The PDF Accessibility Liaison Working Group (LWG) and its importance for the accessibility of PDFs

In the future, we want to give you regular insights behind the scenes of the LWG. So stay tuned if you want to know what the working group is currently working on and which examples are discussed. Today, we will first take a look at what the LWG actually is and what it fundamentally works on.

The increasing digitization brings numerous advantages, but also challenges. One of the biggest challenges: digital documents can often not be read by everyone. For instance, people with visual impairments who rely on screen readers need accessibility to read documents independently, such as invoices or bank statements. PDF documents are widely used and can be found almost everywhere on the internet. The LWG systematically addresses the specific challenges of PDF accessibility.

The LWG aims to provide systematic support for the challenges of creating accessible PDFs. The focus is set on the collaboration among various stakeholders, including technology companies, accessibility experts, and institutions advocating for the rights of people with disabilities.

The starting point is always a concrete example for which a solution is sought. The development of techniques incorporates standards such as the PDF standards, PDF/UA standards, and guidelines like the Web Content Accessibility Guidelines (WCAG).

As a company committed to accessibility, axes4 supports the advancement of standards for accessible PDFs. Markus Erle (founder of axes4) and Jochen Fehling (axes4) are, alongside Birgit Peböck (Barrierefrei PDF OG), the chairs of the working group. Participation in the LWG is open to all members of the PDF Association, accessibility professionals, and users. You can register by emailing Jochen Fehling (j.fehling (at) axes4.com).

In its work, the LWG distinguishes between Use Cases and specific examples, which are the actual techniques. The techniques are thus compiled for a specific use case, such as the basic requirements (listed below).

An example of a technique: How do I create a linked table of contents?

A technique consists of:

1. A testing procedure with multiple checkpoints so you can easily verify whether your specific implementation of the recommended technique meets the criteria.
2. A brief description.
3. An example PDF.
4. Additional metadata, such as a reference to the Matterhorn Protocol or the WCAG.

Over several years, the LWG has worked on the five basic requirements for techniques for PDF accessibility. For each of these requirements, Markus Erle has written a blog post (in german):

• Basisanforderung 1: Die grundlegenden technischen Regeln sind eingehalten.
• Basisanforderung 2: Textinhalte sind maschinenlesbar
• Basisanforderung 3: Realer Inhalt wird von Artefakten unterschieden
• Basisanforderung 4: Die Logische Inhaltsreihenfolge ist definiert
• Basisanforderung 5: Angemessene Semantik