Accessibility in documents

To ensure that PDF documents are accessible, the source documents should already be designed accordingly. Some key tips and information:

• Always work with format templates so that headings, bulleted lists, links etc. are recognised as such by screen readers. This means that you should only format in Microsoft Word with the intended format templates (standard, heading 1, 2, 3, lists, etc.). Insert tables using "Insert table". Always use the master templates in Microsoft PowerPoint when inserting new slides. Check the reading order on the slides, e.g. by using the tab key to move through the slide. The reading order can be changed via "Arrange - Selection area".
• Images, graphics and other non-text elements require alternative texts. Alternative texts are short descriptions of the images. They are entered via the context menu. For complex graphics, it may be useful to publish the longer description directly in the document. See also: Four short rules for alternative texts from the DBSV.
• Ensure good contrasts between foreground and background (text and background). Light colours on a white background are difficult to see. For light-coloured fonts on a dark background, a stronger font weight (semi-bold/bold) should be used and the font size increased by approx. 10 percent.  The key measure is the contrast ratio, which should be 4.5:1 for text and 3:1 for headlines. Contrast calculators such as the Colour Contrast Analyser or from leserlich.info are helpful.
• Avoid busy backgrounds or colour gradients behind text.
• Use easily readable fonts without serifs.
• Colour vision defects are a common visual impairment. Colour should therefore not be used as the only distinguishing feature (e.g. red=wrong, green=right). The information should also be available in writing or shape. You can use the Adobe colour wheel to test colour combinations; it simulates common colour mismatches.
• Use the accessibility check of Word and PowerPoint to check your finished document. The automatic check cannot detect all errors, but it can detect many.
• Create the PDF using "Save as" and not "Print PDF".

For longer or more complex documents with columns or inserted images, the document may still need to be edited in Acrobat Pro in order to create the correct reading order for screen readers. Therefore, as a general rule, please provide students who work with screen readers documents as Word or PowerPoint files.