This document provides an overview of steps that can be taken to improve the accessibility of documents when working with Adobe InDesign. To create it, our team of accessibility testers experimented extensively with InDesign, and used two main sources: the Adobe InDesign User Guide, and Laura Brady’s online course, “EPUB Accessibility Using InDesign”, available on Lynda.com. We highly recommend checking it out; it visually presents the creation of an accessible EPUB, and is an incredibly well made course.

Introduction

Adobe InDesign is a desktop publishing application that facilitates the creation of print and digital media documents such as books, pamphlets, and brochures. It is capable of producing PDF, EPUB, HTML, and other formats. It supports XML, style sheets, and other markups, which makes it suitable for exporting tagged text content for use in digital formats.

Please note that this guide covers the work that can be done in InDesign, and does not fully discuss all of the post-export steps needed to optimize the file and make it fully accessible. The instructions in this document are meant as an overview or guide, and are intended to help publishers and ebook developers create EPUB Publications that conform to the requirements for EPUB Accessibility. This is not an exhaustive list of steps to ensure that EPUB files conform to all accessibility standards.

This guide includes topics such as how to add semantic tags, image descriptions and other features. It is meant as a starting point for using InDesign to create EPUB files that are accessible to everyone.

All instructions in this document are based on InDesign version 15.0.1. Please refer to InDesign’s manual for more details.

A note about styles

Styles are essential in defining the appearance of content in a document, and they help make broad changes throughout a file efficiently. InDesign uses styles similar to the way HTML pages use cascading style sheets (CSS). With InDesign styles, it is possible to keep the semantics and structure of the document, for the most part, separate from its visual appearance.

It is possible to apply a single style to many parts of the document, streamlining and simplifying the task of ensuring visual consistency throughout. If you need to change the appearance of the document, for example, by switching to a different font size or type, you would only need to change the style. This would automatically update all locations where that style is applied. You would not have to update all of the individual instances of that font within the document.

1. Export Publications as a Reflowable EPUB 3.0

Exporting your publication as a reflowable EPUB 3 is a simple step that is crucial for creating an accessible EPUB. The EPUB 3 format is backwards compatible, meaning that almost all reading systems will accept an EPUB 3 file. EPUB 3 is desirable because the file includes properties similar to a responsive website. It allows the content to fit screens of different sizes and shapes, such as portable tablets and mobile phones. It also makes it possible for reading applications to include adjustments in font types, sizes and colours. colour themes, margins and line spacing. Plus it allows the publisher to include EPUB 3.0 semantics, which allows you to add valuable navigational information for people who are using text to speech and screen readers.

To export as a reflowable EPUB 3:

Go to “File” in the top menu.
Select “Export…”.
You will be prompted to save the file on your computer. Under “Save as type”, select “EPUB (Reflowable).
Click “Save”.
The “EPUB – Reflowable Layout Export Options” window will open.

Go to the “General” tab (default tab):

Under Version: Select “EPUB 3.0”
Leave Navigation TOC set to the default, “Multi Level (TOC Style)”. You don’t want to create navigation based on your file names as that won’t be user-friendly!
Leave “Split Document” checked (default). This is important so that your ebook is not exported as one large HTML file. If you have indicated where to split the document when you created your “Paragraph Styles”, at an earlier stage, then leave the default setting “Based on Paragraph Style Export Tags” checked, and you can click “OK” to complete this process.
It is recommended to have a new HTML file for each top level heading or major section of your book, so if you didn’t indicate where to split your document as described above, Select “Single Paragraph Style” and choose whatever you created as your top level heading, for example, “Heading 1 or <h1>>.
Note: This will only work properly if you have tagged all your headings correctly!
Click “OK”.

For more information about these options, refer to Adobe’s InDesign guide on Reflowable Layout Export Options.

2. Add HTML 5 Semantic Tags

Semantic Tags give additional information to the structure of the EPUB to aid navigation. Simply put, the semantics give more meaning to a tag. Through InDesign, you can add a number of semantics from the “Object Export Tags” menu; however some important EPUB semantics like <section> may be easier to add editing the HTML directly.

