Sub-paragraph 1: Principles

With the exception of the breath-holding interventions mentioned in Article R. 4461-42, interventions and work in hyperbaric environments are performed while breathing air, another gas mixture or pure oxygen under the conditions set out in this sub-section.

The employer determines the most appropriate breathing gas for the working conditions.

Breathing compressed air is permitted up to a relative pressure of 6,000 hectopascals. Above 6,000 hectopascals, specific breathing mixtures must be used.