Skip to Page Content
Guidelines: Accessible
 Distance Education

Guidelines: Accessible Adobe PDF Files



Categories: MUST Should May

The "Must Items" are critical to basic access for people with disabilities.

 
  1. A version no older than Acrobat 5.0 should be used to create PDF documents.Acrobat 5.0 has new features that are critical for the accessibility of PDF documents. Among the most important of these features are tags, which provide an underlying language that an assistive device can use in order to read information in the file. Acrobat 5.0 also has an accessibility checker, which was not present in previous versions of the product

  2. Tag all documents for easier reading by screen readers and other assistive technologies.Tagging documents using Acrobat's Tag Palette allows for more accessibility features to be implemented in the document, such as text equivalents. The tags create an underlying "language" that describes to the assistive technologies what needs to be said and how to say it.

  3. Create alternative text for all images.Because assistive devices cannot yet describe images, it is necessary to create some "underlying description" of the image that the assistive technologies recognize and read, but that is not visible to those who have no visual impairments.

  4. Make sure security is formatted correctly to allow for assistive devices.If text is prohibited from being copied in Acrobat 4.0, or if in Acrobat 5.0 accessibility is prohibited, the entire document becomes inaccessible to assistive devices. This is why it is necessary to make sure it is important to enable accessibility settings while retaining security.

  5. Make sure text and foreground images contrast sufficiently with the background.Images, text, and background that are the similar colors tend to blur and "run together" for those users who have visual impairments but do not use assistive devices. This is why it is necessary to avoid using similar colors for text and background, and images and background.

  6. Provide a natural language for the text.Providing a primary language for the document tells assistive technology how to interpret the content of the file. This becomes extremely important if the document is published on theInternet, and is viewed by people all over the world.

  7. Provide a text equivalent for any multimedia that includes speech, or music with lyrics.Users who suffer from hearing impairments would find auditory information difficult, if not impossible, to understand. That is why it is necessary to include a transcript that describes all audio that is present in the document and is relevant to the user. The transcript should be located in the vicinity of the auditory information, or a link should exist in the vicinity of the auditory information that would connect to a transcript.

  8. All important or relevant parts of the document should be part of the document structure.If a part of the document is outside of the document structure (not listed as a tag in the Tags Palette), it will not be read by an assistive device, such as a screen reader. If importing from a Microsoft Word application, headers and footers, as well as page numbers, are outside the document structure, and are thus not read by assistive technologies. It is thus necessary to add tags for all of those respective elements

  9. Color should not be the only method of conveying information.Any information displayed through color will cause problems for those that have visual impairments such as color blindness. Provide a substitution, preferably a text substitution, that describes precisely the information that needs to be conveyed to the user.


Top of Page