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Re: Reference/Note tags

for

From: Duff Johnson
Date: Apr 18, 2025 1:59PM

Hi Philip,
> Thanks for the detailed response, Duff, confirming much, and clarifying and qualifying elsewhere. That's very helpful for folks like me who are trying to pin down some of the finer details of the standards and their implementations in various software and technology.
>
Happy to help!
> You make a good point about the difference between web pages and PDFs:
>
>> Unlike web pages, PDF files persist....Web pages can be fixed for everyone by a tweak and a reload. By contrast, PDF is often "delivered" rather than "served", so if it’s inaccessible on-delivery it’s generally inaccessible for every downstream user, forever.
>>
> In that context, I would note that the current widespread reliance on automated accessibility testing for PDFs tends to produce PDFs that will pass the PAC Tool or CommonLook Validator tests, without actually fully meeting all the PDF/UA standards. Many PDFs are adjusted to pass these testing tools, even where the testing tools may be not quite accurate.

I think it’s somewhat more complex… the tools are, generally, "accurate" for what they do… but they tend not to second-guess the human "checks" that remediators are supposed to be performing, in particular…

- correct logical reading order
- correct semantics, including representative heading structure

> Eventually, then, when software and screen readers are in place that process all these tags more fully, we will have a lot of PDFs that didn't ever really quite pass PDF/UA, but which only much later start to present annoying issues for users.

I’d like to see the tools get a lot more clever (and thus, aggressive) in helping users to identify "questionable" tagging… from the HUMAN checks perspective. I have hopes that AI will be of great help in this regard.

> Though the tests are getting better all the time, too.

Well, this is exactly why the PDF Association is publishing Techniques for Accessible PDF:

https://pdfa.org/techniques-for-accessible-pdf/

Our hope is that by establishing a rich (eventually, near-comprehensive) set of minimalist correct (and incorrect) PDF structures we’ll be "seeding" the necessary information to get everyone on the same, er, page. Watch out for the forthcoming release of new Techniques! #ShamelessPlug

Duff.