Article D4153-34 of the French Labour Code
I. – It is forbidden to assign young people : 1° inspecting, maintaining and cleaning the inside of tanks, cisterns, basins and reservoirs ; 2° Work involving operations in a confined environment, in particular in wells, gas pipes, flues, sewers, pits and galleries. II. – The prohibition mentioned in I may be waived under the conditions and in the forms set out in section 3 of this chapter.