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Manual testing is critical to fully check for accessibility. Automated tools have limitations. For example, they can’t tell if the alt text for an image is accurate or informative, or . Screen readers also cannot tell if the correct tags have been used for each content item.
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PDF remediation should never be considered complete until the document has been thoroughly tested using a screen reader. It’s not required to use more than one screen reader. However, but it is recommended to use at least two, since . This is because there can be differences in behavior between assistive technologies.
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Testing for PDF accessibility on a Mac using VoiceOver (the built-in screen reader), or on mobile devices, is not the best idea. Unfortunately, both VoiceOver and built-in mobile screen readers have more limitations limits when it comes to PDF, so your PDFs. Your best bet is to use either NVDA or JAWS on Windows.
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Screen readers are capable of reading many different languages. So you need to be sure that your PDF has the correct language used. If you have an English document but you have Acrobat set for French, the screen reader will be very confused and unable to read your content correctlyA document in English will not be read correctly if Acrobat is set to read French or another language.
Go to File and click Properties.
In the Document Properties Box, select the Advanced Tab.
In the Reading Options section, select a language from the Drop-Down menu.
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When you move items around in the Order Pane and , the tags in the Tag Pane move correspondingly, sometimes they . Sometimes, when objects are moved, their tags may be inadvertently moved inside other tagsmoved into the wrong place.
When you change the order of items in the Order Pane, the visual stacking order of items also changes. You might end up with an object that should be in front of another object but ends up behind it, causing layout problems. You’ll need to fix the order.
The numbering you see in the Order Pane does not relate to the screen reader reading order. Instead, it shows the visual stacking order of different content layers. So don’t be misled by these numbers when you’re checking for screen reader reading order.
In some cases, it's not possible to manage the reading and display order of multiple tags. This is the case for tags that are next to each other from the Order Pane. If this happens, you’ll need to go into the Tags Pane to make fixes.
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Tags are predictably read by screen readers from top to bottom in the tag tree (in the order in which they appear).
When manually tagging, create the tags in the order in which you expect the content to be, since they are added one after the other. This will minimize any tag rearranging. But if you need to move tags around, just drag and drop them in the Tags Pane.
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