Document and PDF Accessibility: The Basics

1.What is an accessible PDF?

A PDF document is considered truly accessible if it can be used/accessed by all users, including people with disabilities. For a PDF to be considered accessible, it should be compliant to accessibility standards, including WCAG 2.0, WCAG 2.1, Section 508, and PDF/UA. While it is technically possible for a PDF to be accessible and not meet the accessibility standards, only the most basic of documents would apply. The standards were developed to ensure that documents work well with screen readers and other assistive technology.

2.What is the difference between PDF and accessible PDF?

An accessible PDF document can be navigated and accessed by everyone, including people with disabilities; this includes access for people who are blind, visually or cognitively impaired, or color-blind. If a PDF document is not created or remediated for accessibility to everyone, it is considered inaccessible.

3.How to check if a PDF is accessible?

To check if a PDF is accessible, you can use CommonLook PDF Validator - A 100% FREE and complete plugin for testing and verifying PDF Accessibility.

4.What Is PAC?

PAC stands for PDF Accessibility Checker. It was initially released in 2010 and was the first automated PDF/UA compliance validation tool. Having had three previous versions before PAC 2021, PAC is designed to easily identify all of the machine verifiable success criterion of ISO 14289-1 (PDF/UA) and WCAG (Web Content Accessibility Guidelines).

5.What is a PDF Accessibility Checker? What does it really do?

Document and PDF Accessibility: Technical

1.What are Tags in PDF?

Tags provide assistive technologies with an outline or structure of the PDF that interprets the content and its reading order to users. This outline is hidden from sighted viewers unless they open up the tag sidebar menu.

2.What is a Tagged PDF?

A tagged PDF is a PDF document that contains tags. Tags provide a logical structure that governs how the content of the PDF is presented through assistive technology. A properly tagged PDF, therefore, becomes accessible to everyone. Aside from making the PDF accessible, a tagged PDF has a few other advantages. For example, the content of a tagged PDF reflows seamlessly on devices with smaller screens, like smartphones and tablets.
A tagged PDF helps keep track of where items are in a particular document. This simplifies the review of workflows in documents.

3.What is PDF reading order?

Reading order is the order or sequence that assistive technologies (AT), like screen readers, present content to consumers. The tags in a PDF, or the Tags tree, present the logical structure of the document.
The tag tree also includes the tag types that we all know and love – Headings, Lists, Tables, Figures, etc. By itself, this does not dictate reading order.

4.How to tag lists in PDF?

Tagging lists properly in a PDF is important. And sometimes it’s difficult. For example, when a screen reader finds an (list) tag in the Tags tree, it will inform the user of the existence of a list, how many items are in the list and when the list has ended. It is much easier to skip list tags and just leave the content in paragraph tags, but this is not only semantically inaccurate but it also negatively impacts the end user's experience.