Just over 25 per cent of the global online workforce, or 27 million employees, have their internet or email use monitored by their employers.
Worldwide sales of staff-monitoring software are projected to be $140m in 2001, or about $5.25 per monitored employee per year, according to a study by the Privacy Foundation. The low cost of such software is one reason why its use is becoming more prevalent.
The study also questioned whether employers were giving staff sufficient notice of their continuous web and email monitoring.
"Notice alone might not go far enough," said Andrew Schulman, chief researcher for the Privacy Foundation's Workplace Surveillance Project and author of the study. "Companies and government agencies are basing firing and suspension decisions on the employee-monitoring reports."
Schulman pointed out that employees are generally not told beforehand what information will be gathered and how it will be judged. "Companies can use employee-monitoring logs as a kind of 'wishing well' to justify actions against employees, including dismissals and layoffs," he said.
"While employers may fear that putting such knowledge in the hands of employees may allow them to circumvent these systems, the practice of keeping employees uninformed about the details of monitoring may be tantamount to entrapment," he added.
In the past, employers have cited productivity concerns and liability for sexual harassment or other employee misbehaviour as reasons for monitoring internet use.
But the Privacy Foundation's research indicates that low cost technology, more than any other factor, is driving the growth of email and web surveillance in the workplace.
Websense is the most frequently used web monitoring product and MIMEsweeper is the most popular email product, the study found.
Major companies that monitor employees' online activities include Glaxo Wellcome, Nike, Duracell and American Express.
Furthermore, the study found that workplace monitoring is growing fast, and that the number of employees being watched has nearly doubled annually over the last few years.
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