The accessibility, or otherwise, of PDF (Portable Document Format) files is something of a bone of contention within the accessibility community, and an ongoing source of frustration among those working to improve document accessibility in their own organisation or industry.
The document format can be complicated to make accessible, and has many known issues—such as being difficult to correctly tag page elements, being incompatible with screen reading software, and jumbling up the read order from the source file.
But, imagine the accessibility challenge that occurs when you embed an inaccessible Illustrator file inside a PDF then try to make the whole document accessible.
Let’s illustrate this with an example.
The problem: an Illustrator map inside a PDF brochure
A state transport authority creates a map of a train network in a major city. That map, created using an application such as Adobe’s Illustrator, shows the layout of lines and stops, interchanges between lines and ticket zoning, then exports it as a PDF.
The agency imports this map to an Adobe InDesign file providing written information about each station, connecting transport services, platform information and accessible entrances and exits. It then exports this whole document as a PDF to be hosted on a public transport website.
Being a government body, the agency needs to make its documents accessible to everyone, including people with a disability. That means tagging headings, paragraphs and other page elements so that they can be correctly identified by assistive technology—in particular, screen reading software.
But, there’s a problem: the Illustrator line map cannot be tagged, because it’s a singular image created in Illustrator. The only solution—if accessibility hasn’t been considered from the very beginning—is to create a very long and cumbersome alternative text description of the entire map.
That’s an inelegant solution to a real accessibility issue. And remember, maps are used in all sorts of documents in all sorts of industries. Just think about building evacuation plans, electoral and property boundary information, development applications, construction and site plans, venue seating information, and festivals and other public events, to name a few.
As we mentioned above, the best way to address Illustrator within PDF accessibility issues is to start at the beginning, with the creation of the map or other illustration—in this case, done in Adobe Illustrator—that will be used later in a PDF document.
While a visual representation of a transport system, as in this example, is highly relevant to the majority of end users, the creation of a plain text version that describes each line’s station order, interchanges with other lines and geographic divisions (ticket zoning) is the logical accompaniment for people unable to view the map. This information’s online location should be referenced in the map’s alternative text as well as in the appropriate webpage text for the PDF link itself. An audio version for each line could also be supplied. A transport audio guide [link is external] produced by Transport for London can be listened to as an example.
In our working example, we came across another issue that required a solution. When exported to PDF we found that screen reader software was reading out the map text (e.g. line and station names) in an illogical order that followed a traditional left to right, top to bottom of page format, rather than each line’s station order.
The accessibility approach here should be to ensure that any text elements within the Illustrator file are selected and converted to Outlines under the Type menu.
If the image has already been created and exported as a PDF and you do not have access to the original Illustrator file, the approach should be to create artefacts of all the text elements that the screen reader is announcing in the Acrobat Contents Panel.
As a caveat, these are approaches which have worked for us, but may not work for you. If that’s the case, why don’t you share your situation below. Or, if you have a solution, share your approach.
If you are looking for professional document remediation services for your organisation you can also contact Media Access Australia’s web accessibility service, Access iQ.