Proofing EPUBs from Third-Party Vendors

Learn about common issues and errors to look out for when working with third-party ebook conversion vendors.

  • Subject(s):

    Ebook Production

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Working with third-party conversion vendors is a popular option for many publishers who may not have the capacity or resources for in-house ebook production. It is important to assess the vendor’s accessibility practices when first establishing a working partnership—the Introduction to Third-party Production of Born-Accessible Ebooks resource provides some great questions to ask vendors to determine their current practices. This resource builds upon the introductory article and discusses some common issues and errors to look out for when proofing ebooks from third-party vendors.

Common Issues and Errors in EPUBs from Third-Party Vendors

The two main areas that always pose problems in third-party created EPUBs are image descriptions and language tags. As discussed in many other resources, it is best if alternative text and extended descriptions for images are created by the author of the publication. The next best option is for the descriptions to be created by editors, subject matter experts, or other in-house staff. The same goes for language tags; it is best if publishers make note of words or phrases throughout the text that are in a different language and identify the specific language they belong to, so that the conversion vendor can accurately tag the language shifts.

If publishers request third-party vendors to create image descriptions and identify language shifts, this lengthens the quality assurance process significantly on the publishers’ end. Often, many inconsistencies and inaccuracies arise in alt-text created by third-party vendors. Moreover, language tags are often detected and applied by automated software that isn’t very accurate, and sometimes inapplicable to words that have become part of the primary language’s vernacular. For example, the word “rendezvous” does not need a French language tag in an English language publication.

Below is a list of common issues to check for in EPUBs from third-party vendors. While it is not a comprehensive list, it offers a good start. We encourage publishers to add to the checklist and complete thorough quality assurance for all their ebook conversions.

Navigation and Content Files (XHTML)

Metadata (OPF)

Styling (CSS)

Download the Checklist

Click the button below to download a PDF file of the checklist.

Next Steps


Final Quality Assurance (QA) Pass

Quality Assurance of Completed Ebooks

Once your ebook has been created, it is time to do a quality assurance check for accessibility. This resource contains both simplified and advanced checklists to help you review your ebooks.

Subject(s): Ebook Production
Resource Type(s): Checklist

External Links to More Information

EPUB Type to ARIA Role Authoring Guide

This document addresses key authoring differences to be aware of when using epub:type and ARIA role attributes in EPUBs. It also offers specific guidelines for the use of ARIA roles.

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