As British Telecom revealed that it had sacked 200 employees since launching a campaign to stamp out internet misuse in the workplace, experts have advised firms to update their usage policies to ensure they cover contract staff and the latest technology.

BT's dismissals occurred over the past 18 months, since the firm first started looking into the issue of internet misuse in the workplace, a BT spokesman said. "Ten of the employees have since been reported to the police, while none has appealed against their dismissal so far," he added.

BT has filtering systems in place to monitor for certain keywords at the desktop and through remote access systems. "We also have a strong policy in place, which was very well communicated to all employees," said the BT spokesman.

A follow-up email was sent to all employees warning them that some people had been spotted breaking the policy and could face dismissal, so BT was surprised that a few staff continued to break the rules, he added. "But with the emails sent around, and people dismissed and reported to the police, we are now seeing a significant reduction in this activity."

BT was right to take action against staff visiting inappropriate sites, as it put the firm at clear risk of litigation, said Nathan Millard, legal expert at policy management specialist PolicyMatter. "But it's rare to see a large blue-chip coming out and saying it's not going to tolerate the problem from a board level, and not simply devolving it to the HR or IT department," he added.

Millard added that the release of the Information Commission's guidelines for employee monitoring, along with the BT dismissals, should encourage companies to review their internet usage policies. "And for firms offering 3G phones to workers, they might want to update their acceptable usage policies to cover these devices, as the video feature could be used to circulate inappropriate content," he added.

BT is not the only company taking a tough stance. According to a recent survey of 1,100 US firms by email filtering specialist Clearswift, almost a quarter had sacked an employee for failing to comply with email usage policies.

But the survey indicated that many companies are still not tackling the problem. Over a third did not monitor at all, and 13 percent of respondents were unsure whether their companies monitored staff.

Clearswift's product marketing manager, Jonathan Tait, believed that survey results would be similar in the UK. He said that firms should tell permanent and temporary staff of the reasons for monitoring and the potential repercussions if they break the rules. "Contractors are a big problem in terms of security," he added.

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