Nahles told the Rheinische Post newspaper that she had commissioned the Federal Institute for Health and Safety at Work to come up with a report on the feasibility of a possible law to protect workers from stress caused by smartphones and constant contact with their bosses.

“There is an undeniable link between having to be constantly available [for work] and the rise in mental illnesses,” she said.

But she added it would be a challenge to implement any law.

Guntram Schneider, Labour Minister for Germany’s most populous state, North Rhine-Westphalia, called for an anti-stress law at the start of August. He envisaged a law banning employers from contacting employees at certain times of the day.

According to the Association of German Pension Providers, 66,441 workers were on disability pensions last year because of mental illnesses, including depression. The number has risen by almost 20,000 since 2005.

A high number of sick days are also caused by stress and mental illness according to health insurers.

Health insurer Techniker Krankenkasse (TK) found in a report last year that stress levels had increased in the last 12 months for 53 percent of respondents to their survey.

And in August last year, television channel Das Erste aired a show called “Stressed Germany” investigating the country's problem. The programme revealed that the number of sick days taken as a result of mental illnesses had risen by 80 percent in the last 15 years. 

Germany’s coalition government wrote in their coalition agreement last year that they would improve the “work-life balance” of workers, but no laws apply to when bosses can contact their employees.

Jan Jurczyk from Verdi, one of Germany’s biggest unions, told The Local at the start of August that they would like to see more companies introduce guidelines on emailing and contacting workers out of office hours, describing it as a “grey area” legally, although he stopped short of calling for legislation to be introduced.

“The very high productivity of German workers is dependent on having downtime,” he said. “It is not in companies' interests for their employees to be overburdened.”

German companies including Volkswagen and Deutsche Telekom have guidelines on contacting employees out of office hours, as does Germany’s Labour Ministry.

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