In general terms, accessibility is used to describe the degree to which something is available to as many people as possible. However, it is often used to focus on people with disabilities and their right of access to entities. Assistive technologies are helping the people with special needs in all the areas of life. This is true in the field of computer and internet as well, so that this technology could also be made accessible to the people with disabilities.
While making the computers and web accessible to the people with such special needs, it is important to make the contents and data accessible to the users; PDF files are also part of these contents. When we want to make a PDF accessible, it means we need to follow certain standards while creating or editing PDF files, so that the contents of these PDF files can be accessed by the assistive technologies and provided to the users.
These standards include making the contents completely tagged and marking the document tagged as well, defining document language, providing accessible font encoding, bookmarks, and consistent heading structure etc. You can find more details about accessible PDF files in section 14.9 of PDF Specification Reference. And in order to understand the accessibility for the contents published on the web, you need to check out W3C document Web Content Accessibility Guidelines.
We have seen a little bit about accessibility and accessible PDF files. Now, let’s have a look at a free tool, called PAC (PDF Accessibility Checker) , provided by “Access for All” Foundation. This is a very simple tool to test the technical accessibility of the PDF documents. You only need to download and extract the tool, and run PAC.exe to check the PDF.
Simply browse the PDF file you want to test for accessibility and press Start Check button. It will show you all the passed results in the testing criteria.