Balisage Paper: Accessibility Metadata Statements

Discoverable documents

Discoverable documents require discovery metadata, including these fields from Schema.org:

Accessible documents

Publications claiming conformance with accessibility standards must include discovery metadata and these additional fields:

Optimized documents

Optimized publications, designed to be accessible to some users but not to others, must include discovery metadata and these additional fields:

Example 1: Graphic novel

This graphic novel does not have any accessibility features built in. As a result, it can only be used by readers who can read the text and look at the visual elements. Note that accessModeSufficient has only one entry.

<script type="application/ld+json">
{
"@context": "http://schema.org/",
"@type": "Book",
"name": "Some graphic novel",
"accessMode": ["textual", "visual"],
"accessModeSufficient": [
{
"@type": "ItemList",
"itemListElement": ["textual", "visual"],
"description": "Text and images"
}
],
"accessibilitySummary": "Visual elements are not described."
}
</script>

Example 2: Video

This video has captions (a visual presentation of the dialog and sound effects) and audio description (an audio track describing important visual features). It can be used in three different ways, for example by a person without disabilities who will listen to the soundtrack and watch the visuals, by a person who is Deaf or hard-of-hearing, who will look at the visuals and read the captions, and by a person who is blind or visually impaired, who will listen to the soundtrack and the audio description. The three entries in accessModeSufficient describe these use cases.

<script type="application/ld+json">
{
"@context": "http://schema.org/",
"@type": "Movie",
"accessMode": ["auditory", "visual"],
"accessibilityFeature": ["audioDescription", "captions"],
"accessModeSufficient": [ 
{
"@type": "ItemList",
"itemListElement": ["auditory", "visual"],
"description": "Watch and listen"
},
{
"@type": "ItemList",
"itemListElement": ["textual", "visual"],
"description": "Watch with closed captioning"
},
{
"@type": "ItemList",
"itemListElement": ["audio"],
"description": "Listen with audio description"
}
],
"accessibilitySummary": "Captions provided in English; short scenes in French have English subtitles instead."
}
</script>

Example 3: Journal article

This exemplary journal article includes descriptions of all images included in the article.

<script type="application/ld+json">
{
"@context": "http://schema.org/",
"@type": "Article",
"name": "Journal article",
"accessMode": ["textual", "visual"],
"accessibilityFeature": ["alternativeText"],
"accessModeSufficient": [
{
"@type": "ItemList",
"itemListElement": ["textual", "visual"],
"description": "Text and images"
},
{
"@type": "ItemList",
"itemListElement": ["textual"]
"description": "Text and images"
}
],
"accessibilitySummary": "All diagrams, charts, and other visual elements are described."
}
</script>

Example 4: illustrated novel

Note in this example that the accessibility summary is used to explain how the visuals are and are not described in the alternative text. This book can be read in a number of ways, thus the long list of accessModeSufficient entries.

<script type="application/ld+json">
{
"@context": "http://schema.org/",
"@type": "Book",
"name": "Alice in Wonderland",
"accessMode": ["auditory", "textual", "visual"],
"accessibilityFeature": ["alternativeText", "synchronizedAudioText"],
"accessModeSufficient": [
{
"@type": "ItemList",
"itemListElement": ["textual"], 
"description": "See the text"
},
{
"@type": "ItemList",
"itemListElement": ["textual", "visual"], 
"description": "See the text and images"
},
{
"@type": "ItemList",
"itemListElement": ["auditory"], 
"description": "Hear the text and image descriptions"
},
{
"@type": "ItemList",
"itemListElement": ["auditory", "visual"], 
"description": "Hear the text and see the images"
},
{
"@type": "ItemList",
"itemListElement": ["auditory", "visual", "textual"], 
"description": "Hear the text; see the text and images"
}
],
"accessibilitySummary": "Short descriptions are provided; long descriptions of the images are not needed for most readers."
}
</script>

Tools for accessible EPUB

Resources for accessible EPUB

Resources for ONIX

Resources for MARC21