PDF stands for Portable Document Format and is a common internet file format. It's used for electronic distribution because it keeps the look and feel of the original document, including the fonts, colours, images, and layout.
Sharing a file in PDF format allows anyone to view the document, regardless of what word processor was used to create it. More importantly, it prevents formatting errors from cropping up due to word-processor incompatibilities, making PDFs a must for official documents like resumes and important letters.
However, PDF files make your content harder to find, use and maintain. It can also be difficult for users to customise them for ease of reading, and often they do not work very well with assistive technologies like screen readers.
Therefore, where possible, publish the document as an HTML web page. It is the best way to reach as many people as possible.
Here are instances when it is recommended to export your document as a PDF:
- important documents that are to be shared with anyone external to the University
- graphic design development in which team members are working at a distance and need to explore design ideas online
- the online distribution of any printed document in which you want to preserve its printed appearance.
When publicly distributing written PDF documents online, you should use the University branded Microsoft Word templates that can be downloaded from the corporate identity pages.
When producing PDF documents for internal office use, decorative images should only be used sparingly if at all.
Images that convey useful information must have text alternatives (or “Alt text”).
Decorative images and repeated headers and footers should be removed from the reading order so that screen readers and other assistive technologies ignore them.
Check a PDF for accessibility
You should check that your PDF is accessible before publishing it.
You can pick up many accessibility issues by running some automated tests on your document.
You’ll also need to manually test your document to check that it fully meets accessibility standards. Use the accessibility checklist created by 18F (the US government’s digital agency) to help you with your manual testing.
To check that your PDF is accessible, you can use Adobe Reader or Adobe Acrobat Pro. You should also test your PDF is accessible using a screen reader.
You can use Adobe Reader to find out if your PDF document is correctly tagged and structured. People using screen readers need these to be able to access your document.
Go to ‘Edit’ then ‘Accessibility’ and select ‘Quick check’. To fix any issues, you’ll need to either fix the original document in Word or use Adobe Acrobat Pro.
Adobe Acrobat Pro
Follow Adobe’s instructions on using Acrobat Pro to check if your PDF is accessible.
The PDF should pass the full check for WCAG Level AA without any warnings.
Quick screen reader check
If you’re using Windows
Non Visual Desktop Access (NVDA) is a free open source screen reader for Windows. It can be installed to the desktop or run from a portable USB drive.
With NVDA running, open the PDF and use the following commands to check the PDF:
- From the top of the PDF (with the numlock off), use Numpad 0 + Numpad 2 to read the PDF from top to bottom and check the reading order.
- Use the tab key to move through the PDF and check the tab order.
- Use the h key to move through the PDF and check the heading structure.
- Use the g key to move through the PDF and check for text descriptions.
These commands will also work with the JAWS screen reader from Freedom Scientific.
If you’re using a Mac
All Apple Macs have VoiceOver built in. Turn VoiceOver on (or off again) using Command + F5. With VoiceOver running, open the PDF and use the following commands to check the PDF:
- From the top of the PDF, use a double finger down swipe, or ‘Control + Option + a’ to read the PDF from top to bottom and check the reading order.
- Use the tab key (repeatedly) to move through the PDF and check the tab order.
VoiceOver does not provide shortcut keys for navigating by headings or graphics.