 Clearly identify changes in the natural language of a document's text and any text equivalents (e.g., captions).
5.1 For data tables, identify row and column headers.
5.2 For data tables that have two or more logical levels of row or column headers, use markup to associate data cells and header cells.
6.1 Organize documents so they may be read without style sheets. For example, when an HTML document is rendered without associated style sheets, it must still be possible to read the document.
6.2 Ensure that equivalents for dynamic content are updated when the dynamic content changes.
6.3 Ensure that pages are usable when scripts, applets, or other programmatic objects are turned off or not supported. If this is not possible, provide equivalent information on an alternative accessible page.
7.1 Until user agents allow users to control flickering, avoid causing the screen to flicker.
8.1 Make programmatic elements such as scripts and applets directly accessible or compatible with assistive technologies [If functionality is important and not presented elsewhere, otherwise level Double-A.]
9.1 Provide client-side image maps instead of server-side image maps except where the regions cannot be defined with an available geometric shape.
11.4 If, after best efforts, you cannot create an accessible page, provide a link to an alternative page that uses W3C technologies, is accessible, has equivalent information (or functionality), and is updated as often as the inaccessible (original) page.
12.1 Title each frame to facilitate frame identification and navigation.
14.1 Use the clearest and simplest language appropriate for a site's content.
Also see the Tinhat page: Simple WAI level 'A' checklist, where the guidelines are described in simpler but less precise language.
This page is valid XHTML to WAI Double-A standard
Copyright for the WAI excerpt © 1999 World Wide
Web Consortium, (Massachusetts Institute
of Technology, European Research Consortium
for Informatics and Mathematics, Keio
University). All Rights Reserved. http://www.w3.org/Consortium/Legal/2002/copyright-documents-20021231
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Comment on DRC Report
Simple WAI level A checklist
Level A -
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Tips for web editors
Non-HTML files (PDFs) and accessibility
Gov guidelines for UK gov sites (intro)