The “Edit all Export Tags” menu can be found in the “Character Styles”, “Paragraph Styles”, and “Object Styles” menus by clicking on the menu icon at the top right of the styles pane. Then click “Edit all Export Tags” which you will find on the drop down menu.

2.1 Objects

There are a number of “Objects” that you can add HTML5 tags to, to make them clearer to persons using screen readers, namely, Section, Figure, Figcaption, and Aside. So, rather than leaving the object tagged as “Automatic” or choosing an existing tag from the drop down list , you can add the HTML5 tags, “Section” to the “Section” object, “Aside” to the “Sidebar” object, “Figure” to the “Figure” object, and “Figcaption” to the “Figcaption” object. It may seem strange that you are entering the same word of the “Object” for a tag, but this will make much more sense when you see it, as you are making these changes.

To do this:

Open the “Edit all Export Tags” window which you can access from the menu on the Paragraph, Character and Object Styles pane. (described above)
Go to the bottom of the list to the “Objects” you have added to your document. The “Objects” are represented by a small square icon, made of squares, (just below the “Character” icon which is an upper case “A”).
In the next column to the right of the “Object” that you want to edit, the “Tag” column, click on the tag. It will be highlighted, and an arrow to indicate a drop down menu will appear. Here you can choose a tag from that menu, or highlight the existing choice and type in your own HTML5 tag.

2.2 Character Styles (Emphasis, Italic, Citation, Bold, and Strong)

You can also add HTML5 tags to some “Character” styles to make them more meaningful to screen readers.

Examples of some Character Styles in a print document are bold and italics, which can be used to indicate emphasized words, phrases, or sentences. It is important to differentiate between words which require verbal emphasis and those that do not, as they require different styles. Review the Bold/Italic and Emphasis/Strong sections in NNELS’ EPUB Semantics document to learn more about when to use the correct tags.

To make your content accessible to all, you will need to create “Character Styles” with the appropriate HTML5 tags.

Here are a few examples of how to do just that. Namely, creating an Emphasis (“em”)style and tag, a Citation (“cite”) style and “cite” tag, and a Strong (“strong”) style and tag.

Note: for text that does not require verbal emphasis, you can simply use regular Italics and Bold styles.

Create new Character Styles for Emphasis, Citation, and/or Strong. Begin by opening the “Character Styles” pane.
Click on the menu icon on the top right and choose “New Character Style”.
Under the “Style Name”, type your style name (Emphasis, Citation, or Strong).
Set up your font type and other print styles by clicking on “Basic Character Formats”. These format settings will not have any effect on how a screen reader voices your text.
Add your “em”, “cite”, and “strong” tags by clicking on “Export Tagging” at the bottom of the list on the left side.
In the “Tag” field, double click on “Automatic” to highlight it.
Type in the corresponding tag name
Click “OK”

You can also add the tag from the “Edit all Export Tags” window.

Note: “Character Styles are denoted by the capital “A” in the “Edit all Export Tags” list.

3 Tagging your Headings

3.1 Starting with an Unformatted Document or Creating New Paragraph Styles in an Existing Document

When starting with an unformatted document and want to add and tag new Paragraph Styles, here are the steps to take:

Open the Paragraph Styles pane by pressing F11, or from the main menu, select “Type”>“Paragraph Styles”.
Click on the Menu icon, at the top right of the Paragraph Styles pane, and select, “New Paragraph Style”.
From the “New Paragraph Style” Window in the “General” tab that you will see at the top of the column on the left, give your style a name, such as “Chapter Title”

3.2 Tagging your Paragraph Style:

Click on the “Export Tagging” link at the bottom of the list on the left side window.
Where it currently says “Automatic” choose an appropriate HTML tag. For example, a “Chapter Title” which is normally a top level heading, choose “H1”.

You can also format the Paragraph Styles to have the appearance you desire. These visual changes will not affect the heading tags (h1, h2, h3, etc.) and, when you make a format change, all the items that you have tagged with that specific Paragraph Style, will be updated at the same time.

To do this:

Click on the “Basic Character Formats” link, the second link down on the list at the left.
Select “Font family, “Style”, “Size”, “Leading”, “Kerning” and other type settings.

