My apologies for once again returning to this topic but, when checking PDFs for accessibility it is not OK to just run them through an automated accessibility checker and then publish if the checker finds no issues. And yet, so many organisations still fall into the trap of doing precisely this.
Running a PDF though and automated accessibility checker will tell you at best 20% of what you need to know about the accessibility of a document. It is quite common for documents that pass a checker to contain many accessibility problems, including really serious ones.
This is because automated checkers can only test for a small sub-section of potential problems and hence return potentially hundreds of Type 2 errors (false negatives, or failing to identify an actual problem). They can also occasionally return a small number of Type 1 errors (false positives, or telling you there’s a problem when there isn’t).
Simple but wrong
It is of course an attractive idea that you can simply press a button and get a Yes or No answer as to whether the document is accessible or not. But it’s just not reality.
This does not mean your document is accessible.
And neither does this.
There is a famous cartoon by the American cartoonist Wiley Miller (Wiley Ink) depicting a signpost pointing to the left labelled ‘simple but wrong’, and another pointing to the right labelled ‘complex but right’. A long queue of people is shown heading off to the left (and subsequently over a cliff), while only one or two people choose the path to the right. This scene could of course describe many different situations in life. Over-reliance on automated accessibility checkers is just one of them.
The right way to check a PDF for accessibility
To be as sure as you can reasonably be expected to be that a PDF is accessible you need to do 3 things.
- A manual check against the WCAG standard
- A check with an automated checker
- Testing with multiple assistive technologies (not just screen readers)
Learning to test
With a little over one hour’s instruction even beginners can learn how to thoroughly test a PDF for accessibility. Our Accessible PDFs from InDesign 2-day Masterclass and our Accessible PDFs from Acrobat course both include as standard a module on how to test correctly, including how to use a screen reader and other assistive technologies. This testing module can also be included in the Accessible PDFs from Word course if required.