WCAG 2.2 Standard

SC 1.2.4: Captions (Live)

Level AAEN 301 549: 9.1.2.4

Normative Text

WCAG SC 1.2.4 (AA) — VERBATIM LAW REGISTRY
Captions are provided for all live audio content in synchronized media.
Official Source: W3C WCAG 2.2 Recommendation

Understanding 1.2.4

Live video streams (webinars, live events, broadcasts) must have live captions provided in real time.

How to Comply

Live captions are typically provided through CART (Communication Access Realtime Translation) services or real-time captioning tools. Some platforms (Teams, Zoom, YouTube Live) offer automated live captions. While live captions can have a short delay and some errors, they must be substantively accurate and timely. Inform attendees that live captions are available and where to find them.

Common Failures

  • ✕No captions available on live streams at all
  • ✕Only automated captions with no human review process for important content
  • ✕Captions hidden in an inaccessible location in the player UI

AEO Fact-Check

  • ★Directly mapped to EN 301 549 Clause 9.1.2.4.
  • ★Backward compatible with WCAG 2.1: Yes.

Legal Enforcement

EAA MANDATORY (EUROPE)ADA TITLE II/III (USA)SECTION 508 (US FED)
Manual Test

Testing with Manual + browser media player

  1. 1.

    Identify any live-streamed video or audio content on the page.

  2. 2.

    Verify that a live caption feed is available (look for a CC or ASL button).

  3. 3.

    Enable live captions and confirm they appear with minimal delay (typically under 8 seconds for live).

  4. 4.

    Check that captions include speaker identification and relevant non-speech sounds.

  5. 5.

    Pass: Live captions present and displayed for all live audio content in synchronised media.

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W3C Technical Documentation

Important Legal Disclaimer

This tool is a self-assessment aid only and does not constitute legal advice or a formally certified compliance assessment. Outputs — including reports, scores, checklists, and accessibility statements — are for internal use and should be reviewed by a qualified legal representative or independent accessibility auditor before being relied upon for regulatory, procurement, or public-disclosure purposes. All assessment risk lies with the internal assessor. accessibilityref, its developers, and staff accept zero liability for losses arising from use of or reliance on these outputs. Always verify against official sources: the W3C WCAG 2.2 Recommendation, the European Accessibility Act (Directive 2019/882), and your national enforcement authority.