Accessibility Rules and Guidelines

Who made and maintains accessibility rules?

The World Wide Web Consortium (W3C) is an international community of staff, public and member organizations collaborate to develop web standards to support their mission of leading the Web to its full potential.

W3C creates the Web Content Accessibility Guidelines (WCAG), which is the result of years of collaborations with users with disabilities and their allies to make the web accessible to all.

What are the main guidelines, and where are the rules published?

There are three levels of standards, where the level prior needs to be met before the next level of accessibility changes can make a lasting impact. The levels all revolve around four core principles. The WCAG 2.1 standards have a partnered Understanding Techniques for WCAG Success Criteria manual that provides the reasoning behind the criterion, as well as examples of good and bad code to meet it.

The Three Levels of Standards

  • Level A: Required to meet minimum WCAG standards (e.g. every site has a page title).
  • Level AA: Highly recommended for comprehensive inclusiveness (e.g. text can be resized up to 200%).
    • Importantly, AA is the level of standard that Tufts requires for its websites.
  • Level AAA: Stretch goals for complete and total inclusiveness (e.g. low or no background audio).

Here is a full reference list of the standards on the W3 website. If you’d like, you can head straight there, filter in the left sidebar for A and AA, and search for the elements you’re working in.

The WCAG Principles

The techniques of WCAG evolve over time, but the core principles never change. Copying directly from the official WCAG website, the guidelines require that all content we offer is:

  1. Perceivable
    • Provide text alternatives for non-text content.
      • For example, instead of scanning and uploading a PDF of a textbook, providing the actual text that a screen reader can navigate.
    • Provide captions and other alternatives for multimedia.
      • For example, provide captions for any audio for the hearing impaired.
    • Create content that can be presented in different ways , including by assistive technologies, without losing meaning.
      • For example, a chart in a MS Excel spreadsheet can also be described or narrated.
    • Make it easier for users to see and hear content .
      • For example, small gray text on a white background is quite hard to see for anyone, especially those with visual impairments.
  2. Operable
    • Make all functionality available from a keyboard .
      • For example, a user without a mouse should still be able to get through your content.
    • Give users enough time to read and use content.
      • For example, don’t have PowerPoint slides that automatically advance after a few minutes.
    • Do not use content that causes seizures or physical reactions.
      • For example, don’t have PowerPoint transitions or animations that involve flashing lights or blinking text.
    • Help users navigate and find content .
      • For example, built-in headings in websites and MS Word help keyboard users jump to the content they’re interested in.
    • Make it easier to use inputs other than keyboard .
      • For example, if on a touch screen, make buttons large enough for someone with poor motor control to hit.
  3. Understandable
    • Make text readable and understandable.
      • For example, explicitly state the language content is in and make it easy to switch languages (if possible).
    • Make content appear and operate in predictable ways.
      • For example, on a website, don’t change where the nav menu is located on each page.
    • Help users avoid and correct mistakes.
      • For example, if you ask for a phone number input, check the input and provide feedback as text.
  4. Robust
    • Maximize compatibility with current and future user tools.
      • For example, on a website, use HTML5 wherever possible.