OU Libraries Guidelines for Accessible PDF creation
Compiled from “Making PDF files accessible: guidelines for the DTP creation phase” by Atalan on AcceDe (www.accede.info/en/manuals)
Text and general structure
Avoid content which straddles two pages
- Make the object fit on a single page
- Use larger page size
- This rule does not concern paragraphs which begin on one page and end on another. These elements can be used without any problem.
Do not delete space characters between words for visual effect or forced line break
- Use fine spaces or kerning with a negative value
- With forced line break between two words, keep the space at the end of the first word.
Keep accents on capital letters
- All accented characters should be accented even when they appear as capitals.
Do not manually hyphenate a word at the end of a line
- Use DTP software’s hyphenation function.
Do not use superimposed text for shadow effects
- Use DPT shadow effects instead
Explain abbreviations, acronyms, and initials
- Show expanded form at the first instance of the abbreviation or in a footnote or glossary entry.
Pictures and graphics
Do not convey information just with colors
- Combine colors with unique shapes.
Do not insert text which conveys information as images
- Decorative items ok.
- No images made from text present in the document, esp. legends in graphics.
Typefaces
Use typefaces which enable the extraction of characters in text format.
- Adobe recommends OpenType typefaces.
- A typeface must map to Unicode characters
- Symptom of inaccessible typeface would be the presence of characters which fail to map and appear as ???? or ☐☐☐☐
Data tables
Create data tables with the DTP software’s table functionality.
- Tagging a table containing data takes a long time in Adobe Acrobat Pro. When the tables are created with the corresponding functionality in the DTP software, a large part of the tagging can subsequently be automated.
Always enter a character in the empty cells of a table
- Character may be visible or hidden (a character with the same color as the background color
- Speech synthesizers cannot detect empty cells and do not warn the reader that the cell is empty. Consequently, the rendering of the cells that follow an empty cell will by unsynchronized in a speech synthesizer.
- The presence of a character in an empty cell will make it possible to provide the empty cell with an alternative and to maintain the cell sequence.