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Jun 25, 2026

Digital accessibility coverage report

How much of your published collection is reachable by visitors who rely on alternative text, captions, transcripts, or a language other than the catalogue's primary one - and where the gaps are.

What this report is (and is not)

The admin report at Admin → Digital accessibility (/admin/accessibility) is a heuristic coverage report over the accessibility-relevant metadata Heratio actually stores. It tells you what proportion of published content carries each accessibility signal, and recommends how to close each gap.

It is not a WCAG conformance audit. A full conformance audit also requires reviewing the running interface itself - keyboard operability, colour contrast, focus order, and so on - which a metadata report cannot measure. The report cites WCAG 2.1 AA success criteria as an international reference grid only.

The report is read-only. It never changes a record, never runs a database migration, and makes no AI calls. It counts only published content.

The areas it measures

Each area shows a coverage level (None yet, Low, Partial, Good, Strong), the "with vs total" big numbers, a CSS coverage bar, the evidence behind the figure, and a recommendation.

  • Image alternative text (WCAG 1.1.1) - published image surrogates that carry a text alternative. A published image counts if either a curator has authored a genuine entry in the dedicated alt-text store (image_alt_text - the real WCAG 1.1.1 signal), or, as a fallback, it carries an embedded IPTC/XMP caption in digital_object_metadata.description. Author genuine alternative text from the Image alt-text curation worklist (/admin/alt-text). Where neither source is available the area reads Not measured.
  • Captions and subtitles (WCAG 1.2.2) - published audio/video surrogates with at least one active caption or subtitle track.
  • Transcripts (WCAG 1.2.3 / 1.2.5) - published audio/video surrogates with a text transcript (a recognised media alternative).
  • 3D model alternative text (WCAG 1.1.1) - published 3D models that carry alternative text. This is a direct measure: 3D models have a dedicated alt_text field.
  • Multilingual access (WCAG 3.1.1 / 3.1.2) - published records readable in more than one language (a real title in two or more cultures).

How the overall level is set

Overall coverage is the lowest level across the measured areas - the collection is only as reachable as its weakest area. Areas with no applicable content (for example, no published audio-visual material at all), or with no place in the schema to record the signal, are shown as Not measured and are honestly excluded from the overall score rather than counted as a failure.

Honest absence

Where Heratio cannot evidence a signal, the report says so. A missing column or table yields a Not measured area with a specific recommendation - it never invents coverage. For image alternative text, curated entries authored in the Image alt-text curation worklist (/admin/alt-text) are counted directly as the genuine WCAG 1.1.1 signal; the embedded IPTC/XMP caption is only used as a fallback where no curated alternative text exists.

Where to find it

Admin → Digital accessibility (/admin/accessibility). It sits alongside the Metadata completeness (/admin/data-quality) and Preservation maturity (/admin/preservation-maturity) reports, and links across to them.