Accessibility in PDF: Making Multimedia Documents Inclusive
Co-writer: Shrikant Patki
Introduction:
Accessibility is referred to as the implementation of providing access to opportunities and resources to the greatest possible reach, avoiding hindrances that prevent interacting with digital content and tools on the web including people with physical disabilities, circumstantial disadvantages, and socio-economic limitations in terms of internet connection and speed. The fundamental outlook behind accessibility is when contents are properly designed and developed, a greater number of people have access to information and functionality. This article is particularly focused on accessibility in PDFs.
What’s a PDF?
It is a file format of electronic documents with limited editable options. We all encounter PDF documents in our day-to-day life. Employment contracts, Insurance policies, digital books, E-invoices, professional resumes etc. extensively use PDF documents. It’s characteristic to transfer electronic data without having to consider any distortion along the way has established itself as an unavoidably useful tool in the digital world. By definition, PDF or Portable Document Format is an open standard file format developed by Adobe to exhibit read-only web-based documents consistently regardless of the application software, hardware or operating system. A PDF file comprises a complete set of a fixed-layout document which includes text, images, media, hyperlinks, interactive buttons and related information. Its universal popularity can be attributed to its advantages of graphical integrity on different platforms, the convenience of use in creating and consuming the documents, the characteristics of secure sharing and so on.
Need for accessibility:
Shyam is looking to invest in a banking policy. The Bank Marketing Representative explains the terms to him and provides a contractual document with the details of the policy. Shyam being visually impaired finds himself unable to grasp the information in that document. The Representative now arranges an accessible PDF formatted document which Shyam uses with a screen reader and thereafter moves forward to consolidate the deal on the scheme.
The above-mentioned anecdote demonstrates the inclusivity of users at disadvantage in consuming web tools as well as the extended reach of the customer base of an entity as a result of implementing accessibility practices in applications. In a broader sense, to ensure the common access of PDF files to most people, including users in unfavorable circumstances such as having cognitive limitations, screen-reader users, users with intellectual limitations etc. to understand content more readily, the document needs to be developed properly.
From the legislation perspective, the World Wide Web Consortium (W3C), the main international standards organization for the Internet has released a detailed set of Web Content Accessibility Guidelines (WCAG) in its web accessibility initiative to provide directives to maintain accessibility in web content including PDF documents. Thus, accessible PDF documents ascertain more consumer reach with enhanced user experience as well as accomplish legal compliance associated with it.
Making PDFs accessible:
Criteria to make PDFs accessible include proper formatting of documents with tagging and metadata, easily navigable structure, providing alternate formats like captions for audio and video contents, text alternatives for images or graphics, simple procedures for functionality, bookmarking, typography, contrast & colors, highlights etc. More detailed overview of making accessible documents can be described as follows:
- PDF metadata: Using backend information, assistive technologies for reading may be able to interpret the document. That metadata includes the author’s name, document title, related subject, language, keywords etc.
- Document details: The document should include the title, headers etc. along with the current chapter and section on the page, page numbers, date details etc. to assist with accessibility.
- Logical structure: Arranging the document into a hierarchical structure using headers, paragraphs, lists, footnotes, images and tabled data.
- Tagging PDF contents: Following standard semantic structure and attributes in the document to allow the document contents like text, images and other media to be consumed in relevant reading order as well as to be extracted and reused for other purposes.
- Navigation assistance: There should be relevant navigation techniques to assist the user in searching and indexing the content in the document.
- Accessible hyperlinks: Hyperlinks, URLs etc. should have distinct tagging and should convey comprehensible information about redirecting destinations.
- Alternative texts: Images must have alt-texts to serve visually challenged users, which will associate them with screen readers.
- Form descriptions: Implementing tagged form fields, tooltip information in relevant places like icons, multi-layered expressions to exhibit validations, providing labels for interactive form controls, placement rules for checkboxes, radio buttons, lists etc.
An accessible PDF document thus created, works with almost all assistive technology software, eg : screen magnifiers, screen readers, speech-recognition, text-to-speech software, Braille displays etc., and results in enhanced outreach to users.
Some Don’ts:
To improve accessibility and ensure a better user experience, the following factors should be avoided:
- Screen flicker: Avoid unnecessary animations or changing brightness levels on screen as these might affect accessibility and user-friendliness in utilizing the document.
- Timed responses: Sometimes documents require time restrictions to interact with their content. In that case, sudden closure must be avoided. Proper time-out notification must be provided before the closure to let the user complete the pending task.
- Colors & contrast: No reliance on color or sensory characteristics alone to convey meaning, use of color combinations that provide a sufficient degree of contrast, avoid using flashing or blinking elements, no focus changes without user initiation etc.
Conclusion:
The extensive usability of PDF documents necessitates that while creating content with this file format, accessibility practices must be ensured to maintain the compatibility of the information media among maximum users. A series of guidelines (WCAG 2.0) is also set in place, regulated by related forums which assist in adhering to accessibility standards. One can also make use of multiple software and online tools like Adobe Acrobat or other PDF accessibility checkers to test and verify errors, provide remediation and thus improve the multimedia document to make it more inclusive.