As you apply Paragraph Styles to text in your book, it is very important to also ensure that every heading in the book maps to a heading tag in the ebook’s HTML code. To learn more about headings and how to correctly use them, see the following Accessible Publishing Best Practices link, below:

Accessible Publishing Best Practices.

3.3 Splitting the Document

You can decide if you want to split the document (EPUB) at a certain style/heading level. For example, it is good practice to have a separate HTML file for each level 1 heading of a book. In our example, if you want every chapter to be in its own HTML file, you can do this from the “Edit all Export Tags” window, or from the “Paragraph Styles” pane.

Open the “Paragraph Styles” pane (described in Step 1 of this document)
Click on the menu at the top right.
Click on “Edit all Export Tags”
In the “Edit all Export Tags” Window, check the “Split EPUB” checkbox which is located two columns to the right of the “Paragraph Style” that you want to use to split the document. Often this Paragraph Style: will be a Chapter Title or have an <h1> tag.

Alternately, you can:

Open the “Paragraph Styles” pane,
Double click on the “Paragraph Style” you will be using to split the document. This will open the “Paragraph Style Options” window.
Click on the “Export Tagging” link, at the bottom of the menu on the left hand side.
Check the “Split Document (EPUB only)” checkbox that is near the bottom of the page.
Click “OK”

3.4 Class tags

You can also add a “Class” tag, such as “Chapter Title” or “CT”, which will help your document have cleaner code and will keep its structure more uniform throughout. To do this:

Open “Edit all Export Tags” window (describe above in “Splitting the Document”).
Click on the blank space in the “Class” column in the same row to the right of the name you assigned to the “Paragraph Style to reveal an empty text box.
Type in the class tag into the text box.

3.5 Document with existing Paragraph Styles and formatting

Working on a document that has existing Paragraph Styles and formatting, for example a document that was “Placed” from Word into InDesign, is essentially the same. To make changes to any existing style:

In the “Paragraph Styles” pane, right click on the Style that is already present on your list.
Choose Edit (which is followed by the name of the heading you’ve just chosen. The “Paragraph Style Options” window will open.
You can then apply any of the steps that are described in “Starting with an Unformatted Document…” above.

3.6 Using “Edit all Export Tags”

You can view and modify all of your export tags in a single window by doing the following:

Select “Edit All Export Tags” in the Paragraph, Character, or Object style panel menu.
Click the EPUB and HTML tab (this is the default).
You can select or enter the HTML tag that you want to map to, for each style. You can also select and unselect the styles that you want to split the EPUB at.

3.7 Tag your other styles

It is very important that you correctly tag the structural elements of your document, such as block quotations, emphasized text, and strong text. When you do this, software like screen readers and text-to-speech are able to correctly interpret and read the content.

Open “Edit All Export Tags”
On the line of the element that you want to tag, click on “Automatic” in the second column, the “Tag” column. This will open a text box, with the word “Automatic” now highlighted.
Type in your tag. For example, “Em” for emphasized text.

You can also map a character style in this window, following the same steps. The “Character styles” are indicated on the list by the capital letter “A”.

3.8 Tag your context breaks

Context breaks, like headings and other styles mentioned above, are important to identify and map to their proper HTML tag <hr>. Visually it will appear as a horizontal line in the document, but to reading systems (since HTML 5), the <hr> tag semantically defines a thematic break in the text. Screen readers will indicate this either verbally or by causing a pause.

3.8.1 Tagging your Context Breaks

Create a new Paragraph Style by following steps 1 to 3 under Section 3.1: “Starting with an Unformatted Document…” at the top of this section.
Name the new Paragraph Style something appropriate, like “Break”.
Double click on the paragraph style. This opens the “Paragraph Style Options” window.
Go to the “Export Tagging” tab.
In the “Export Tagging” section under “EPUB and HTML”, type hr into the “Tag” field. (hr is the HTML code for “horizontal rule” and it is what tells screen readers to pause for a break)
Click “OK”.

