The PDF/UA-1 Standard
The Matterhorn Protocol
Alternatively, the Matterhorn protocol can be used to check the conformity of PDF/UA. It is available for download from the PDF Association website. This document, which has also been translated into German, supports software developers and test persons in checking PDF documents for PDF/UA conformity.
It explains 136 error conditions, divided into 31 test points. These are in turn divided into 87 error conditions, which can be checked automatically by software. 47 Error conditions must be checked manually and interactively. 2 error conditions are not assigned.
The WCAG 2.0
The Web Content Accessibility Guidelines (WCAG) are the official guidelines of the W3C (World Wide Web Consortium) for accessible web content. These are now available in their second version from 2008 and describe how the content of websites can be created barrier-free using the relevant markup and programming languages.
Since the PDF is also mentioned as an example of the possible web content, most of these guidelines also apply to PDF documents. Since accessibility was not reinvented with the PDF/UA standard, it is based on the WCAG.