The new W3C standards for e-books: EPUB 3.3 and EPUB Accessibility 1.1
Research and development
Research and development
by Cristina Mussinelli, Gregorio Pellegrino, Elisa Molinari, Luc Audrain
The European Accessibility Act (EAA) is an EU directive establishing binding accessibility targets that, starting from June 2025, must be met by many different types of products and services to strengthen the rights of people with disabilities to access goods and services. It is particularly relevant for the publishing industry as it includes e-books, dedicated reading software, e-reading devices and e-commerce such as online bookstores.
It is thus crucial for the publishing industry to start now to get ready to comply in time with the Directive. Clear information on the standards to adopt are fundamental to fulfill the technical requirements, to avoid the duplication of efforts and to start producing accessible e-books, websites and reading solutions as soon as possible.
Furthermore, for the publishing industry, the best option will be to possibly take advantage from the adoption of existing and widely used standards that have been conceived by standard organizations with accessibility as one of their main elements.
To provide all the relevant stakeholders with information on the compliance of the publishing standards with the EAA requirements we have prepared a detailed document European Accessibility Act: report on the state of the art of publishing standards. It had been published as open position by Federation of European Publishers (FEP), to foster the adoption by the EU Commission of these industry standards as technical specifications fulfilling the requirements of the EAA.
The report has been done with the collaboration of relevant stakeholders, in particular FEP (Federation of European Publishers, representing more than 29 EU Publishers’ Associations) and the W3C Accessibility task force in the EPUB 3 Working Group, responsible of setting the accessibility requirements for the EPUB standard. The report describes in detail the compliance of these standards with the requirements already available in the EAA. It also describes the accessibility requirements defined in Annex I, II and V of the EAA and with the rules set by EU Commission for the adoption of Technical specification vs EU Harmonized standards. The full document will be published with an open position paper by FEP. This article provides a summary of the most relevant highlights.
As one of the main goals of the Directive is to eliminate and prevent barriers resulting from divergent accessibility requirements in member states, the choices that will be made by the Commission in the next months to define the mandatory standard requirements to comply with are fundamental.
The Directive in fact provides for both products and services:
In the EAA, high level requirements are already described in Annex I, II and V. The Directive provides the minimum requirements that must be met but the does not detail how to comply with them.
The EU Commission can now follow two different approaches to define more detailed mandatory requirements:
In the EAA all the actors of the publishing are involved: publishers should produce their digital publications in an accessible format and the entire supply chain (retailers, e-commerce sites, hardware and software reading solutions, online platforms, DRM solutions, etc.) should make content available to users through accessible services, by clearly communicating accessibility features so that any user can use them in autonomy.
It is thus relevant for them to know the requirements they need to comply, in particular in terms of:
Currently, in the publishing industry there are standards, such as EPUB for the production of e-books as well as ONIX and Schema.org for metadata, which are already widely adopted by all the stakeholders of the supply chain worldwide. Those standards allow also the production and distribution of accessible publications.
Regarding websites, apps, and e-commerce are already adopting W3C standards that are in line with the accessibility requirements of the EAA and with the already existing EU Harmonized Standard EN 301 549 V2.1.2 (2018-08).
It would therefore be important for the Commission to consider the adoption of these standards for the EAA as for e-book and metadata as technical specifications, instead of issuing a mandate for an EU Harmonized Standard, and to refer to the already existing EU Harmonized Standard for web site, app and e-commerce.
We will provide a detailed analysis on this topic later in the document; in the meantime, we can already anticipate some good news: the EPUB format (with the support of ONIX and Schema.org) is in line with the requirements of the European Accessibility Act.
In the publishing world EPUB is in fact nowadays the most used format at international level by trade publishers to create e-books and to distribute them through the value chain and it is accepted by all aggregators and distributors. In addition, the EPUB3 format is particularly accessible because it is based on the Open Web Platform. That is the set of technologies used to create websites (including HTML, CSS, XML), and incorporates all the features of accessibility, thanks to the active collaboration to the drafting of specifications of the DAISY Consortium – an organization specialized in accessibility of digital publishing content.
