Tens of thousands of workers have been banned from using social networking sites such as Facebook by employers seeking to curb the wasting of office time. IT experts say that companies are asking for help in blocking access to Facebook, MySpace and Bebo after realising that they could not prevent their staff from surfing the sites in work hours.

In the past six months alone, Facebook’s British audience has grown at 19 times the rate of MySpace’s, surging 523 per cent to 3.2 million. MySpace, owned by News Corporation, the parent company of The Times, has 6.5 million members and Bebo has 4 million in Britain.

Graham Cluley, senior technology consultant at Sophos, a leading IT security company, said: “Websites like Facebook, Bebo and MySpace fall into the category of websites which can easily gobble up hours of worktime and distract from the employees’ real duties. Facebook is a procrastinator’s paradise.

“Groups have even sprung up on Facebook which collect people who openly admit that they are browsing the social network rather than work. The ‘I have dossed around on Facebook all day and consequently have done no work’ group has more than 240 members. In the last two months we have seen Facebook mentioned much more often, presumably as its user population explodes, by customers to us, with an interest in whether we can control users’ access to it.”

Facebook attracts an older, more class-conscious audience than MySpace and Bebo. Its members are more likely to be rich, better educated and have more prestigious jobs, according to Nielsen NetRatings. Half of Facebook’s British members are university-educated and, in comparison with the other sites, it has a higher share of professionals and executives.

A recent study found that Facebook’s British members spend an average of 143 minutes a month on the site checking on their friends, looking up former partners and updating their profile. However, some people argue that Facebook is a valuable tool that they use to stay in touch with colleagues and business associates.

Some American and Canadian companies have already banned access to Facebook. Two months ago government employees in Ontario were told that the social network was off limits.

In Britain, the Metropolitan Police, Lloyds TSB and British Gas all have internet filters preventing sites such as Facebook from being viewed at work. A spokeswoman for Scotland Yard said: “Access to some websites is blocked as there is no business need for employees to visit them. Facebook is one of these sites. Access to blocked sites is granted when required for business needs only.”

Mark Murtagh, product director at Websense, an internet security company, said: “We recently conducted research and found that in the UK around a quarter of workers admitted to being addicted or incapable of living without using social networking sites at work. These sites become to a degree a form of personal entertainment system in the office.

“Companies are thus increasingly using technological systems to filter the sites visited by their employees, partly as a security measure but also out of concern that employees are wasting a lot of time, money and bandwidth.”

Employment lawyers are warning office staff to beware of storing up trouble. Philip Bartlett, employment partner at Simmons & Simmons, said: “Employees will have been told that, at work, the internet is a business tool. There is an expectation of some personal use as there is with phone calls, but there’s a limit. Most companies have internet policies which outline acceptable personal use. It would be pretty gung-ho to go around sacking people who spend a couple of hours on Facebook. You would expect an informal chat or some disciplinary process. If these sites were continually used for personal reasons, legally, yes, it could be a sackable offence.”

How to beat the networking ban

— Simple web filtering can be circumvented by Facebook fans

— Even if the Facebook URL has been blocked all you need to do is visit Google

— Type www.facebook.com into Google’s “Translate a Web Page” facility

— You will then have complete access to Facebook, craftily disguised by Google’s URL

— Warning: robust web-filtering software may catch you out

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