This checklist is based on the Accessible Electronic Documents Community of Practice (AED COP) of the Federal CIO Council developed guidance for Federal agencies to evaluate digital content for conformance to the Revised 508 Standards.
The NTL is looking for the following properties completed in PDFs:
Accessible PDFs include the following characteristics:
Navigational aids. Bookmarks, headings, and a table of contents assist all users in navigating the document Bookmarks are especially useful and can be created from document headings. These features can be accessed using the keyboard without relying on the mouse, and allow for multiple way for users to navigation content.
Document Structure Tags and Proper Reading Order. To read a document’s text and present it in a way that makes sense to the user, a screen reader or other text-to-speech tool requires that the document be structured. Document structure tags in a PDF define the reading order and identify headings, paragraphs, sections, tables and other page elements. The tags structure also allows for documents to be resized and reflowed for viewing at larger sizes and on mobile devices.
Headings are tagged with a heading tag. Heading tags match document headings and follow the visual outline. The tags follow the visual/logical order of the document
Alternative Text Descriptions for Non-Text Elements. Images and figures cannot be understood by the user of a screen reader unless there is alternative text associated with that image. Alternative text for images can aid many users, including those with learning disabilities. When screen reads encounter alternate text, they can interpret the element and read its alternate text description aloud.
There are additional characteristics of accessible documents including:
Use of color combinations that provides a sufficient degree of contrast and no reliance on color or sensory characteristics alone to convey meaning. Meaning of color or other sensory characteristics is duplicated in text. Text passes the Color Contrast Analyzer.
Lists are tagged correctly. Lists have a parent tag, and have one or more nested list item tags.
Data tables. Tables are identified with a “Table” tag. Table header cells have a “TH” tag and data cells have a “TD” tag.