Creating accessible PDF documents

Introduction

Producing accessible PDF documents requires to follow recommendations to make sure they are structured through proper tagging, to make them understandable and useable by everyone (including users with assistive technology).

Below are listed guides aiming at providing necessary information in order to manually create accessible PDF documents based on the most popular softwares, then we will list the mandatory criteria to follow for PDF accessibility.

Guides to create accessible PDF documents

With Microsoft Word

You will find Microsoft Word recommendations as well as the PDF export procedure on our Creating accessible Word documents page.

With Adobe InDesign

You will find Adobe InDesign recommendations (in French) at Créer des documents PDF accessibles avec Adobe Indesign by the AcceDe PDF initiative.

This document was produced by AcceDe PDF phase 1 (2011), driven by Atalan together with 9 enterprises: Spie, Air Liquide, Société Générale, BNP Paribas, Areva, LVMH, Capgemini, Thales et SNCF, who relied on a review team made up of numerous professionals and organisations involved in digital accessibility.

With Adobe Acrobat Pro

You will find Adobe Acrobat Pro recommendations at Making PDF documents accessible with Adobe Acrobat Pro by the AcceDe PDF initiative.

This document was produced by AcceDe PDF phase 2 (2015), driven by Atalan together with Orange and 9 other enterprises: La Poste, Siemens, Spie, Thales, Atos, BNP Paribas, Devoteam, Manpower and EDF, who relied on a review team made up of numerous professionals and organisations involved in digital accessibility.

Testing the accessibility of a PDF document

Install PDF Accessibility Checker (PAC).

This tool can, among other things, run automatic tests on a PDF document and check for accessibility issues.

Screenshot of automatic tests in PAC
Screenshot of the tool

Mandatory criteria

The following are the main criteria for a PDF document to be accessible, regardless of the method used to create it. Mandatory criteria will be useful for people creating PDF documents even when they don’t rely on publication software (Microsoft Word, Adobe InDesign, Adobe Acrobat Pro), e.g. developers whose applications generate PDF documents.

Document structure

Le document doit contenir a minima un titre de document et une langue par défaut (les changements de langues seront indiqués dans le document).

The document must at the very least include a document title and a default language (language changes must be indicated in the document).

See PDF16, PDF17, PDF18.

The document is structured with titles, through the proper use of title “tags”. Moreover, long documents must include bookmarks to make navigation easier.

See PDF2, PDF9.

The use of headers and footers must help the user locating themselves in the document.

See PDF14.

Keyboard navigation and reading order

The reading order conveyed by an assistive tool, as well as keyboard navigation (through tabbing) must reflect the document’s structure. There must be no keyboard trap (keybaord navigation must be possible in the whole document without any blocking point).

See PDF3, G21.

Images

Images featuring information must have an appropriate alternative. Scanned documents must be covnerted to text through optical character recognition (OCR). Decorational images must be hidden.

See PDF1, PDF4, PDF7.

Tables

A data table must be structured by a table “tag” containing at least one line. Table headers must be used appropriately. All lines must contain the same number of cells. Merged cells must clearly indicate if the merge was vertical or horizontal (rowSpan or colSpan attribute).

SeePDF6.

Link texts must be explicit, or the links must provide an accessible alternative.

See PDF11, PDF13.

Lists

Lists must use the appropriate “tags”: list tag L, list item tag LI, list item label tag Lbl (for instance the item number, or the Lbody content tag of the list item).

See PDF21, section 14.8.4.3.3 of the PDF specification.

Forms

Form fields must have a name, a role, a value, and a state (if needed). Visually, labels must be correctly positioned towards the field. Mandatory fields and expected formats must be indicated. Fields must be accessible and keyboard-modifiable. Forms that can be submitted must provide a submit button.

See PDF5, PDF10, PDF12, PDF15, PDF22.

Colours

Colours must not be the only means to convey information.

Contrast between the colour of text and of its background must be sufficient:

  • 4.5:1 for normal-size text;
  • 3:1 for bigger text.