The Web Content Accessibility Guidelines (WCAG) contains several success criteria regarding audio. One of the most important is WCAG Success Criterion (SC) 1.4.2, “Audio Control:”
If any audio on a Web page plays automatically for more than 3 seconds, either a mechanism is available to pause or stop the audio, or a mechanism is available to control audio volume independently from the overall system volume level.
This is a Level A criterion, which means that it’s an essential consideration for accessibility (read more about WCAG conformance levels). Here’s why this requirement is important — along with a few quick tips for incorporating audio and multimedia into your content.
Why Audio Controls Are Important for Users with Disabilities
Every computer, mobile phone, and tablet has volume controls. Why can’t people simply use those controls to mute website audio?
They can — but if someone needs audio output to use their device, turning off all sound can cause problems. Many people with vision disabilities use screen readers (software that converts text to audio). For those users, turning off the sound isn’t practical; they need to listen to their screen reader’s output to navigate the internet.
Likewise, people with hearing disabilities may browse with their sound turned up. That’s helpful when websites have important audio, but when audio isn’t especially important — as is usually the case with autoplay media — they may feel frustrated.
Related: Why Screen Readers Are Essential for Website Accessibility
Meeting WCAG’s Requirements for Audio Controls
For web designers, the safest approach is to avoid autoplay entirely (we’ve written in detail about why autoplay is an accessibility no-no). However, if you must play audio automatically, make sure you’re following WCAG’s best practices.
1. Make sure your audio controls operate predictably
You have several options for meeting WCAG SC 1.4.2. You must provide one of the following:
- A mechanism to pause audio playback, or;
- A mechanism to control the audio volume.
Ideally, you’ll provide both of those controls. However, for the sake of accessibility, it’s a good idea to go further by making sure that the controls are predictable — the user should be able to intuitively control them without encountering surprises.
Some quick tips for making controls predictable:
- Make sure that the controls are immediately accessible. If audio plays automatically, the controls should be at the top of the page.
- Check that the controls can be operated with a keyboard alone (no mouse).
- Make sure the user can control volume and playback with conventional keyboard commands. When the keyboard focus is on the controls, the spacebar should stop playback. On volume controls, the arrow keys should control volume.
If your media uses unconventional controls (for example, the Enter key), provide instructions for operating them — but standard controls are more intuitive, so don’t defy the user’s expectations unless you’ve got an extremely good reason to do so.
Related: Why Consistency is Important to Accessible Design
2. Don’t play background audio
In the early days of the internet, background music was everywhere — usually, delivered via a low-quality MIDI file. Thankfully, we’ve moved on: Most web designers understand that unnecessary audio is distracting and annoying.
Nevertheless, some websites still play music or ambient sound. If the audio contains speech, this may violate WCAG 2.1 SC 1.4.7, “Low or No Background Audio,” a Level AAA criterion that requires background sounds to be at least 20 decibels lower than foreground speech content.
Most websites don’t aim for WCAG Level AAA conformance, but this is an easy requirement to meet: Don’t play background audio. It rarely improves the user’s experience.
Related: How Background Noise Affects Accessibility
3. When in doubt, avoid using autoplay
We can’t stress this enough: People hate autoplay. While there are limited situations in which autoplay makes sense, it’s usually unnecessary — and in most cases, a simpler presentation actually improves audience engagement.
If you’re looking for ways to create accessible media content, we’re here to help. Contact the Bureau of Internet Accessibility to connect with a subject media expert. For more guidance, download our free eBook, Developing the Accessibility Mindset.