Designing for Deaf Users: Audio Accessibility

Understanding Deaf and Hard-of-Hearing Users

Approximately 48 million people in the United States have hearing loss, with millions more worldwide. Audio accessibility—providing alternatives to audio content—is essential for deaf and hard-of-hearing users. Captions, transcripts, sign language interpretation, and visual alternatives ensure audio content is accessible to all users.

The deaf and hard-of-hearing community encompasses diverse experiences. Some users are completely deaf from birth or early childhood; others lost hearing later in life. Some use spoken language; others use sign language as primary communication. Hearing aid users might have better hearing in quiet environments but struggle in noisy settings.

For website design, the key principle is this: audio content must have accessible alternatives. If your site includes videos, podcasts, webinars, or other audio content, that content must be accessible to users who cannot hear it.

Unlike visual accessibility (which affects 1 in 4 adults at some point), hearing loss is often invisible. Users might not disclose hearing loss, making it easy for organizations to overlook audio accessibility needs.

Core Audio Accessibility Elements

1. Captions (Closed Captions)

Closed captions (CC) transcribe dialogue and sound effects from video content. They include not just spoken words but also [ambient traffic], [door slams], [music playing]—giving deaf viewers complete audio understanding.

Good captions include:

• All dialogue and spoken content
• Sound effects in brackets: [phone ringing], [laughter]
• Music descriptions: [upbeat jazz music]
• Speaker identification: [JOHN]: "Let's begin"
• Accurate timing synchronized with video

2. Audio Descriptions

Audio descriptions provide narrated descriptions of visual content. For videos, audio descriptions are spoken during natural pauses in dialogue, describing on-screen actions users cannot hear.

Example: During a instructional video, audio description might say: "The technician carefully removes the circuit board from the device" during the scene showing this action.

Audio descriptions allow blind users to understand visual content; they also benefit low-vision users and users in environments where they cannot watch closely.

3. Transcripts

Transcripts are written text versions of audio content. For podcasts, webinars, or recorded videos, provide full transcripts. Transcripts provide:

• Text access to audio-only content (podcasts)
• Searchable content (users can find specific topics)
• Better SEO (search engines index text, not audio)
• Multiple accessibility benefit (screen readers can read transcripts)

4. Sign Language Interpretation

For important video content, consider sign language interpretation. Many deaf users prefer sign language to captions. Sign language interpreters appear in a window during videos, interpreting content.

While more resource-intensive than captions, sign language interpretation benefits deaf users who are Deaf (capital D—culturally deaf, using sign language as primary communication).

5. Visual Indicators for Sound

Some content relies on audio cues users must hear: error notifications, confirmation sounds, or alerts. For such content, provide visual equivalents: error messages appear on screen, confirmation icons flash, or alerts are visually highlighted.

Designing Video for Accessibility

Video Player Accessibility

Video players themselves must be accessible:

• Caption toggle: Clear, obvious button to turn captions on/off
• Caption visibility: Captions must be readable with 7:1 contrast, large enough to read, and not blocking important video content
• Transcript link: Direct link to transcript near player
• Keyboard controls: Play/pause, volume, closed captions accessible via keyboard
• Focus management: Keyboard users can access all controls

Caption Quality Standards

Poor captions are sometimes worse than no captions. Guidelines for caption quality:

• Accuracy: Captions must accurately represent spoken content
• Completeness: All dialogue and relevant sounds included
• Timing: Captions appear and disappear synchronized with audio
• Speaker identification: Clear who is speaking, especially in multi-speaker content
• Sound descriptions: Important sound effects and music included
• Readability: Text large enough, readable fonts, sufficient contrast

Where to Place Captions

Captions appear at video bottom by default, but position should be adjustable. Some caption formats (open captions burned into video) cannot be repositioned; closed captions (separate, toggleable) should be adjustable in position.

Transcript Formatting

Transcripts should:

• Be clearly labeled and easily accessible near video player
• Include speaker identification for clarity in multi-speaker content
• Include timestamps for reference
• Describe important sound effects and music
• Include text formatting for readability (paragraphs, speakers on new lines)

Designing for Audio-Only Content (Podcasts)

Transcript Requirement

Podcasts and audio-only content must have transcripts. Provide complete transcripts of all podcast episodes, clearly linked from episode pages.

