Designing for Assistive Technologies

By Peter Berryman, MFA
Georgia Southern University






When most people use the Web, they read, watch, listen, point and click with a mouse, and type on a keyboard – but not everyone can do all of these things. Fortunately, assistive technologies help learners overcome impairments by providing them with alternative means to perceive, operate, and understand the Web.

Types of Assistive Technologies

  • Screen Readers: Read aloud content published as text to users with visual impairments.

  • Closed Captions (CC) or Transcripts: Video players allow closed captions to be added so that users with hearing impairments can read the dialogue as it is spoken.

  • Screen Magnifiers: Enlarge or zoom into content on the screen.

  • Mouth Sticks: Long sticks clenched between the teeth to type on a keyboard.

  • Speech-to-Text Translators: Convert spoken words to text.

  • Braille Printers: Print digital text to braille.

  • Reading Glasses: Compensate for the effects of presbyopia – loss of near-focusing ability typically by older adults.

Of all the types of assistive technologies, two of them – screen readers and closed captions – require the bulk of our attention when designing content for online courses. The good news is that optimizing documents for screen readers and creating captions (or transcripts) for multimedia is not that difficult!


About Screen Readers

When online information is properly formatted, Screen readers can:

  • decipher and read aloud document structure if headings, lists, and hyperlinks are properly formatted.

  • decipher and read aloud the content and meaning of images, graphs, maps, and diagrams if alternative text descriptions of visual media are encoded (hidden from view) into the document.

  • allow users to navigate document content using keystrokes on a keyboard to jump from heading to heading for each document section.

  • create a list of all hyperlinks out of context of a document so that users can quickly navigate from web page to web page.

Optimizing Document Structure for Screen Readers

When designing documents and files for screen readers, keep in mind they do not “read” what is written on the surface of the document. Instead, screen readers read the underlying code used by software to describe document structure and presentation as well as read aloud text content.

Optimizing Document Structure for Screen Readers
Table 1. Screen readers describe document organization and structure based on a document’s source code.Important! In order for screen readers to describe and read aloud document structure, the source code must include specific notations that are interpreted verbosely and read aloud to students. The good news is that you do not need to know source code to make your document accessible, you only need to know how to use some very conventional and common features built into almost every type of software.


Optimizing Images for Screen Readers

Since screen readers cannot decipher the content and meaning of an image, they look at parts of the underlying code used to place the image by the software for an alternative text description of the image.


Optimizing Images for Screen Readers
Table 2. Alternative text is read aloud by screen readers to describe images to students.Important! To describe the content of images, screen readers look for alternate text descriptions. For the image of Falling Water, the source code contains the description, “Falling Water, Architect, Frank Lloyd Wright”. Less meaningful parts of the source code, such as the source (src), are ignored.

What About Supporting Other Assistive Technologies?

For the most part, other types of assistive technologies -- like screen magnifiers or mouths sticks -- are not as dependent upon how content is created and formatted with the exception of adding closed captions or transcripts for multimedia files. We’ll cover text equivalents for multimedia later in the lesson.