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This page contains accessibility features that fall into the following categories.
The following recommendations contain a non-exhaustive list of accessibility features that can be included in ebooks. It builds on an earlier Best Practices document written by the NNELS team, which continues to be expanded. Wherever possible, the recommendations below are linked to their corresponding section in that document: Accessible Publishing Best Practices: Guidelines for Common EPUB Issues in Plain Language.
A key to building accessibility into publishing is to take it on incrementally, if this is all your time allows for. If you only have time to image descriptions, or mark up sections with structured headings, then you have made your book more accessible by leaps and bounds! As evidenced by this list, as well as many other guides and resources you have probably seen, there are tonnes of accessibility features that can be built in to books, and the best thing to do is dive in – no matter the size of step you can take right now.
Note: Items in the below checklists are ranked by importance. The first section includes recommendations that will be helpful to publishers of all genres, and there is additional information for publishers of non-fiction material and children’s books, and a brief discussion for publishers of poetry.
The following guidelines apply to all electronic publications. This general list lays the foundation for a well-designed ebook, relevant for all genres and publishers. If a publisher follows these recommendations, they will be able to create an almost perfect ebook for a simple format like a novel.
- Choose reflowable format. Fixed layout books are challenging to navigate, difficult to understand and impossible to customize. This creates an enormous barrier for all readers with print disabilities. Choose reflowable, whenever possible.
(Of course, this is not always feasible for more image-heavy books – and that’s ok! Check out the Children’s section below to learn a way to improve the experience)
- Publish in EPUB 3. Because EPUB is based on the language of the web (HTML 5), it is more accessible than any other format. The very best experience comes from the latest version of the specification as it includes rich navigation, presentation and accessibility features. EPUB 3 files are widely accepted, and are far more scalable than their version 2 predecessors.
- Describe and mark-up images. Alternative text tells readers with print disabilities what is happening in a photo or figure. Without sufficient descriptions, those who cannot see pictures will have no access to their content.
Image descriptions should be provided for all non-decorative images, including the cover page.
It is recommended to use extended descriptions for complex images such as graphs. Also, decorative images needed to be given the ARIA role of “presentation” role, so assistive technology can skip over them (See Example 5 on the Accessible Publishing Knowledge Base).
Visit NNELS’ Image Description Guide for help with image descriptions.
- Use text. It may be tempting to set the title page (or a complex table) up as an image, but we strongly recommend never setting text as an image, in all cases. Even well-described images are less accessible than text.
- Include headings. Every section title in the book should be set up as a heading, including sections in the front and back matter. Headings tell readers that a new section has begun, and specify its title. Headings also provide valuable navigation points for non-traditional readers. For this reason, only use headings at the start of a section, never just for style. Headings must be indicated with semantic code, i.e., <h1> <h2> etc.
- Cascade headings. Heading levels should be used to indicate the importance of a section. The titles of top-level sections should be assigned a level-one heading. Content under a main section should be introduced with a level-two heading, and child sections should be headed with a level-three heading. This brings clarity to the structure of a book, making it clear where the user is in the reading order. Also, take care to use only one heading per section, encasing the chapter number and title in a single set of heading tags for example.
- Link to all sections from the table of contents. Reading systems use the book’s navigation file to move efficiently through the content. Sections that are excluded from the navigation file, therefore, are difficult or impossible to access. The goal is to link to every section in the book – even front and back matter – so it can be easily navigated from cover to cover. A sound heading structure will assist a reader greatly.
Similarly, best practice is also to link back to the table of contents from the chapters/sections within the text.
- Include a textual Table of Contents. Readers use a Table of Contents to familiarize themselves with the content of a book. It is thus really valuable to include a table of contents in the front matter. This page should be set up as a list, with active links to each section.
- Emphasize text properly. The tags that are present within the ebook offer semantic meaning to assistive technology. As a result, it’s important to mark words that should be vocally emphasized, so synthesizers can pick up on this inflection. It is important to ensure that emphasis is only placed on such passages, and not just on all italicized words. This is a job for the author and editor, but care must be taken to preserve (and not change) these valuable tags throughout design and conversion to EPUB. If you work with InDesign, learn more about how to do this here: Working with InDesign.
- Avoid dropcaps. Whenever a screen reader encounters a change in text style, it treats it as a new sentence. A dropcap on the word “the”, therefore, causes it to be read as “t he”. Use a different presentation layout than dropcaps.
If you want to retain dropcaps, there is a way to code them so that they are read naturally. See an example of this code in our Best Practices: Dropcaps.
