Web Content Accessibility Guidelines

What are the Web Content Accessibility Guidelines?

Web Content Accessibility Guidelines (WCAG) are guidelines published by the Web Accessibility Initiative through the World Wide Web Consortium that outlines several recommendations that can be used to make your website universally accessible. The Web Content Accessibility Guidelines 2.0, developed in 2008, highlighted four principles (perceivable, operable, understandable, and robust) to make your website accessible.

Web Content Accessibility Guidelines 2.0 has conformance standards that are requirements for accessibility.

Conformance Levels:

Level A (minimum): This explains the most basic accessibility features but does not achieve broad accessibility
Level AA (mid-range): This addresses the most common issues for users with a disability
Level AAA (highest): This addresses the highest level of web accessibility but is not recommended as a general policy because it is not possible to meet al the criteria

Perceivable

Information on your website must be presentable to users in ways they can perceive. There are some users with vision impairment that will have difficulty accessing your site, which can require them to use assistive technology to help view the content on the website.

Guideline 1.1 - Text Alternatives must be provided for any non-text content.

All images should have an equivalent alternative text
Accessible text alternatives identify multimedia

Guideline 1.2 - Time based media is given text alternatives.

Text descriptions are given to web-based audio and MP3 files
Text or audio descriptions are given for web-based video only
Captions are provided for web-based video (Ex. Youtube Videos)
A web-based video offers a text transcript or audio description
All live multimedia with audio have captions
Video content is given audio descriptions
All media content with audio provide a sign language video
Alternative videos are given audio descriptions
All pre-recorded media with a video receives a descriptive text transcript
All live content with audio receives a descriptive text transcript

Guideline 1.3 - Content must be created that can be presented in multiple ways without losing any information.

Users can access information through assistive technologies and text
The sequence of the content makes sense
The contents instructions aren't only based on sound, shape, size or visual location

Guideline 1.4 - Content must be easy to hear and see.

Color is no used as the sole method expressing content.
The page is readable when the text size is doubled.
Audio of speech is easy to hear with little to no background noise.

Examples:

Visually impaired users need to be able to receive information via sound or touch
Hearing impaired users need to be able to receive information via sight
Users with impaired vision need to be able to receive information with alternative formatting or zoomed to larger sizes
Colorblind users must be able to receive information without the use of color

Operable

User interface components and navigation must be operable. Websites must have keyboard-only navigation and a lack of time limits for its users. This can help the many different ways that some people browse the internet. There are those with some motor difficulties that require their keyboard to navigate a website. This can be implemented by allowing the keyboard to control sliders, activate and operate video players and control windows.

Guideline 2.1 - All functions must be available using a keyboard.

The user can navigate everything on any page using only their keyboard

Guideline 2.2 - there is enough time to read and engage with the content on a webpage

The user can control a pages time limit
The user can refresh and continue what they were doing if a session expires

Guideline 2.3 - Make sure your content does not induce seizures.

There should be no more than three flashes per second

Guideline 2.4 - Make sure users can navigate your website easily

Provide a skip navigation link
Have a descriptive page title
Give a user the opportunity to browse web pages through many different avenues
Ex. Table of contents, sitemap, etc.
There aren’t any links with the same text that go to different places.

Examples:

Functions triggered via mouse or gesture are also available with a keyboard
All users have a sufficient amount of time to read and use the content.
Content does not induce seizures.

Understandable

Information and the operation of user interface must be understandable. This is important because it allows your website to be perceivable and operable. Without the ability to understand the content on your site, there cannot be accessibility. Simple instructions are necessary and an effective way of communicating complex issues. Clear and concise content allows for the user to have a better understanding of complex information.

Guideline 3.1 - Make sure that the content is readable and understandable.

Ambiguous words are defined using a definition list or glossary
The pronunciation of a word is provided following the word or through a link or glossary

Guideline 3.2 - Web pages should be predictable

There should be no changes that confuse or disorient the user
The navigation links have the same order throughout the website

Guideline 3.3 - Helping user avoid fix mistakes

Give the user the ability to identify errors and fix them
Provide instructions to help a user complete a form and submit it

Robust

Your content must be strong enough that it can be interpreted by a wide variety of user agents, particularly assistive technologies.

Guideline 4.1 - Maximize compatibility with current and future user agents, including assistive technologies.