EMPLOYERS in the south face legal action if they read workers' e-mails or listen in on their phone calls unannounced.

Firms will have to spell out, under a new code on workplace monitoring, when staff can and cannot use the work phone, e-mail and Internet for private communications.

The 42-page guidance code is intended to drive out 'big brother' snooping and strike a balance between the rights of workers and the interests of employers.

Although the long-awaited code does not impose legal burdens, firms could find themselves on the wrong end of a lawyer's wrath.

Any intrusion breaches are likely to be brought up in employment tribunals, with the prospect of a costly payout for wrongful dismissal.

The minefield issue of workplace monitoring was raised in business South earlier this month.

An employment law specialist from Hampshire warned that bosses should clearly tell staff that e-mails and Internet use will be looked at for excessive use and inappropriate content, such as pornography.

Accessing sexually explicit material on the computer is currently one of the main reasons people are sacked, along with violence and dishonesty.

The new code covers all forms of monitoring, including surveillance cameras, website access, e-mail transmission and voicemail.

"It will usually be intrusive to monitor your workers," the code states.

Employers will now have to justify any surveillance and make sure workers are aware of the reasons for that.

John Cridland, CBI deputy director-general, said: "It's crucial for business to know where monitoring ends and unwarranted intrusion begins."