Best practice on making an accessible PDF and how to make an existing PDF more accessible.
You should publish most content as web pages (sometimes known as HTML pages) on GOV.WALES. This means that everyone can use our website.
If you intend to publish a PDF, first check whether you can use a PDF file.
If you have to publish content as a PDF file, it can be made more accessible if you follow this advice.
Improving the accessibility of a new PDF file
PDF is a destination format. PDF files begin in other applications, such as desktop publishing and word processing programs or as another file type. In the case of scanned documents they will typically begin as a TIFF file.
You should maximise the accessibility in the source document before outputting as a PDF file.
The basic guidelines for non-HTML documents should always be followed.
In addition to the basic guidelines for non-HTML documents, you should:
- use tools and techniques that will result in the production of accessible PDF documents
- use the facilities (if available) in the authoring application to add meaningful alternative text to any graphics
- use the word processor to specify heading levels and other styles to identify document elements such as titles and headings
- avoid bolding and changing the font and size of text to create the visual appearance of heading levels and other structural elements
- use the word processor or design package’s inbuilt table editor for tabular information (if available)
- if possible, select products that provide authors with the option to export tagged accessible PDF. This will reduce the amount of time verifying structure after the PDF is produced
- if creating a PDF by scanning a paper document, submit the content to Optical Character Recognition (OCR). Then add the necessary accessibility components prior to distributing the PDF file. For more help see improving the accessibility of an existing PDF file
- if you intend to use the PDF as an interactive document or form, add form fields and other controls with appropriate short descriptions
If you're using Adobe InDesign follow creating accessible PDFs (on adobe.com).
Improving the accessibility of an existing PDF file
If a PDF file is created without following accessibility guidelines, it may need changes to improve its accessibility.
PDFs created by scanning a printed page
Perform optical character recognition (OCR) on documents that were created as a result of scanning a document
Interactive documents or forms
Add form fields and other controls with appropriate short descriptions for the form elements and controls.
A PDF must have a structure by being “tagged”. If it has not been tagged, add tags to the file. Tags specify the logical read order of the PDF file and provide hooks for other accessibility elements. This includes alternative text descriptions for graphics.
When the PDF file has been tagged, add alternative text to graphics in the document. Also add short descriptions to any form fields and interactive controls that form part of the document.
Check your PDF file
Make sure that the tagging is correct by checking its read order. Also make sure all necessary alternate text elements are present for graphics and multimedia elements. Check that short description labels are provided for form fields and interactive controls if the document:
- is a form
- features interactive navigation
The Web Content Accessibility Guidelines can be applied to non-HTML documents. For advice refer to chapter 10: non-web documents of EN 301 549 on the Accessible ICT Procurement Toolkit.