Key Differences Between WCAG1.0 and WCAG2.0

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Over the years the internet (and how we interact with it) have changed in fundamental ways. Innovation has brought us video or audio embedded in pages, web access on smartphones, AJAX (the new DHTML) amongst other things.

Whilst innovation is good and can make the world and the web a better place, many of these innovations cause even more and newer problems for users with disabilities. It’s as if those who rely on assistive technology are for ever having to play catchup which is not great if the new version of your screen reader costs $700.

Accessibility guidelines

W3C Web Accessibility Initiative LogoThe World Wide Web Consortium (W3C) published the first version of their web content accessibility guidelines (WCAG1.0) in 1999 and the guidelines reflected the state of the web in the late 90s.

The updated version of the guidelines (WCAG2.0) became a recommendation on 11the December 2008 – just over a year ago as I write this. I was not directly involved with their creation but I watched from the sidelines and know enough to realise that a replacement for the first version (WCAG1.0) was well overdue. Those original guidelines were so dated. Best practices had also changed, and some key techniques in WCAG2.0 were not even mentioned in WCAG1.0.

Has anyone noticed?

Given the year that has elapsed since the adoption of WCAG2.0 I’m surprised that so many sites and businesses seem either unaware of WCAG2.0 or reluctant to migrate.

I expect that every web developer like me who understands accessibility and takes it into account when building websites has some issues with WCAG2.0. However I do believe that overall WCAG2.0 gets the balance about right.

So what are the key differences?

Compliance levels have a similar structure between the two sets of guidelines. The priority 1 (A), 2 (AA) or 3 (AAA) of WCAG1.0 is effectively the same as A, AA, and AAA of WCAG2.0.

There are three groups of differences between the WCAG1.0 and WCAG2.0 guidelines. This section covers the significant ones (and is not exhaustive)

New to WCAG2.0

  • Instructions on how to understand or operate content should not rely on shape or sound only.
  • Applets or other components (Flash etc) should not trap the cursor when user is using keyboard to move around page.
  • All pages should have titles that describe what the page features.
  • Headings and labels should describe topic or purpose.
  • Keyboard focus should always be visible.
  • Input errors must be described to the user in text, and valid value clues given to the user where possible.

WCAG1.0 guidelines not within WCAG2.0

Because of evolving best practices or browser/assistive technology functionality, some WCAG1.0 guidelines are not contained within WCAG2.0:

  • Providing extra text links for client-side image maps – browsers now all support alt attributes on image maps
  • Providing keyboard shortcuts or accesskeys – no longer deemed essential. In fact accesskeys can interfere with assistive technology keystrokes so extreme care should be taken if they are used.
  • Positioning of implicit labels for input controls – explicit linking of controls and labels is still required but positioning can vary
  • Use of default text inside form controls – this is no longer required
  • Pages should function if scripting switched off – no longer specifically required, but dynamic content must be accessible in WCAG2.0

Difference in emphasis between WCAG1.0 and WCAG2.0

The newer emphasis of WCAG2.0 an cause issues for sites that previously met WCAG1.0 guidelines to a certain level

  • Creating pages that contain valid HTML etc – was Priority 2 now Level A
  • Use of properly nested headings within pages- was Priority 2 now Level A
  • Mark up lists as list items – was Priority 2 now Level A
  • Markup quotations – was Priority 2 now Level A
  • Identify primary language of page – was Priority 3 now Level A
  • Identify changes in language within page – was Priority 1 now Level AA
  • Don’t use table headers just to make text bold – was Priority 2 now Level A
  • All functionality must be accessible via keyboard – was Priority 2 now Level A
  • Allow users to stop items blinking, stop movement, auto-refreshing  and auto-redirect in pages – was Priority 2 now Level A
  • Scripted elements, applets and other dynamic elements must be accessible – was Priority 2 now Level A
  • Pages must have a logical tab order – was Priority 3 now Level A
  • Don’t open new windows without warning user – was Priority 2 now Level A
  • Explicitly link input fields with their labels – was Priority 2 now Level A
  • Make the destination of every link clear – was Priority 2 now Level A
  • Provide bypass or skip links – was Priority 3 now Level A

See the W3C WAI (Web Accessibility Initiative) offical WCAG1.0 to WCAG2.0 differences.

And what does that mean for businesses?

This affects businesses who have stated their compliance level for their website. With the new WCAG2.0 guidelines and the re-emphasis of other guidelines it cannot be denied that to achieve level AA for your site in WCAG2.0 is a greater ask than the corresponding level in WCAG1.0.

That said, the WCAG2.0 guidelines reflect a more contemporary state of the web than the much older WCAG1.0 so a site which does meet level AA in WCAG2.0 is providing a significant level of accessibility and should be usable by the vast majority of users.

Got something to say?

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