- Use title case instead of all caps. Because text-to-speech engines are trained to spell out acronyms, many systems will spell out all uppercase words, one letter at a time. This is frustrating to listen to and makes the text extremely difficult to comprehend when the first line or sentence of a chapter appears in all caps. As a good rule of thumb, uppercase words should be avoided entirely. Important words in titles should only have the first letter capitalized. Accurate, semantic tags for emphasis and italics should be employed to offset important phrases.
- Include accessibility metadata. Metadata can tell potential buyers and readers what accessibility features the book offers. These features range from basic text access to full semantic markup and described images. For help on getting started or improving your accessibility metadata, visit NNELS’ Simplified Guide to Accessibility Metadata.
- Title the documents. Some e-readers will announce a document’s title when a new section is opened, or on command as a kind of “Where am I” feature. As such, the title tag should always hold the name of the chapter or section contained in that document. Ensure this tag is set to announce helpful, accurate information to readers, to distinguish it from other documents in the book. Usually, the text found in the first heading of each section works nicely here.
- Specify a language in the HTML header of each document. HTML and WCAG guidelines require that the language be noted in each text document in an EPUB, as well as in the OPF.
These items will result in a highly accessible book, but there are ways to make it even more accessible! While we discuss including a page-list and tagging page numbers in the following section, as they are of key importance for more complex content, these page-based features are highly desirable for all books.
In addition to the General features noted previously, there are several elements designed specifically for research books and other non-fiction material. This is especially true for books that have endnotes, footnotes, bibliographies etc. Try to include as many features as possible.
- Link notes. Ebooks have many different ways of navigating content, and notes are a great example. Footnote and endnote numbers should be clickable, and each note should have a link to return to the text. This lets readers seamlessly peruse the notes in the book, without fear of losing their place in the chapter.
- Label table columns. As readers move through a table with assistive technology, they hear the title of the current column, followed by the information in that cell. This is made possible through table headings – column titles that appear in the top row of the table. Please title the columns of your tables, and mark them up as table headers so assistive technology can use them.
- Caption links. Hyperlinks harness the full power of electronic publishing, as they allow readers to effortlessly jump to different areas of interest. The text of such a link, however, is crucial to informing non-visual readers of its purpose. When a link is highlighted through assistive technology, only its text is spoken. For this reason, it’s important to caption links with the title of the document it points to. Also, set web addresses up as active links, wherever possible, to make them easier to find and activate.
- Include a page-list. A page-list allows readers to offer page navigation to their users, relying on anchors throughout the text to jump effortlessly to any page in the book. This layer of navigation makes it easy to find your place in a lengthy textbook or manual. If page numbers are derived from the print edition, don’t forget to specify the print ISBN in the ebook’s metadata, and refine that tag to confirm it was the source of the page correlation.
- Tag page numbers. Assistive technology can announce page numbers as it reads the text, and speak the current page number when asked. This is made possible through the use of ARIA roles. Add a role of doc-pagebreak to your page breaks, and title them with the number of the current page.
- Use semantic elements. Assistive technology relies on semantic tags to render your content properly. Specific tags exist for things like figures, sidebars, captions, and citations. Using these tags will take care of the heavy lifting on the design side of things, while providing valuable context, navigation and structure to assistive technology. From there, even greater meaning can be implied with epub:type semantics and ARIA roles. For more information, check out NNELS’ guide to EPUB Semantics, ARIA Roles, & Metadata
Books for very young readers are often heavily image-based, with specific spots in the text where pictures are designed to go. In order to match the printed edition, these ebooks usually require a fixed layout style. Fixed layout content poses numerous challenges to assistive technology, but there are some things you can do to minimize the disruption.
- Set the position of phrases (instead of individual words) wherever possible. Never set positioning on parts of a word, and include punctuation within the word boundary. This helps minimize broken words and lengthy pauses in the narration.
- Pay close attention to navigation points and the page list. Fixed layout content frequently neglects these key areas, making the book even more challenging to read.
- Consider including an audio overlay with the book. Media overlays allow publishers to bundle an audiobook edition with the text portion, and even synchronize the text with each sentence of narration. This gives non-traditional readers an accessible alternative to a book that may not work well with their assistive technology.
Artistic expression is limited only by a poet’s imagination. And where the predictably-rhyming style of Robert Service told a story in verse, modern poets have expanded their style to go well beyond the printed word. Some books anchor the first line as a title. Other works use complex spacing, line justification, and concrete poetry to increase their impact. These are sizable considerations that will require more research and in-depth study. We hope to tackle these issues in future projects.
For now, please implement as many of our general guidelines as you can. Use semantic styles like sections, horizontal rules, and sidebars to add separation to your content. Employ headings at the beginning of sections, and at the top of each poem wherever possible. In order to continue to improve the accessibility of poetry books, further research is required for this genre.