Online courses need to meet specific criteria in order to be ADA-compliant. The Web Content Accessibility Guidelines (WCAG) 2.1 is international standards and best practices for web accessibility. It has 78 Success Criteria broken into 3 levels (A – minimum level of conformance, AA – recommended, AAA – best and most accessible). WCAG 2.1 A/AA is generally accepted as the appropriate standard for measuring web accessibility.
WCAG 2.0 was published in December 2008 and 2.1 was updated in June 2018 with additional success criteria to improve mobile accessibility for people with low vision and cognitive and learning disabilities. WCAG 2.2 is under development and will probably be published in 2020.
Web Content Accessibility Guidelines Structure
Success Criteria (78)
- Level A (30)
- Level AA (20)
- Level AAA (26)
First, it is important to acknowledge four web content accessibility principles, Perceivable, Operable, Understandable, and Robust (POUR) based on WCAG 2.1:
Perceivable: Information and user interface components must be presentable to users in ways they can perceive. This means that users must be able to perceive the information being presented (it cannot be invisible to all of their senses). Some of the most common guidelines are:
- Provide alternative text so that it can be changed into other forms people need, such as large print, braille, speech, symbols or simpler language.
- Create content that can be presented in different ways without losing information or structure.
- Make it easier for users to see and hear content including separating foreground from the background (e.g. color contrast).
Operable: User interface components and navigation must be operable. This means that users must be able to operate the interface (the interface cannot require interaction that a user cannot perform). Some of the most common guidelines are:
- Make content and navigation functional using both keyboard and mouse.
- Provide ways to help students navigate, find content, and determine where they are.
Understandable: Information and the operation of user interface must be understandable. This means that users must be able to understand the information as well as the operation of the user interface (the content or operation cannot be beyond their understanding). Some of the most common guidelines are:
- Make text content readable and understandable.
- Help users avoid or correct mistakes.
Robust: Content must be robust enough that it can be interpreted reliably by a wide variety of user agents, including assistive technologies. This means that users must be able to access the content as technologies advance (as technologies and user agents evolve, the content should remain accessible). Some of the most common guidelines are:
- Maximize compatibility with current or future user agents, including assistive technologies.
Guideline 1.4 – Distinguishable: Make it easier for a user to see and hear content including separating foreground from background.
1.4.1 Use of Color
Level A (the most attainable): Color is not used as the only visual means of conveying information, indicating an action, prompting a response, or distinguishing a visual element.
1.4.3 Contrast (Minimum)
Level AA (most often referenced in lawsuits and legal recommendations): The visual presentation of text and images of text has a contrast ratio of at least 4.5:1, except for large text (3:1), incidental (decorative ones), or logotypes (part of logo or brand name).
1.4.6 Contrast (Enhanced)
Level AAA (often the most accessible, but the hardest to achieve): The visual presentation of text and images of text has a contrast ratio of at least 7:1, except for large text (4.5:1), incidental (decorative ones), or logotypes (part of logo or brand name).
1.4.12 Non-text Contrast
Level AA: The visual presentation of user interface components and graphical objects have a contrast ratio of at least 3:1 against adjacent color(s).
Assistive Technology Examples
There is a wide variety of assistive technology supporting people with disabilities interacting with digital interfaces.
- Screen Readers
- Zoom/Screen Magnification
- Speech Input
- Voice Control/ Dictation
- Braille Displays
- Closed Captioning
- Audio Description
- Keyboard Only
- Input Devices and Switches
Screen reader (for example, JAWS and voiceover), is a software to synthesize text from and output via text-to-speech or a Braille display. JAWS (Windows) is free for the U of I faculty, staff, and students to use.
If you have any questions or suggestions on this topic, please contact Jinhee Choo (firstname.lastname@example.org).