You know, Bert, the API's Recommended Practice #755 covering Fatigue Risk Management for Personnel in the Refining and Petrochemical Industries -- that came out following the BP Texas City disaster -- states that for workers on 12-hour shifts under Normal Operations -- "Work sets shall not exceed 7 consecutive day or night shifts". For Outages, "Work sets shall not exceed 14 consecutive day or night shifts".
"For any exceptions to these mandatory requirements, an established management exception process shall be initiated. The exception process shall involve the employee's immediate supervisor and one other management representative. The process shall include a documented risk assessment and mitigation plan."
I'm just looking out for your well being, buddy! Of course, this comes from the AMERICAN Petroleum Institute... and you work for a French company!