Transcript Quality

Podcast transcripts should:

• Include all spoken content accurately
• Identify speakers clearly
• Include timestamps every few minutes
• Include descriptions of significant sound effects or music
• Be searchable (PDF transcripts are less searchable than HTML)

Transcript Placement

Place transcripts on the same page as audio player. Users should not need to search for transcripts; they should be obvious.

Sponsorships and Advertisements

Even sponsored segments and advertisements in podcasts should be transcribed. Exclude only truly incidental background audio.

Live Events and Webinars

Real-Time Captions

For live streams and webinars, real-time CART (Communication Access Realtime Translation) captioning provides live captions. Professional CART services employ trained captioners who listen and type captions in real-time, typically with 99% accuracy.

Planning for Live Audio

When hosting webinars or live events:

• Budget for professional CART captioning
• Provide platform for captions display
• Allow speakers to review captions (some services provide speaker console)
• Record webinars for later captioning and archiving

Recorded Webinars

After webinars conclude, captions should be added to recordings before publishing. This requires either recording the CART caption feed or adding captions in post-production.

Audio Descriptions in Detail

When Audio Descriptions Are Needed

Audio descriptions are most important for:

• Instructional videos showing procedures or techniques
• Training videos with visual demonstrations
• Narrative videos where visual storytelling is central
• Product demonstrations

Audio descriptions are less critical for videos that are primarily talking-head (someone speaking to camera) where dialogue covers all necessary information.

Audio Description Guidelines

Good audio descriptions:

• Are concise but complete
• Fit naturally into content pauses
• Use clear, simple language
• Describe important visual details, not obvious elements
• Are objective, not subjective or interpretive

Creating Audio Descriptions

Professional audio description services employ trained describers who watch video and write descriptions, then narrators record those descriptions, which are edited into video during natural pauses.

For organizations with limited budgets, AI-assisted tools are emerging that automatically identify key visual moments and suggest descriptions, which professionals then refine.

Testing Audio Accessibility

Caption Quality Review

Watch videos with captions on, audio off. Verify:

• All dialogue is captured accurately
• Sound effects are described
• Captions are visible and readable
• Timing is synchronized properly
• Speaker identification is clear

Transcript Verification

Read transcripts independently. Verify:

• Transcripts match spoken content
• Sound descriptions are included where relevant
• Transcripts are easy to read and navigate
• Timestamps help navigation

User Testing with Deaf Users

If possible, involve deaf users in testing. Deaf users identify caption quality issues that hearing testers miss and provide invaluable feedback on accessibility effectiveness.

Common Mistakes to Avoid

• Auto-generated captions only: Automated captions are often inaccurate and miss sound effects. They're better than no captions but should be reviewed and corrected.
• No transcript: Videos may have captions but no transcript for easy reference or searching.
• Burned-in captions: Open captions burned into video cannot be turned off or repositioned. Use closed captions.
• Missing speaker identification: Multi-speaker content without clear speaker IDs is confusing.
• No sound effect descriptions: Captions showing only dialogue miss important audio context.
• Unreadable caption appearance: Small captions, low contrast, or covering important video content reduce accessibility.
• No audio description consideration: Assuming captions are sufficient when video requires visual descriptions.

Content Creator Responsibilities

Organizations should establish accessibility requirements for content creators:

• All videos must have captions before publishing
• Captions must be reviewed for accuracy, not just auto-generated
• Transcripts must be provided for audio-only content
• Instructional videos should include audio descriptions
• Caption and transcript files should be organized and linked properly

Key Takeaways

• Approximately 48 million people in the US have hearing loss; audio accessibility is essential.
• Closed captions should include all dialogue, sound effect descriptions, and speaker identification.
• Transcripts must be provided for all audio-only content and videos.
• Audio descriptions help blind users and benefit all users in certain contexts.
• Video players must have accessible caption controls and support keyboard navigation.
• Live events require real-time CART captioning; recorded content requires captions added post-production.
• Auto-generated captions should be reviewed and corrected by humans before publishing.
• Involve deaf users in testing audio accessibility whenever possible.

Resources

• WCAG 2.1 Guidelines
• Video Captions (WebAIM)
• Described and Captioned Media Program
• National Captioning Institute
• The A11y Project