Level Access Accessibility Consultant James Thompson hosted the final webinar of an eight-part series on PDF Accessibility Basics on Thursday, January 4th on Accessibility Checker.
There were a few questions during the webinar that we did not have time to address, so we’ve provided the answers in this post.
For more information, you can access the webinar slides, transcript, and recorded presentation here: Accessibility Checker Webinar Resources. If you missed any of the prior webinars, you can access the resources for the entire PDF Accessibility Basics Series now.
Q: What happens if you right click and select Fix when the title fails?
A: Adobe Acrobat DC will open a dialog and allow you to enter the appropriate text.
Q: what is character limitation of alt text for images?
A: There is not definitive limit but I recommend keeping it terse, using the “Twitter rule,” less than 140 characters.
Q: What is the purpose of marking the figure as decorative? Do screen readers skip over images that are marked as decorative?
A: Marking the figure as decorative artifacts it and makes it invisible to assistive technology. If the figure does not contain information or contribute to the understanding of the page’s content then it should be made an artifact. Otherwise it should have appropriate alternative text of the image and, if is an image link, what activating the link will do or where it will go.
Q: The shading indicating the location of issues within the document appear above the actual item. Can that be changed?
A: The shading indicates where the object is in its layer. This can be fixed using Adobe InDesign sometimes, and technically it can be modified in Adobe Acrobat, but not a guarantee.
Q: Your document said no tags, so how do you add tags?
A: Tags can be automatically using the Auto-tag Document option in the Accessibility Tool or manually using the Reading Order Option. See the previous webinar about adding tags to PDFs.
Q: What is regularity in the Accessibility Checker?
A: Regularity describes the need for tables to have the same number of rows in each column and the same number of columns in each row. You can get this error when Adobe Acrobat does not recognize any column or role spans that may be in place and they should be double checked using the table editor as described in the webinar on Tables.
Q: If you have form fields within a table, do you label them as “form field”, or just TD?
A: The TD element should be around the form element. But screen readers may have issues if you use a table within a table. Make sure that there is only one level of table above the form field.
Q: Would you want to auto tag then make corrections?
A: For a simple page, auto-tagging is the best option but for complex pages with tables, building up the tags by hand may make more sense than trying to fix the auto-tagging. Try auto-tagging first but feel free to re-open the non-tagged version if retagging looks too cumbersome.
Q: Where can we download the Matterhorn’s Accessibility Checker? I am familiar with the protocol but never heard of the accessibility checker itself
Q: Is there a place where I can find the meaning of all the different tags… just one place
A: Joe Clark has a great breakdown posted on A List Apart here: https://alistapart.com/d/pdf_accessibility/PDFtags.html
Q: When I use the checker I sometimes get Table issues even though the document does not include a table. Can you explain?
A: If there are layout tables in the Content Panel you can get table errors even if you don’t have any tables in the Tags Panel.
Q: Quick question on accessibility of textbooks. Why doesn’t Adobe identify the page numbers? Cover is page 1 while Chapter 1 page 1 is identified as page 26 in the document?
A: The page numbers in Adobe Acrobat are calculated based on number of pages in the document and do not respect the page numbers of the document itself. When there is a discrepancy ensure that the document’s page numbers are tagged as text and consistently appear at the beginning or end of each page, not made artifacts. This will allow assistive technology users to identify pages.