When Renault held a training session for its workers at its Technocentre outside Paris last year on how to spot signs of stress in the workplace, the French carmaker was hoping to address issues raised by the suicide of a 39-year-old engineer the previous autumn.

But any lessons were quickly overshadowed by the discovery the following day of another body near the training sessions. The carmaker has suffered three suicides in just over a year at its Yvelines site, two of which have been classified as industrial accidents because they happened on site.