Summary

Include accessibility metadata in ONIX records so that it is available in distribution channels.

Examples

Example 1 — Sample ONIX message featuring accessibility information
<ONIXMessage release="3.0">
  <Header>
    …
  </Header>
  <Product>
    …
    <DescriptiveDetail>
      <ProductFormFeature>
        <ProductFormFeatureType>09</ProductFormFeatureType>
        <ProductFormFeatureValue>03</ProductFormFeatureValue>
      </ProductFormFeature>
      <ProductFormFeature>
        <ProductFormFeatureType>09</ProductFormFeatureType>
        <ProductFormFeatureValue>10</ProductFormFeatureValue>
      </ProductFormFeature>
      <ProductFormFeature>
        <ProductFormFeatureType>09</ProductFormFeatureType>
        <ProductFormFeatureValue>11</ProductFormFeatureValue>
      </ProductFormFeature>
      <ProductFormFeature>
        <ProductFormFeatureType>09</ProductFormFeatureType>
        <ProductFormFeatureValue>13</ProductFormFeatureValue>
      </ProductFormFeature>
    </DescriptiveDetail>
    …
    <TitleDetail>
      <TitleType>01</TitleType>
      <TitleElement>
        <TitleElementLevel>01</TitleElementLevel>
        <TitleText>Accessible EPUB 3</TitleText>
      </TitleElement>
    </TitleDetail>
    …
  </Product>
</ONIXMessage>
Example 2 — Linking an ONIX message
<package … >
    <metadata>
        … 
        <link
              rel="onix-record"
              href="#EPUB/meta/onix-9781234567890.xml"/>
        …
    </metadata> 
    …
</package>

Explanation

ONIX Code List 196 enables the inclusion accessibility compliance metadata in an ONIX message. This information can then travel with the publication through distribution channels so that customers can be made aware of the accessible features the EPUB offers. Each success criteria will be handled in turn in this section.

00: Accessibility Summary

<ProductFormFeature>
 <ProductFormFeatureType>09</ProductFormFeatureType>
 <ProductFormFeatureValue>01</ProductFormFeatureValue>
 <ProductFormFeatureDescription>
   Publication lacks image descriptions and alt text.
 </ProductFormFeatureDescription>
</ProductFormFeature>
01: LIA Compliance Scheme

Indicates that the EPUB conforms to the Libri Italiani Accessibili guidelines.

<ProductFormFeature>
 <ProductFormFeatureType>09</ProductFormFeatureType>
 <ProductFormFeatureValue>01</ProductFormFeatureValue>
</ProductFormFeature>
02: Accessibility Specification 1.0 A

Indicates that the EPUB conforms to the EPUB Accessibility specification at WCAG Level A

<ProductFormFeature>
 <ProductFormFeatureType>09</ProductFormFeatureType>
 <ProductFormFeatureValue>02</ProductFormFeatureValue>
</ProductFormFeature>
03: Accessibility Specification 1.0 AA

Indicates that the EPUB conforms to the EPUB Accessibility specification at WCAG Level A

<ProductFormFeature>
 <ProductFormFeatureType>09</ProductFormFeatureType>
 <ProductFormFeatureValue>03</ProductFormFeatureValue>
</ProductFormFeature>
10: No user agent accessibility options disabled (except)

This criteria is not specific to EPUB 3. The enabling or disabling of accessibility features lies with content producers (for example, DRM restrictions). To meet the criteria, do not bundle or distribute your publications with restrictions on them that would disable access to the content by screen users, etc.

<ProductFormFeature>
 <ProductFormFeatureType>09</ProductFormFeatureType>
 <ProductFormFeatureValue>10</ProductFormFeatureValue>
</ProductFormFeature>
11: Table of contents navigation

The requirement to include an EPUB navigation document does not, in and of itself, satisfy this requirement. A toc nav with links to the complete structure of your publication is required. See the Table of Contents section for more information. Lists of tables and illustrations must also be provided, if applicable.

<ProductFormFeature>
 <ProductFormFeatureType>09</ProductFormFeatureType>
 <ProductFormFeatureValue>11</ProductFormFeatureValue>
</ProductFormFeature>
12: Index navigation

A linked index can be provided using ordered lists to meet this criteria, but work is ongoing at the IDPF on how to embed richer indexes. See the Indexes section for more information.