The EPUB format includes all the features needed for a person with a print disability. At the same time, it can also be useful for people with other disabilities, in line with the EAA requirements of Annex I, and for the general public. Its interoperability allows it to be supported by both consumer reading devices and equipment dedicated to people with disabilities. In addition, e-books in EPUB format can be automatically voiced, transcribed into electronic braille, the characters can be enlarged and modulated in their presentation. It also allows for complete graphical customization of content, according to user needs, and can leverage advanced semantic tags (ARIA roles, etc.) for the benefit of blind readers.
In order to outline how to make EPUBs fully accessible, the EPUB Accessibility guidelines were drafted to address two key needs in the EPUB ecosystem:
The mapping work done in collaboration with the EPUB Working Group allowed us to check that every requirement of the EAA related to e-book production was supported by EPUB Accessibility 1.1. The full support of all accessibility requirements allows us to state that the EPUB format is fully compliant with the Directive.
EPUB Accessibility 1.1 defines two levels of accessibility (A, AA). The work of comparison has allowed us to identify that in order to make an EPUB compliant with EAA, it is not enough to reach the single A level, as some requirements of the double A level are necessary (for example regarding text resizing and adequate color contrast).
It is also worth mentioning that some European players, as Fondazione LIA in Italy with its catalogue of over 28.000 accessible EPUBs, and Hachette Livre that has modified its digital publishing workflow to create accessible EPUBs, prove that this standard already allows to achieve great accessibility results, as required by the Directive.
As for MOBI, the format used by Amazon, it is worth noticing that the company that used to ingest e-books as EPUBs and distributed them in its proprietary format, has recently announced to the publishing industry that, as of June 28, 2021, it will no longer ingest from publishers their own e-books files format (MOBI, PRC, AZK) for reflowable e-books, recommending providing the EPUB format instead.
As for PDFs, the format is widely used for digital publication, especially in the academic and professional publishing sector. Publications in this format can be produced with tags and therefore be accessible to blind people; in some cases, they may be difficult to use for persons who have low vision.
Furthermore, as required by the Directive, it is crucial to provide readers with detailed information describing the accessibility characteristics of each title so that any user can understand whether the content is appropriate for his/her needs before purchasing, downloading, or borrowing it. Therefore, the adoption of metadata standards for accessibility becomes absolutely relevant.
Two different metadata standards can describe accessibility characteristics and, as requested by the EAA can be distributed along the publishing value chain:
Both these metadata standards are thus fully compliant with the requirements of the European Accessibility Act.
The European Commission may decide to adopt acts establishing technical specifications if the technical specifications fulfill, as expressed in Annex II of Regulation (EU) No 1025/2012, the Requirements For The Identification Of Ict Technical Specifications and comply with Article 15.3 (a) no reference to harmonised standards is published in the Official Journal of the European Union in accordance with Regulation (EU) No 1025/2012.
All the publishing standard above described fulfill these requirements as they were developed by non-for-profit organizations (World Wide Web Consortium – the body that defines the EPUB and the Schema.org standards – and EDItEUR – the body that defines the ONIX for Books standard) on the basis of open decision-making process accessible to all interested parties in the market or markets affected by those technical specifications. Furthermore, the decision-making process was collaborative, consensus and transparency-based and did not favor any particular stakeholder. Both institutions are robust, which also ensures that standards are maintained over the long term.
The report aims at providing all the interested stakeholders with a clear overview of the state of the art of publishing standards in relationship with the EAA requirements to make informed choices. The full version of European Accessibility Act: report on the state of the art of publishing standards can be downloaded here.
The Directive is currently being adopted into national legislations and will be applicable from 28th June 2025: from then on, all the defined products and services sold to citizens have to be accessible (excluding microenterprises and some complex publication types).
 EPUB 3 is now maintained within the World Wide Web Consortium (W3C), after IDPF merging in 2017, becoming part of the greatest non-for-profit organisation for Web standards as «Publishing@W3C».
 The ONIX family of standards is developed by EDItEUR (editeur.org), an international non-for-profit organisation that includes all actors of the book supply-chain. It was created with the aim to have a shared set of metadata standards to support machine-to-machine communication in the publishing supply chain, and it is nowadays the international standard adopted in the market. The XML-based standard metadata schema for representing and communicating book industry product information in electronic form is ONIX for Books. The first version 1.0 was published in 2000, followed by version 2.1 in 2003, widely adopted in the print books sector; in 2009, to respond to the emerging requirements of the e-book market and to new business models, version 3.0 was published.