The World Wide Web Consortium (W3C) has launched a new version of its Web Content Accessibility Guidelines (WCAG) standard, making it easier to understand and test by firms wishing to comply.

WCAG 2.0 updates the standard originally published in 1999 and is organised under four principles: perceivable, operable, understandable and robust. Compliance is measured at three levels: A, AA and AAA.

"It can be applied to any technology used on the web and allows the opening up of all types of content for people with disabilities," said Judy Brewer, head of the W3C's Web Accessibility Initiative. "We expect it to become the unifying standard for web accessibility internationally."

The new version improves on WAGC 1.0 by broadening the types of technologies, sites and languages covered by the standard. It has also been developed with more international input, and can be tested via automated and human evaluation, according to Brewer.

"This enables people to know when they've met the requirements, and was one of our goals as we had strong demand for this," she added.

"There is an extensive array of materials to support developers' needs, proven design approaches on how to meet the WCAG, and a framework for developers to innovate and still meet the requirements."