Section 2.3: Relevant accessibility standards and guidelines
All 3 of the major accessibility standards and guidelines refer to the need for providing alternatives for non-text content such as images. Providing ALT text that is appropriate for the role of every image on the site, even if the text is empty (alt=""), and providing longer descriptions of images where needed will apply no matter which set of guidelines you choose to follow for your site.
Section 508
(a) A text equivalent for every non-text element shall be provided (e.g., via "ALT", "longdesc", or in element content).
Web Content Accessibility Guidelines 1.0
Guideline 1. Provide equivalent alternatives for auditory and visual content.
Checkpoint 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. [Priority 1]
Web Content Accessibility Guidelines 2.0 (Working Draft, 27 April 2006)
Guideline 1.1 Provide text alternatives for all non-text content
Success Criterion 1.1.1: For all non-text content, one of the following is true:
- If non-text content presents information or responds to user input, text alternatives serve the same purpose and present the same information as the non-text content. If text alternatives cannot serve the same purpose, then text alternatives at least identify the purpose of the non-text content.
- If the purpose of non-text content is to confirm that content is being operated by a person rather than a computer, different forms are provided to accommodate multiple disabilities.
- If non-text content is pure decoration, or used only for visual formatting, or if it is not presented to users, it is implemented such that it can be ignored by assistive technology.
