Introduction

If you're in the Open Education Network's Publishing Cooperative and choose to work with Scribe, here's information about how their workflow creates accessible (Links to an external site.) textbooks, including an EPUB3, using accessibility styles (Links to an external site.).

Overview/Goals

Accessibility involves the creation of rich, informative publications that are available to a wider audience.
Accessible publications are more useful for readers in general.
Creation of a single, accessible product from the start rather than retroactively creating accessible content based on need is not only ideal but increases the value of the publication.
ePub3 was developed with accessibility in mind (HTML5-based). Scribe's default is ePub3.

Document Structure

The following should be taken into account in accessible document structure. Scribe's Well Formed Document Workflow (WFDW) takes this into account by default:

Logical reading order (hierarchical head levels, placement of ancillary materials within flow of narrative, image/table callout placement)
Separation of presentation and content; comprehension should be solely independent from design elements; content should be digestible if no stylesheet exists; assistive technologies (AT) must be able to interpret content based on structure alone (HTML5)
Proper markup allows all individuals to distinguish headings, footnotes, sidebars, or other text elements without relying on the visual presentation
Publications composed using the WFDW are more accessible by definition
Table of contents should represent complete navigation; include secondary head levels; and should link to all tables and figures.

HTML5 and Semantic Tagging

The following are examples of HTML5 semantic tags and how ScML maps to them:

<ct> = <h1 class="ct">
<ah> = <h2 id="ahaft0101" class="ah">
<chapter> = <section>
<dedication> = <section epub:type="dedication">
<blockquote> = <blockquote>
<figure> = <figure>
<sidebar> = <aside class="sidebar"> AT can hide from main narrative
<box> = <aside class="box">
<list> = <ol style="list-style-type:none">

The following are special ScML character styles that will also map to HTML5 semantic tags, which, for example, provide a means for differentiating bold and italic used for emphasis versus presentation only:

<cite> = Citation
<em> =Emphasis, vocally stressed text
<fterm> = A foreign word or technical term used in an English context; maps to <i class="fterm">
<strong> = Emphasis for importance, as in imperative statements (“warning” or “alert”).
<tnw> = Title, name, or work; maps to <i class="tnw">

Note: Scribe WFDW maps to equivalent HTML5 tags when available since alternative technologies are built to interpret HTML5 semantic tagging. Scribe's ScML/XML-based workflow allows for more flexibility/print considerations than HTML5 based workflows. ScML can store more information for future development/electronic formats.

Page Lists

Print page numbers should be included when a print book exists; also include print ISBN in metadata. Some reading platforms allow for quick page navigation (e.g., newer versions of Adobe Digital Editions).

Alt Text

Alt text is alternate descriptions of images (with the exception of ornamental images); they are typically limited to 150 to 200 characters; longer descriptions are under development.
Scribe is currently testing a new feature of the Hub that will allow you to roundtrip (convert ScML back into Word) and maintain the alt text descriptions (docx, IDTT, ScML, ePub3).

Accessibility Metadata

For discoverable ePub3 one should add as much metadata as possible, as it provides accessibility criteria for users and search engines. The following are a couple of accessibility-specific metadata:

accessMode (textual, visual, auditory)
accessibilityFeature (alternative text, captions)
accessibilitySummary (general description of compliance with particular requirements)
accessibilityHazard (defaults to none)

Define Languages

Languages should be defined to aid assistive technologies; Scribe's Digital Hub defaults to English.

Additional Considerations

Use explicit references to figures, tables, boxes, sidebars, and so on.
Avoid directional language (above, below, opposite).
Avoid images with dense text, especially without sufficient captions (ask yourself, "If the image disappears, can content be comprehended?").
Ask, "If color is used to emphasize the importance of selected text, is there an alternate method also used?"
Lists are preferable to tables.

Best Practices

Web Content Accessibility Guidelines (WCAG) 2.0: WCAG is the internationally recognized standard for creating accessible web content, developed by the World Wide Web Consortium (W3C).
International Digital Publishing Forum (IDPF): Maintains the open standard for accessible ePub3, strives to meet WCAG standard using EPub3.
Ace Checker by DAISY Consortium: Validates ePub3 against internationally recognized standards for accessibility.
Scribe ePub3 files currently pass Ace Checker even without alt text or accessibility character styles. The use of alt text and character-level HTML5 styles are considered best practices. Consider future requests for more accessible content.

Additional Resources

(Links to an external site.)John Howkins, director of electronic book development at Scribe, describes accessibility concepts in a video (Links to an external site.) from an OEN Publishing Cooperative meeting.