PDF Tagging: The Major Key to Remediation

 In Articles, PDF Accessibility

Why Tagging Is So Important

For a PDF to be accessible to people who have disabilities and use assistive technology, as a baseline the document needs to be tagged. Of course, this is a complex topic, sometimes a daunting task, but hopefully we can help simplify it for you. In this article we’ll start at the root of the matter – why the PDF needs to be tagged in the first place, and we’ll answer some other common questions.

Tags are essential for PDF accessibility. They allow assistive technologies such as screen readers, braille keyboards, and other devices to detect what is being shown on the screen to someone who is blind or visually impaired. If that person is using some form of assistive technology to help them read a PDF, that technology isn’t actually looking at the content on the screen, it’s reading from the tags.  Consequently, if there aren’t any tags, there’s nothing to read. That said, some screen readers will use other components of a PDF to try to read to someone when tags aren’t present, but there are problems with this. First, without tags, the content in the document probably isn’t organized in a manner that assistive technology will read it accurately. Second, a lot of structural information gets lost. Third, according to accessibility standards, the tags are what assistive technologies are supposed to read from and, if there aren’t tags present, some assistive technologies won’t even try. Also, because document authors don’t know what technologies their audience will be using, the argument that,” X-Brand screen reader reads this ok” isn’t really ok.

Paragraph Tags Aren’t Always the Answer

When it comes to tagging, a question that often comes up is, “Why can’t I just put this in a Paragraph tag?” Knowing a little about how screen readers work might help answer this. As stated in the previous paragraph, assistive technology reads from the tags. Logically, if the text of the document is in a Paragraph tag, then a screen reader will read it. Screen readers, however, do so much more. For example, when they get to a Heading tag used to identify a new section in a document, they’ll announce the heading level. This helps people listening to the document not only know what section they’re in, but also helps them understand the document’s structure and organization. It answers questions like, “Am I in a completely new section or a sub-section of a bigger part?”  Tags are also useful for helping people navigate through a document quickly and easily.  For example, when headings are used correctly, someone using a screen reader can hear a heading for a section that they don’t want to read right then, skip over it, and move onto the next section. Similarly, consider this scenario: Someone with sight is talking about a document on “Stinging Insects” with someone without sight. The sighted person says, “In the section on Bumblebees, there’s a great list about all of the ways bumblebees communicate with each other.” This provides enough information so that the person without sight can navigate to the section on “Bumblebees,” and then search specifically for lists until they find the list about bumblebee communication. However, if everything is just placed in a Paragraph tag, all that navigational functionality is lost.

Fairness and Rules Matter

Along with being able to understand the structure, organization, and navigation of the document, it also comes down to “fairness.” If someone with sight can easily look at a page and see that there’s a list of five items, for example, it’s only fair that someone without sight also knows that there’s a list of five items there. And that’s how screen readers work. They tell their users, “List of five items,” for example and then they read the list. When the list is done, screen readers say, “Out of list.” Similarly, when they come to Table tags, screen readers announce, “Table of ‘X’ number of columns and ‘Y’ number of rows,” and then begin reading the table. This helps someone listening to the table know how it’s structured and organized. (This assumes the lists and tables are tagged correctly. Those are topics of future articles.)

Finally, there are “rules” when it comes to tagging PDFs, one being that the best (most accurate) tag is used for the content. Options include: <P> for paragraphs, <L> for lists, <Table> for tables, and <H#> for headings (the # being 1-6 based on the structure and hierarchy in the document). Other tags to consider using could be: <Caption> for figure or table captions, <Figure> for graphical elements, etc., that convey information, <Note> for foot/end notes, and <TOC> for tables of contents. There are more tags at the remediator’s disposal, if needed, and CommonLook provides training on “What tag to use, why, and when.”

Let the Dialogue Begin

We hope that this article has been helpful to begin the dialogue on why tagging is important, how tags are used, and “Why can’t I just put everything in a Paragraph tag and be done with it?”