Tagging Document Structure
Tagging provides a way to identify the semantic structure of a PDF document for use by assistive technologies
and other technologies like search engines to identify the main topics and strcutural relationships of content in a PDF document.
Benefits to People with Disabilities
- People with disabilities can navigate the structure of the document
Benefits to Everyone
- Search engines can use headings, text descriptions and other tags to improve search results
Benefits to Developers
- Content will be more accurately be represented on the web, increasing the relavence search results to your web resources
Related Accessibility Requirements
- § 1194.22.g Row and column headers shall be identified for data tables.
- § 1194.22.h Markup shall be used to associate data cells and header cells for data tables that have two or more logical levels of row or column headers.
- § 1194.22.a A text equivalent for every non-text element shall be provided (e.g., via "alt", "longdesc", or in element content).
Illinois Information Technology Accessibility Standards
- 1.3 Provide meaningful page titles.
- 1.4 Use headings to introduce sections and sub-sections, and use them in the correct order.
- 1.5 Use lists to identify series of related items, including navigation menus.
- 11.1 Identify a header cell for each column and row in simple data tables.
- 11.2 Identify relationships in complex data tables using id and headers attributes.
- 4.1 Provide appropriate "alternate text" for all images.
- 4.2 Provide full descriptions for graphs, diagrams, and other meaningful images.
Web Content Accessibility Guidelines (WCAG) 2.0
- 2.4.2 Page Titled
- 2.4.10 Section Headings
- 1.3.1 Info and Relationships
- 1.1.1 Non-text Content
- 4.1.2 Name, Role, Value: For all user interface components (including but not limited to: form elements, links and components generated by scripts), the name and role can be programmatically determined; states, properties, and values that can be set by the user can be programmatically set; and notification of changes to these items is available to user agents, including assistive technologies.
Web Content Accessibility Guidelines (WCAG) 1.0
- 3.5 Use header elements to convey document structure and use them according to specification.
- 3.6 Mark up lists and list items properly.
- 5.1 For data tables, identify row and column headers.
- 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.