A new French law establishing workers’ “right to disconnect” goes into effect today. The law requires companies with more than 50 employees to establish hours when staff should not send or answer emails. The goals of the law include making sure employees are fairly paid for work, and preventing burnout by protecting private time.

French legislator Benoit Hamon, speaking to the BBC, described the law as an answer to the travails of employees who “leave the office, but they do not leave their work. They remain attached by a kind of electronic leash—like a dog.”

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While the measure may seem like a boon to workers, it was reportedly the most broadly supported measure of a comprehensive labor package passed in May. The package as a whole was primarily oriented to liberalizing France’s job market, including by making it easier to fire workers, and sparked widespread protests.

The email restrictions could provide a benefit to both workers and businesses, by making employees more relaxed and effective. As NPR points out, academic studies have found that workplace email is a significant source of stress. A group of Stanford business professors have estimated that workplace stress added between $125 and $190 billion dollars per year to America’s healthcare costs, amounting to between 5 and 8% of total costs. Overwork accounted for $48 billion of that.

Those healthcare costs are largely borne by employers, along with the drag of irritable or absent employees worn down by the colonization of their private lives.

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Recognizing this, major European corporations have made attempts on their own to reduce the risks of burnout and overwork for employees. In 2012, Volkswagen blocked all emails to employees’ Blackberries after-hours. Daimler took the step of deleting all emails received by employees while on vacation.

The German labor ministry enacted an only slightly less sweeping ban in 2014, prohibiting managers from calling or emailing staff after work hours, except in an emergency.