The capture and ventilation installations are designed in such a way that concentrations in the atmosphere are not dangerous at any point for the health and safety of workers and remain below the exposure limit values set in Article R. 4412-149.
When the concentration limits mentioned in Article R. 4222-10 cannot be complied with at any point in a specific pollution room, the employer shall implement the organisational measures necessary to ensure that workers’ exposure does not exceed these limits on average over an eight-hour period.
Air intake devices compensating for the volumes extracted shall be designed and arranged in such a way as not to reduce the effectiveness of the capture systems.
An automatic warning device signals any failure of the capture systems which is not directly detectable by the occupants of the premises.