One in ten UK websites are incompatible with Firefox, according to research from web testing firm SciVisum. 

The company found that three per cent of sites turn away non Internet Explorer users, and seven per cent use non-standard code recognised only by IE.

Nearly 50 million people have downloaded Firefox, making it the second most popular browser on the market. 

"When webmasters design for IE and not standards-compliant browsers they often end up restricting user access to the website, which can have detrimental effects for a company," said Deri Jones, chief executive at SciVisum.

"Surprisingly, after all these years, users of standards-compliant browsers are still faced with sites that do not support their browser or with a link suggesting that they download IE, a browser they had presumably chosen not to use."

The sites named and shamed in the report for being IE only include the Lloyds/TSB insurance site, the government's Job Centre web page and Odeon cinemas. 

SciVisum recommends developers to use the official Cascading Style Sheets 2 (CSS2) specification, presented by the World Wide Web Consortium. 

CSS2 is a non-browser specific technology that allows all mainstream browsers full access to sites.