Article R4451-22 of the French Labour Code
The employer shall identify any zone where workers are likely to be exposed to levels of ionising radiation exceeding: 1° For the whole body, assessed on the basis of the effective dose: 0.08 millisieverts per month; 2° For the extremities or the skin, assessed on the basis of the equivalent dose: 4 millisieverts per month; 3° For the concentration of radon activity in the air, assessed on the basis of…