<ProductFormFeature>
 <ProductFormFeatureType>09</ProductFormFeatureType>
 <ProductFormFeatureValue>12</ProductFormFeatureValue>
</ProductFormFeature>
13: Reading order

The requirement to include a spine element does not satisfy this requirement. The logical reading order of the publication must be clearly delineated in the markup. Footnotes, tables, images, sidebars and all similar secondary content must be marked up so that it can be skipped over.

<ProductFormFeature>
 <ProductFormFeatureType>09</ProductFormFeatureType>
 <ProductFormFeatureValue>13</ProductFormFeatureValue>
</ProductFormFeature>
14: Short alternative descriptions

Text alternatives must be provided for all significant images to meet this requirement. See the Images section for more information.

<ProductFormFeature>
 <ProductFormFeatureType>09</ProductFormFeatureType>
 <ProductFormFeatureValue>14</ProductFormFeatureValue>
</ProductFormFeature>
15: Full alternative descriptions

Longer descriptions must be provided for all complex images to meet this requirement. See the Images section for more information.

<ProductFormFeature>
 <ProductFormFeatureType>09</ProductFormFeatureType>
 <ProductFormFeatureValue>15</ProductFormFeatureValue>
</ProductFormFeature>
16: Visualised data also available as non-graphical data

Tabular or text equivalents must be provided for all bar graphs, pie charts and similar graphical representations of data.

<ProductFormFeature>
 <ProductFormFeatureType>09</ProductFormFeatureType>
 <ProductFormFeatureValue>16</ProductFormFeatureValue>
</ProductFormFeature>
17: Accessible math content

To meet this requirement, MathML must be included for math equations, formulas, etc.

<ProductFormFeature>
 <ProductFormFeatureType>09</ProductFormFeatureType>
 <ProductFormFeatureValue>17</ProductFormFeatureValue>
</ProductFormFeature>
18: Accessible chem content

EPUB does not provide native support for ChemML, but ChemML can be included using the epub:switch element to meet this requirement. An XHTML fallback will have to be provided, however.

<ProductFormFeature>
 <ProductFormFeatureType>09</ProductFormFeatureType>
 <ProductFormFeatureValue>18</ProductFormFeatureValue>
</ProductFormFeature>
19: Print-equivalent page numbering

If a print-equivalent of the ebook exists, the pagination can be included in the publication using the EPUB pagebreak property. To fully meet this requirement, a page-list nav also needs to be included to facilitate page-level navigation. See the Page Numbering and Page List Navigation sections for more information.

<ProductFormFeature>
 <ProductFormFeatureType>09</ProductFormFeatureType>
 <ProductFormFeatureValue>19</ProductFormFeatureValue>
</ProductFormFeature>
20: Synchronised pre-recorded audio

The inclusion of media overlays to synchronize text and audio content is sufficient to meet this requirement. The overlays should be structured in such a way that they facilitate escaping and skipping of structures. See the Media Overlays subsections for more information.

<ProductFormFeature>
 <ProductFormFeatureType>09</ProductFormFeatureType>
 <ProductFormFeatureValue>20</ProductFormFeatureValue>
</ProductFormFeature>
21: Text-to-speech hinting provided

This value indicates the inclusion of PLS lexicons, SSML tagging and/or CSS Speech properties to enhance text-to-speech playback of content.

<ProductFormFeature>
 <ProductFormFeatureType>09</ProductFormFeatureType>
 <ProductFormFeatureValue>21</ProductFormFeatureValue>
</ProductFormFeature>
22: Language tagging provided

This value is set when the language of all content documents has been specified, as well as all instances in the text where the language changes. For more information, refer to the Languages section of this guide.

<ProductFormFeature>
 <ProductFormFeatureType>09</ProductFormFeatureType>
 <ProductFormFeatureValue>22</ProductFormFeatureValue>
</ProductFormFeature>
24: Dyslexia readability

Indicates that the publication has been formatted with specialised font, character and line spacing, justification and paragraph spacing, colouring and other options provided specifically to improve readability for dyslexic readers.

