Email and internet abuse are now the number one reason for disciplinary action in UK companies according to a survey carried out by London law firm KLegal and Personnel Today magazine.

Over the past 12 months, the number of disciplinary cases for online abuse — 358 in total — exceeded the 326 cases for dishonesty, violence and health and safety breaches put together, KLegal said.

These findings back up an earlier survey of 500 HR professionals by Websense, which found that a quarter had dismissed staff for online misconduct.

These problems will keep occurring unless companies are firm about their policies, KLegal Partner Stephen Levinson explained.

"My view is that people will keep using the internet at work, because it's there, like Everest," he says.

Of the 358 cases brought, 69 people were disciplined for excessive amounts of time using the internet or email for personal use, and five of those were dismissed. Pornographic email caused 64 people to be disciplined and 25 to be dismissed. Porn sites were responsible for 53 cases and nine dismissals. Sending email that could damage a company's reputation brought 49 cases and two dismissals.

Many people use the internet at home for trawling porn sites, and then bring those personal habits to work, Levinson said. "So long as they can, they will, because people are foolish. But if you have software that can prevent them doing so, you solve the problem," he said.

Any software designer who can develop blocking software that really works, without blocking simply by skin tone or specific wording, will make a fortune, Levinson said.

It's not easy to do, however. "If the software can detect that there's a certain amount of naked flesh from the tones on the screen, it also blocks lingerie sites. Recently I sent an email that referred to 'teaching your grandmother to suck eggs', and that was rejected because of 'suck'. If we can get around those problems, we would solve the big problem," he said.

"In the meantime, you have to tell people the policies. I think many companies do tell their employees there's a policy but they're very quiet about it. You have to make enough noise and let people know they're being watched. Spell out what's acceptable, what's seen as an offensive joke; if you want to be tough, you have to be very specific," Levinson said.