PDF files are commonly used to share information, but they can often be inaccessible to people with disabilities. PDFs are not always readable by screen readers or other assistive technologies. Testing a PDF for accessibility is essential to ensure that it can be used by everyone. There are several ways to do this. This article will tell you which ones.
PDF accessibility, a key component of digital accessibility
similarly to website accessibility, PDF document accessibility aims at making digital content accessible to all users. The benefits: customer experience, inclusion, visibility, reputation/brand image, economic potential… Without forgetting compliance with legal requirements.
The best way to create a more inclusive online space and therefore – in a global sense – reap the benefits is to test the accessibility of PDFs.
What should be checked when creating accessible PDF files?
Reading order
A logically structured document with a clear reading order.
Structuring the document
To guarantee the accessibility of a PDF, start by structuring the document using a tagging process to mark headings, paragraphs, lists, images, tables, etc.
Check the logical order
Each element should follow a logical reading order to make navigation easier for all users. Using the appropriate tags will help to maintain this order and ensure better understanding.
Alternatives
Images in the PDF should have alternative descriptions that explain their content to screen reader users.
- Add descriptions for informative images
- Include clear captions for tables
- Use accessibility tags
Headings
Headings play an important role in navigation.
- The use of heading styles helps to structure the document effectively.
- It is important to respect the hierarchy of headings, from the main title to the sub-titles.
Other key elements
- Use legible fonts
- Ensuring sufficient contrast between text and background improves legibility, particularly for people who are colour blind
- Include clear descriptions/titles for links – allow users to understand where they are being taken when they click on them
- Create forms that are accessible to screen reader users
Steps to follow and accessibility testing methods for PDF
Built-in checking tools
Microsoft Office and Adobe Acrobat have integrated checking tools that analyse PDF files and identify common accessibility problems. These tools are a good starting point, but they cannot detect all issues.
Manual testing by experts
For a more thorough evaluation, you can also manually test a PDF for accessibility by following these steps:
- Open the PDF in a screen reader using Acrobat Reader
- Convert the PDF to text
- Check that the content is easy to understand
- Check the color contrasts used and the legibility of the fonts.
Note: This method can be off-putting and lead to errors
Real-world testing with support tools – user testing
Testing the PDF in real-world conditions helps to identify problems that automated tools may miss. This includes testing with screen readers/text-to-speech software and other assistive technologies commonly used by people with disabilities.
Specific accessibility checkers PAC 2021
PAC 2021
The PAC 2021 is a reliable tool. It checks tags, links and reading order. However, it has limitations.
PAC 2021 does not always detect complex errors and all non-conformities. It is difficult to identify the exact cause of problems. Image descriptions may go unnoticed. Colour contrast analysis is basic.
For all these reasons, it is essential to combine PAC verification with manual inspection.
Vera PDF
Vera PDF can be used to check compliance with accessible PDF standards.
Like PAC 2021, Vera PDF provides a good place to start analysing PDF but it has analytical and practical limitations. Users often need to make manual adjustments.
The DocAxess Accessibility Checker
The DocAxess checker is an alternative solution to the limitations of traditional tools. Powered by AI, it provides more advanced and reliable PDF analysis.
- Complete analysis by PDF accessibility requirements
- Precise error detection + suggestions for concrete solutions to improve PDF accessibility
- Advanced features: form analysis, colour contrast check, etc.
- Advanced semantic understanding: uses AI to understand the meaning of content and identify contextual issues.
- Accurate screen reader simulation: takes into account different environments and user configurations.
- Extensive customisation options: tailor tests to meet specific needs and regulatory requirements.
The reference standard for passing the test
The PDF/UA standard is the benchmark for testing PDF accessibility. Following the guidelines of ISO 14289-1 is essential to ensure compliance. This standard defines the criteria for making PDFs accessible to everyone, including those using assistive technology.
PDF accessibility testing is an essential step towards digital inclusion. By applying the solutions described in this article, you can resolve accessibility issues in your PDFs and create documents that everyone can use. In doing so, you will contribute to a more inclusive society.
Remember: Accessibility is an ongoing process. It is important to test your PDF regularly to make sure it stays available.