3.8.2 Placing your <hr> (Horizontal Rule)

The next step is to place an actual “horizontal rule”, or line in the spot in the text where you want the context break to occur. To do this:

Place the cursor on a blank line between the portions of text where you want to create the context break. This is important! If you don’t place the horizontal rule (hr) this way, you may find that each time you enter a new line an hr will be created. If this occurs, simply repeat Steps 2 to 4 below, and in Step 4, click to disable the “Rule On” box.
Open the “Paragraph” pane (not the Paragraph Styles” pane), by pressing Control + Alt +T / Option + Command + T at the same time, or by clicking on “Window”, on the top menu, then click on “Type and Tables”, and then “Paragraph”.
Click on the menu at the top right of the “Paragraph” pane and select “Paragraph Rules”.
Click the “Rule On” top right of the “Paragraph Rules” pane.
Click “OK”

3.8.3 Applying the Paragraph Style

You should now see the horizontal line in the body of your document. The last step is to apply the HR “Paragraph Style” to the line. This will ensure that the <hr> tag is placed in the EPUB when you export it, so there will be an accessible context break for all. To do this:

Place your text cursor at the beginning of the horizontal line that you just created.
From the “Paragraph Styles Pane” click on the “HR” style that you created earlier.

You’re done!

3.8.4 Note

It is not possible within InDesign to remove the visual presence of the horizontal rule (line). This can be accomplished by and edit in your CSS. Learn more about Context Breaks from the DAISY Accessible Publishing Knowledge Base.

Laura Brady’s course has an excellent demonstration of this in the section “When not to describe an image”.

4 Image Descriptions

Adding alternative text to the images in your publication makes them meaningful to people who are using screen readers. This can easily be done by following the steps below:

Select the image by clicking anywhere on the image frame.
From the main menu select “Object”>”Object Export Options”. You can also right click on the selected image and choose “Object Export Options” from the drop down menu.
At the top of the Object Export Options dialogue box, select “Alt Text”. Select “Custom” as the “Alt Text Source”, and type in the text in the box below.
If the image is purely decorative, and does not add any new meaning or information for the reader, you should apply an empty alt tag (alt=””).

4.1 Important Notes

You should also add the ARIA role, (role=”presentation” to the <img> element. This step has to be done post export. For more information on using ARIA roles, check out NNELS’ EPUB Semantics, ARIA Roles, & Metadata.

Note: InDesign automatically adds an empty (alt=””) tag to the code of all images placed into the document.

4.2 Longer Image Descriptions

For longer image descriptions, alt text is not a good option since there is little ability to control the flow of that text in a screen reader. For example, if you pause the narration, when you restart it, it returns to the beginning of the description.

For more information on applying long image descriptions, see NNELS’ Technical Guidance for Long Description.

5 Table of Contents (TOC)

It is very important to have a complete and accurate table of contents that a reading system can present to the reader in a format that is understandable and navigable.

The steps below will help you do that. There are quite a few steps but it isn’t as complicated as it looks!

In InDesign, the ebook’s Table of Contents (TOC) is created from the Heading structure which you created when you set up your Paragraph Styles. Before carrying out the steps below, it is important that you establish Paragraph Styles for the elements in your document that will be used to create your TOC, such as, Chapter Titles, Subtitles, and the title for the Table of Contents itself (such as “Table of Contents” or “Contents”), before continuing with these steps. Refer to the Section 3, “Tagging Your Headings”, above, for more information on correctly implementing paragraph styles. Properly structured and tagged headings will produce a table of contents in the code of the file that is navigable in the code of the book.

You will also need to create separate styles for the TOC Chapter Titles, Subtitles etc. that will be applied to the TOC after it is created. These will be used for the TOC that is presented visually within the body of the book. You might name these, “TOC Chapter Heading-post” and, “TOC Subtitle Heading-post”. This step is included below. Note that these particular paragraph styles should NOT have a specific tag applied.

Note: There is a step below that explains how and where to enter a TOC Title. This does not have to be done in the body of the document.

