Summary

Include accessibility evaluation metadata when an assessment of a publication has been performed to enable conformance discovery and provide identification of the evaluator and their credentials.

Examples

Example 1 — Package Document metadata (EPUB 3)

The following example shows a complete set of evaluation metadata for a publication that conforms to the EPUB Accessibility specification at WCAG Level AA.

<metadata>
  <link property="dcterms:conformsTo"
        href="http://www.idpf.org/epub/a11y/accessibility-20170105.html#wcag-aa"/>
  <meta property="a11y:certifiedBy">Dewey, Checkett and Howe</meta>
  <meta property="a11y:certifierCredential">Certifiably Accessible</meta>
  <link property="a11y:certifierReport"
        href="https://example.com/reports/a11y/pub.html"/>
  …
</metadata>

Frequently Asked Questions

Does the a11y: prefix have to be declared in the EPUB package document?

Technically, no, but best practice is to always declare the prefix. EPUB has a concept of "predefined prefixes", which are prefixes that can be used without being declared. In practice, however, older versions of the epubcheck validation tool will flag newer predefined prefixes as errors, as they are unaware of newer additions. Declaring the prefix ensures there will not be validation issues.

The a11y: prefix is declared as follows:

<package … prefix="a11y: http://www.idpf.org/epub/vocab/package/a11y/#">

Explanation

Evaluation metadata is used to provide additional information about the individual or organization that has assessed a publication against accessibility standards. It also allows identification of the standard(s) the publication conforms.

All evaluation metadata described in this section with an a11y: prefix are defined in the EPUB Accessibility Vocabulary.

dcterms:conformsTo

An established standard to which the described resource conforms.

The dcterms:conformsTo property provides a URL that references the standard the publication conforms to. In the case of EPUB, these conformance URLs are defined in the EPUB Accessibility specification.

The dcterms:conformsTo property is only included when a publication meets the requirements of a standard. It is not used to indicate failure. Use the schema.org accessibilitySummary property to record information about failures.

Package Document usage:
<link property="dcterms:conformsTo"
      href="http://www.idpf.org/epub/a11y/accessibility-20170105.html#wcag-aa"/>
a11y:certifiedBy

Identifies a party responsible for the testing and certification of the accessibility of an EPUB Publication.

The a11y:certifiedBy property is included in a publication when it has been reviewed for accessibility conformance. The EPUB Accessibility specification requires that this property be set even when the publication does not meet accessibility requirements.

Package Document usage:
<meta property="a11y:certifiedBy">Dewey, Checkett and Howe</meta>
a11y:certifierCredential

Identifies a credential or badge that establishes the authority of the party identified in the certifiedBy property to certify content accessible.

The a11y:certifierCredential property is used to provide more information about the credentials of the certifier to carry out accessibility evaluations.

The property can either be a text field with the name of the credential held, or it can be a link to a description of the credential.

Package Document usage:
<meta property="a11y:certifiedCredential">Certifiably Accessible</meta>
<link property="a11y:certifiedCredential"
      href="https://example.com/a11y/credential"/>
a11y:certifierReport

Provides a link to an accessibility report created by the party identified in the certifiedBy property.

When an accessibility conformance report for the publication is publicly available, the a11y:certifierReport property can be used to provide a link to it. The user agent can then offer the user the option to access this report to discover more information about the title.

Package Document usage:
<link property="a11y:certifierReport"
      href="https://example.com/reports/a11y/pub.html"/>

References