The Disability Rights Commission (DRC) is to begin the UK's first formal investigation into the design and technical barriers that make many websites inaccessible to people with disabilities.

This will give the DRC and other similar organisations a clearer picture of the scale of the problem and help them develop guidelines for companies and web designers.

Although the internet has the potential to offer huge benefits to disabled people, many websites fall foul of the UK Disability Discrimination Act. According to charity AbilityNet, 90 per cent of sites pose access problems.

No cases have been brought against companies in the UK but in other countries, including the US and Australia, there have been successful cases brought by people with disablities.

But the DRC would rather avoid legal confrontation and use its investigation findings to highlight problems to web designers and companies, according to its commissioner Michael Burton.

"The investigation will give us a measure of the scale of the problems. All we have at the moment is a lot of anecdotal evidence," he told vnunet.com.

"It could be failings in the current guidelines, the way they are interpreted, or lack of knowledge. We aim to register the problems on people's radars."

The investigation will be carried out in two phases. This will involve the automatic testing of 1,000 websites, spanning both the public and private sectors, to ascertain basic compliance with current guidelines set by the World Wide Web Consortium.

In addition, 50 disabled people will be involved in the in-depth testing for practical usability of a representative sample of these sites. This work will help clarify the relationship between a site's compliance with standards and its practical usability.

The results will then be analysed in collaboration with a team from the Centre for Human Computer Interaction Design at City University in London. The findings of the DRC's investigation are expected by the end of 2003.