NB: Also posted in the new Web Usability website.
This is a story about web page headings and sub-headings: A story that tries to look beyond the absurd distinctions that are sometimes made about the usability and accessibility of web content, to ask who needs headings and why.
Imagine, if you will, a web page containing a 5,000 word article; a large slab of text with many sentences and paragraphs. Most, if not all, people will find this article easier to read if it is broken up into sections, each identified with an appropriate heading or sub-heading, and for people with disabilities it can be especially important. This is the starting point for our discussion of web content usability and accessibility.
WCAG 2.0 – usability and accessibility
The launch of the first Mosaic browser in 1993 could be considered the beginning of the mass consumption, commercial web as we know it today. The release of the W3C Web Content Accessibility Guidelines (WCAG 1.0) six years later in 1999, highlighted the importance of making sure this fantastic new communication medium was accessible to all, as encapsulated in this oft quoted comment by W3C Director Tim Berners Lee, “The power of the web is in its universality. Access by everyone regardless of disability is an essential aspect.”
Version 2 of the Web Content Accessibility Guidelines (WCAG 2.0) was released at the end of 2008. Two guiding principles during the development of WCAG 2.0 were the need to have guidelines that could be applied to different web technologies, and the need for rules (Success Criteria) that could be reliably tested by machines and/or human evaluators with relative ease. This desire for a more accurate system of compliance testing meant that the inevitable blurring of the boundary between usability and accessibility was avoided as far as possible when framing WCAG 2.0. “There are many general usability guidelines that make content more usable by all people, including those with disabilities. However, in WCAG 2.0, we only include those guidelines that address problems particular to people with disabilities.” [Understanding the Four Principles of Accessibility]
WCAG 2.0 has three levels of conformance for Success Criteria; ‘A’, ‘AA’ or ‘AAA’, and at least all level ‘A’ success criteria must be complied with before a site can claim conformance with WCAG 2.0. Many governments and organisations concerned with the accessibility of web content now use WCAG 2.0 as the benchmark, requiring all sites under their jurisdiction to conform at a specific level, for example, the Australian Human Rights Commission advocates sites “comply with WCAG 2.0 to a minimum of AA-Level conformance”.
Unfortunately, in the push for accessibility purity by WCAG 2.0, most issues with a taint of usability were pushed into Level AAA, and even the W3C advises, “It is not recommended that Level AAA conformance be required as a general policy for entire sites because it is not possible to satisfy all Level AAA Success Criteria for some content”. [WCAG 2.0 Conformance Requirements]
(It should be noted, WCAG 2.0 Success Criteria levels are not direct equivalents to the WCAG 1.0 Priority levels.)
Headings and WCAG 2.0
When it comes to our imagined 5,000 slab of words, there are, as far as I can see, three success criteria that relate directly to use of headings and sub-headings:
1.3.1 Info and Relationships: Information, structure, and relationships conveyed through presentation can be programmatically determined or are available in text. (Level A)
2.4.6 Headings and Labels: Headings and labels describe topic or purpose. (Level AA)
2.4.10 Section Headings: Section headings are used to organize the content. (Level AAA)
The usability of a 5,000 word article for all web users is likely be improved by presenting the information in a number of sections each identified with a heading. Furthermore, the article content will be more accessible to people with a range of disabilities, including some with cognitive and/or learning difficulties as well as people who rely on screen readers to access the web. However, the basic requirement to organise web content into sections is at Level AAA, and so failing to break up our large slab of text with headings would not, in itself, result in a failure to comply with the WCAG Level A or Level AA requirements of most jurisdictions.
What happens at the other end of the compliance spectrum also appears to be interesting in an absurd sort of way. It seems to me that it is possible to comply at Level A with meaningless headings and sub-headings, so long as they use the correct HTML heading mark-up.
What! You might shriek. Well, let me explain. Say our 5,000 word article is presented in sections, each identified with generic heading text that literally uses some meaningless words like ‘heading’ or ‘sub-heading’, but marked up appropriately (i.e. <h1>heading</h1> … <h2>sub-heading</h2> etc). This would appear to comply at Level A (success criterion 1.3.1), since to quote Understanding WCAG 2.0, “The intent of this Success Criterion is to ensure that information and relationships that are implied by visual or auditory formatting are preserved when the presentation format changes.” (Understanding Success Criteria 1.3.1). Or to put it another way, the information available through presentation is also being conveyed programmatically. The screen reader user, like everyone else would know, for example, that something called ‘heading’ is a main heading at H1, and at a lower level in the hierarchy there are items called ‘sub-heading’ at H2. Clearly, headings such as these would be a kind of visual pollution and meaningless to everyone, but the requirement for headings to actually describe a topic or purpose is at Level AA.
As with Goldilocks, something in the middle seems to be just right. At Level AA, headings need to be meaningful, and since a page can’t comply at AA without complying at A, this meaningfulness needs to be programmatically determinable. Meaningful headings will be easier for everyone to understand and will help those who have problems reading to locate the information they are seeking. And for screen reader users, as we should all know by now, HTML heading elements are a vital tool, since it allows them to easily identify, locate and navigate to different sections of a web document.
Of course with our 5,000 word slab of sentences and paragraphs, this middle AA path will only apply if the site author thought to include headings at all. And if they didn’t, people with cognitive disabilities and reading difficulties are likely to be among those who will suffer the most, because meeting their specific accessibility need for meaningful headings, and several other issues, is a Level AAA concern, and so easily ignored.
Roger Hudson will consider different aspects of this issue in two presentations at the CSUN 2013 International Technology and Persons with Disabilities Conference in San Diego.
Accessibility is more than WCAG Compliance: Wednesday February 27 at 8.00 am (ouch).
The Forgotten of Web Accessibility: Wednesday February 28 at 9.20 am.