5.1 Setting up your Table of Contents

Go to “Layout” on the top menu.
Click “Table of Contents”.
In the “Table of Contents” give your TOC a Title, for example it can be simply be “Table of Contents”, or “List of Figures” etc.
To the right, under “Style” choose the paragraph style you created previously for your TOC title (not the “TOC Chapter Heading-post”) by clicking on the arrow on the of the “Style” box.
Below that you will see the “Style in Table of Contents” pane. On the right side of that pane under “Other Styles” you will see the list of your heading styles.
One by one, select each paragraph style you created for the TOC elements, and then click on the “Add” button. Make sure that the headings for the different levels of the TOC cascade properly, and are in the appropriate hierarchical order. For example, “Chapter Title” (h1) appears first for top-level content, followed by “Subtitle” (h2) followed by lower-level child sections, which should have been given h3, h4, etc., tags.
Note: You will see that the styles you created for using after creating the TOC, (the “post” tags) are listed here. No action is needed on these styles until the last step (Step 12, below).
Next, one at a time, highlight each paragraph style, listed under “Include Paragraph Styles”.
Then, with that style highlighted, just below in the “Entry Style” field, select the same (matching) paragraph style name. Do this for each style on the list above.
Below that, you will see a “Page Number” field (note: you may need to click “More Options” to enable this), where you can choose whether to place numbers before or after the elements in your TOC, or to not have numbers at all. Make this choice for each style, just after you have carried out Step 8 above.
Under “Options”, just below the “Page Number” field, check the “Make text anchor in source paragraph” option. This will ensure that your table of content items are hyperlinks, so readers can click on them to be taken directly to that section of the book.
Click “OK” to exit the, “Table of Contents Styles” window.
Place your Table of Contents into the document:
1. You will now see a text cursor that is loaded with your TOC. Click on a newly created page (which you can add even when the cursor is loaded), or on a point in the document where you want to place your TOC. You will now see your new TOC.
2. The last step is to apply the appropriate tags to each items in the new TOC, for example, the TOC Chapter Title-post” tag to the Chapter titles in the TOC. You can do this by selecting each separate line of text (eg. “Chapter 1”) and via the Paragraph Styles pane, click on the style to apply it.

Your document and your Table of Contents should now be in good shape to export to EPUB!

5.2 Note

For further details, see “Create a table of contents” in Adobe’s InDesign. Following the basic Table of Contents steps provided in Adobe’s guide will create a well-formatted, accessible Table of Contents.

6 Footnotes and Endnotes

It is easy to insert footnotes and endnotes using InDesign. The footnotes and endnotes will automatically link and back-link, allowing for easy navigation.

Select the point in the document where you want to attach a footnote or endnote to.
Right Click to reveal a drop down menu. You can now click on footnote or endnote, depending on which one you want to add.
If you are adding a footnote, fill in the information in the footnote field that is displayed at the bottom of the page.
If you are adding an endnote, fill in the information in the endnote field, which will appear at the end of your document.

You will need to add an ARIA role to your footnotes after exporting to EPUB 3.0. InDesign exports the footnote in a <span> tag so some changes in the HTML are needed.

A footnote or endnote should be encased in an <aside> tag. This tells assistive technology that this text is supplementary content. Next, an epub:type of footnote or endnote identifies them to the reading system, and an ARIA role of doc-footnote or doc-endnote, identifies it to assistive technology. These three specifications allow your footnotes and endnotes to be found by the reader and displayed by the reading system, without ever disrupting the main narrative.

For more information see the DAISY Accessible Publishing Knowledge Base on the use of Footnotes and Endnotes.

7 Tables

You can create a simple table with InDesign, but it will not automatically be fully accessible. Column headers, which are very important to accessibility, do not appear in the form of code necessary to be voiced by screen readers when exported to EPUB. These must be added manually.

To create a table:

Click on “Table” on the top menu
Select “Insert Table”
From the “Insert Table” menu, select the number of “Body Rows”, “Columns”, “Header Rows”, and “Footer Rows”.
Click “OK”.

Once you have created your table, you will need to use a text editor, post export, to make changes to the HTML code.

Column headers should be denoted in HTML with the <th> tag, whereas column data is denoted with a <td> tag. In order to work, column headers should occupy the first row of the table, wrapped in <th> tags like this:

<tr>
<th>City</th>
<th>Population</th>
</tr>

A table caption is like a title that can be placed above the table. This can give the reader an indication of the contents of the table. However, it is not possible to add a caption to a table that will export to EPUB 3.0 from within In Design.

Adding a caption will enhance the accessibility of a table, so manually adding to the code is recommended.

Another possibility is to add text description to the document, just before the table.