<ProductFormFeature>
 <ProductFormFeatureType>09</ProductFormFeatureType>
 <ProductFormFeatureValue>94</ProductFormFeatureValue>
 <ProductFormFeatureDescription>
	Publication uses the Open Dyslexic font …
 </ProductFormFeatureDescription>
</ProductFormFeature>

The following informational fields should always be included when applicable:

94: Compliance web page for detailed accessibility information

If accessibility features, compliance and/or testing information is available on the web, provide a link to the page in this field. This information must be validated against an independent compliance scheme or the testing performed by a testing organization.

<ProductFormFeature>
 <ProductFormFeatureType>09</ProductFormFeatureType>
 <ProductFormFeatureValue>94</ProductFormFeatureValue>
 <ProductFormFeatureDescription>
	http://standards-org.example.com/book/123/compliance
 </ProductFormFeatureDescription>
</ProductFormFeature>
95: Trusted intermediary’s web page for detailed accessibility information

SImilar to field 94, but the link is to compliance information provided by a trusted intermediary or third party nominated by the publisher.

<ProductFormFeature>
 <ProductFormFeatureType>09</ProductFormFeatureType>
 <ProductFormFeatureValue>95</ProductFormFeatureValue>
 <ProductFormFeatureDescription>
	http://intermediary.example.com/book/123/compliance
 </ProductFormFeatureDescription>
</ProductFormFeature>
96: Publisher’s web page for detailed accessibility information

Similar to fields 94 and 95, but the link is to compliance information provided directly by the publisher.

<ProductFormFeature>
 <ProductFormFeatureType>09</ProductFormFeatureType>
 <ProductFormFeatureValue>96</ProductFormFeatureValue>
 <ProductFormFeatureDescription>
	http://publisher.example.com/book/123/compliance
 </ProductFormFeatureDescription>
</ProductFormFeature>
97: Compatibility tested

A record of all compatibility testing that has been performed on the ebook should be recorded in this field.

<ProductFormFeature>
 <ProductFormFeatureType>09</ProductFormFeatureType>
 <ProductFormFeatureValue>97</ProductFormFeatureValue>
 <ProductFormFeatureDescription>
	Content has been tested to work on iBooks,
	Sony User and Adobe Digital Editions in 
	both scripting enabled and disabled modes.
 </ProductFormFeatureDescription>
</ProductFormFeature>
98: Trusted Intermediary contact

If produced or distributed through a trusted intermediary, this field provides contact information for additional information about the accessibility features in the EPUB.

<ProductFormFeature>
 <ProductFormFeatureType>09</ProductFormFeatureType>
 <ProductFormFeatureValue>98</ProductFormFeatureValue>
 <ProductFormFeatureDescription>
	accessinfo@global-library.example.com
 </ProductFormFeatureDescription>
</ProductFormFeature>
99: Publisher contact for further accessibility information

The contact information for an internal representative who can provide additional information about the accessibility features in the EPUB.

<ProductFormFeature>
 <ProductFormFeatureType>09</ProductFormFeatureType>
 <ProductFormFeatureValue>99</ProductFormFeatureValue>
 <ProductFormFeatureDescription>
	accessibility-officer@example.com
 </ProductFormFeatureDescription>
</ProductFormFeature>

References

Frequently Asked Questions

Does the ONIX message have to be included in the EPUB container?

No, ONIX messages are not publication resources so can be hosted outside the container. When considering external hosting of resources, duly consider that not all user agents are connected to the internet; an accessible device may wind up without access to your accessibility information.

Can I use other metadata standards to include accessibility information?

Yes, schema.org includes a set of accessibility properties that enable accessibility metadata to be embedded directly in an EPUB package file.

How is this metadata useful?

The metadata can be used in distribution channels to allow users to discover whether the publication is suitable for their needs, as one example. A book store search engine could use the information to allow users to filter the available ebooks to only those that they know will work with their assistive technology.

The user agent could similarly present the accessibility information to the user in advance of reading even if the book has been delivered through a less accessible channel (e.g., enabling a quicker return of the ebook if it's known to be incompatible with their system).

Without this information, the user has no way to distinguish the quality of one EPUB from another.