PDF publishing standards

Shelter's preferred format for publishing digital content is web content pages because they are generally easier for people to access and use with assistive technologies, such as screen readers. They should be your first choice whenever possible. We are committed to meeting WCAG’s AA accessibility standards and designing for digital inclusion. Shelter website accessibility statement. 

PDFs (Portable Document Format) should only be published where there is a clear business need, such as providing a printable document for formal reports and resources in a fixed layout. 

Where PDFs are used, they must be accessible to all users and meet the requirements set out in this standard. This applies to:  

• all new PDF documents published on Shelter websites 

• existing PDF documents that are significantly updated or republished 

• PDFs created internally or by third-party suppliers on behalf of Shelter 

Roles and responsibilities 

Teams requesting or arranging content creation are responsible for ensuring accessibility requirements are considered from the outset of a project and are clearly communicated and defined to any internal teams, suppliers, agencies, or third-party partners.  

Teams should seek advice where there is uncertainty about the content or document format selection. Decisions to use PDF should be informed by user needs and accessibility considerations rather than organisational preference or existing processes.

When a PDF is produced, the producer must demonstrate they have met these standard requirements. 

Standard requirements 

Consider the most accessible format first 

Before creating or publishing a PDF, content owners must determine whether the information can be provided in a more accessible format. Where content is primarily intended for online reading, it should be published as web content rather than as a PDF.  

If a downloadable version is needed, consider whether an editable document format, such as a Word document or Open Document Text (ODT), would better meet user needs.  

A PDF should only be used where: 

• publishing the content as web content is not practical or proportionate, and 

• there is a genuine requirement for a downloadable document in a fixed layout 

Note - Word documents must be created and checked to the same standards expected of PDFs. 

Accessible source documents 

PDF accessibility begins with the source document. 

Documents must be created using accessible practices in applications such as Microsoft Word or Adobe InDesign before exporting to PDF. 

Accessibility should be built into the document from the start. Fixing accessibility issues after a PDF has been published is often more complex, time-consuming, and costly. 

Guide to making a Microsoft Office document accessible  

Guide to making an InDesign document accessible. 

Basics | accessible-pdf.info 

Document structure 

A well-structured PDF helps screen readers, keyboard users, and other assistive technologies understand and navigate the content. 

PDF documents must: 

• include accurate metadata (document title and language) 

• use a meaningful heading hierarchy starting with heading 1 for the title, heading 2 for section headings, and heading 3 for subheadings within sections 

• maintain a logical reading order so content is read in the correct sequence 

• include tagged content (structural information that helps screen readers understand headings, paragraphs, lists, and tables) 

• support keyboard navigation with bookmarks, a table of contents, and descriptive hyperlinks 

• not rely on colour alone to convey meaning – use other indicators such as text labels or underlines (for links) 

Text and readability 

PDF documents must: 

• not use bold to infer hierarchy 

• not skip heading levels  

• contain searchable text 

• support reflow, meaning users can zoom in up to 400% and still read and use the document without needing to scroll horizontally or losing information 

• use sufficient colour contrast 

Images and non-text content 

Users who cannot see images, charts, and diagrams need a text alternative that conveys the same information.  

Requirements include: 

• meaningful alternative text for informative images that communicates the purpose of the image, not just describes what it looks like. Eg. alt="Line graph illustrating energy bills doubled over four years” 

• decorative images marked as decorative 

Tables 

Tables must only be used to present data and not for page layout.  

When tables are used: 

• table headers must be identified 

• table structure must be logical 

• complex tables should be avoided where possible 

• users must be able to tell which column and row headings relate to each piece of data 

Links and interactive content 

Links must: 

• use meaningful link text; instead of ‘here’ or ‘more’, use ‘read our guide on link text’ 

• clearly describe the destination and what you will find 

• be fully keyboard accessible 

• forms and other interactive elements must include appropriate labels, instructions, and keyboard navigation 

Document metadata 

All PDFs must include a meaningful document title. The document title should accurately describe the content and purpose of the document.  

Accessibility testing 

Use the source file's accessibility checker before exporting your PDF. 

Before publication, all PDFs must undergo accessibility testing. This can be achieved with an automated accessibility checker - Adobe Accessibility Checker, PAC (PDF Accessibility Checker), or equivalent tools. 

As a minimum: 

• all identified errors must be resolved 

• any items flagged for manual review must be checked by a person, as automated tools cannot identify every accessibility issue 

• reading order must be verified 

• links must be tested 

Mandatory pre-publication checklist 

Before a PDF is published on a Shelter or Shelter Scotland website, the publisher must confirm that: 

* Exceptions: as we move to this standard, any request to publish a PDF that does not meet this standard must be reviewed and agreed on a case-by-case basis by a Digital Product Manager.  

It is easier to create a simple HTML page than to fix a PDF that is inaccessible. However, here is a video guide if you need to remediate PDFs for accessibility. 

Questions and advice 

Need advice on whether a PDF is the right format?  

In England you can contact contentanduserexperience@shelter.org.uk 

In Scotland you can contact ContentScotland@shelter.org.uk