For more information on how to add a table and captions to your document, please see:

8 Hyperlinks

All hyperlinks in your ebook should be active and linked. Hyperlinks should be in the customary blue font colour and underlined, which is the default style in InDesign

To hyperlink text:

Select the text that you want to link.
Right-click on the text.
Click on “Hyperlinks”
Select “New Hyperlink…”
Enter the URL into the URL field. (The default setting is to link to an external URL). Note: You can also create hyperlinks to link to internal points in the document, such as a page or text anchor.
Click “OK”

9 Primary Language

You can set your documents default language by following the steps below:

With no documents open, Open the “Character Panel” by selecting “Window” from the top menu.
Click on “Type and Tables” and you will see a drop down menu that reveals, “Character”. Click on “Character”.
With the “Character” pane open, you can choose your language from the list at the bottom.
Open the “Paragraph Styles” pane by clicking on “Type” on the main menu, and then clicking on “Paragraph Styles”.
From the “Paragraph Styles” pane, double click on “Basic Paragraph” in the Style Name box. That will be the only one listed since there is no open document. If there is a “plus” sign next to the words, “Basic Paragraph” this indicates an “override” or a discrepancy (two different languages), but it will automatically disappear after you double click on “Basic Paragraph”.
From the “Paragraph Style Options” window, Click on “Advanced Character Formats” which is on the menu to the left.
Choose your Primary Language by clicking in the down arrow on the text box at the bottom.
Click OK.

The language will now default to the language you’ve chosen.

If you have large paragraphs or large sections in your book written in a different language, you can create unique “Paragraph Styles” for that language, in the usual way, which is described in the “Tagging Your Headings” section (included in this document, above), and then apply steps 6 and 7, (above), to change to the appropriate language.

If you just have short phrases or sentences of a different language that appear in your book, it is best to declare a language shift. Please see the Declaring Language section.

10 Language Shifts

It is important to declare Language Shifts in your document. For example if you have a sentence in French such as “Je voudrais un café” in your text, it would be quite annoying to have it pronounced in English. You can remedy this issue by doing the following:

Select the other language text, In this case French text.
Open the “Character Styles” pane and click on the menu at the top right.
Choose, “New Character Style”.
From the “New Character Style’ window, give the new style a name. In this case you might use “FR” to indicate French.
Style the text if you wish: Click on the “Basic Character Formats” on the list on the left and choose a “Font Style”. Most likely you would select “Italics”.
Click on “Advanced Character Formats” on the list on the left. At the bottom you’ll see the “Language” text box. Here you can declare your language. Choose “French”.
Click “OK”.
With the text still selected, return to the Character Styles pane and click on the name of the new style (“FR”) that you just created.

Now when you export your document, the French phrase “Je voudrais un café” will be pronounced correctly!.

11 Lists

You do not need to map paragraph styles to the text of bulleted or numbered lists when creating a bulleted or numbered list in InDesign. Semantic, properly formatted lists should always be used (instead of manually setting up text to look like a list using methods like indenting or adding special characters for bullets)

To make a list in InDesign:

Place your text cursor where you want to insert a list.
Go to “Type” on the top menu.
Select “Bulleted and Numbered Lists”.
Select “Apply Bullets” to create an unordered list, or “Apply Numbers” to create an ordered list.
Enter the text into the document.
When you have finished your list, return to Type>Bulleted and Numbered Lists and choose “Convert Bullets and Numbering to Type”

Note: To turn existing text into lists, simply highlight the text that you want to convert and follow steps 2 to 5 above. In this case there is no need to do Step 6.

For more information on using lists, see the Adobe help page “Create bulleted or numbered lists”.

12 Metadata

12.1 Enter all the metadata

InDesign lets you add the barebones essential metadata to your EBook, such as title, author, publisher, date, etc. Unfortunately, the all-important accessibility metadata, discussed in a separate section below, must be manually added, outside of InDesign to the end of the metadata in the .OPF file. It is not a difficult process, and is explained below. First, the basic metadata:

You can add the metadata during the “Export” process:

Go to “File”.
Select “Export…”
Save as “EPUB (Reflowable)”. The “EPUB – Reflowable Layout Export Options” window will open.
Go to the “Metadata” tab situated in the list on the left side of the Window.
Enter the following essential information: Title, Creator, Date, and Publisher.
Click “OK”.

12.2 Add accessibility metadata

Accessibility metadata provides important information for publishers and libraries, on the accessibility features of a publication. It also defines how users can access your data, and can alert them to any hazards, such as flashing lights or loud sounds that they may encounter when reading. For more information on this go to the links below check out the W3C’s “Discovering Accessible Content”.

Including accessibility metadata in your publication is not as difficult as it looks. If you have a list of the Schema.org statements, you can simply copy and paste the appropriate code n to your EPUB’s .OPF file. Take a look at NNELS’ Metadata Guide for more information and examples.

More information and a list of the Schema.org accessibility statements can be found on the DAISY Accessible Publishing Knowledge Base: Schema.org. This link also includes information on how to place the accessibility metadata into your .OPF file. You may want to use Ace by DAISY’s metadata editor to add accessibility metadata to your EPUB. You can find more information and a link to download it, here: Ace by DAISY.

13 ARIA Roles

An important addition to EPUB 3.0 semantics is ARIA roles or Accessible Rich Internet Applications. Since the release of EPUB version 3.0, ARIA Roles can be added to EPUB 3.0 files to make navigation easier for assistive technologies such as screen readers. They add more content and meaning, and can add useful navigation information that is not always picked up or present in the HTML. Assistive technologies understand ARIA roles but do not always understand epub:type semantics.

Adding ARIA roles to EPUB files is not currently possible within InDesign. However, you can add some epub: type semantics to get the ball rolling.

Create an object like a basic text frame or basic graphics frame.
Select the text or graphics frame and right-click on it to reveal a drop down list where you can choose “Object Export Options”
Make sure the “EPUB and HTML” button at the top of the “Objects Export Options” window is selected. Normally, this is the default setting.
In the “epub:type” text box, type in your semantics.
Click “Done” at the bottom of the window.

Content within the frame should then be exported to content inside a div tag that has an associated epub: type.

Note: Unfortunately, not only is this procedure a bit complicated, but the code it produces still needs work. It might just be easier to add the epub:type semantics, along with the ARIA roles, to sections post-export.

For more information on selecting and implementing ARIA roles, check out NNELS’ ARIA Roles guide.

For a list of ARIA Roles please see the W3C’s Digital Publishing WAI-ARIA Module 1.0: Role Definitions.

14 Tip on Avoiding an Export to EPUB “Styles” Error

Style collisions (when styles merge and become one tag upon export) can occur when exporting your InDesign document to an EPUB 3.0 reflowable EPUB, if you use an “Illegal” CSS character in a Style name. This includes the following characters: ~ ! @ $ % ^ & * ( ) + = , . / ‘ ; : ” ? > < [ ] \ { } | ` #. Beginning a style name with a number (such as “1-Name) is also illegal, and can cause a Style collision.

Letters, underscores, hyphens, and numbers (so long as they do not start the Style name) are all legal.

To fix/avoid a Style collision, edit the names of the Styles to remove the illegal characters, or, in “Edit all Export Tags”, add a unique class name to each Style.

15 Beyond InDesign

With InDesign it is possible to create accessible body text content and simple image descriptions, and add semantic tags, headings, and paragraph styles to produce clean, semantic EPUB files. However, to obtain a fully accessible EPUB, additional manual work on the exported file is necessary, such as adding ARIA roles, cleaning up code for a table, and adding accessibility metadata (note: these items are all discussed in this document). Post-export clean-up tasks will need to be done outside of InDesign, using a program such as the Sigil application or an HTML editor to manipulate the document, and to address some accessibility features, such as those techniques outlined by the W3C’s WAI-ARIA, the Accessible Rich Internet Applications.

Page lists, another very important feature of accessible EPUBs, must also be created outside of InDesign. It is important for ebook developers to be aware of these limitations, and take steps to further optimize accessibility of their EPUB files.

16 Further resources

Laura Brady’s Lynda.com course: EPUB Accessibility Using InDesign
DAISY’s Webinar: Leveraging InDesign for Accessible EPUB Creation webinar
EPUB Secrets

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