Asphyxiant tunnel

In the underground iron mine of Moyeuvre-Grande, walking towards the flooded part of the mine. There's a very-very strong lack of oxygen (16,4% to 15%). It's dangerous and you can hear me walking like a galley slave, with high difficulties to breathe. We know that we have no more than 10 minuts to verify the entrance of the called Delivrance tunnel, just because of the lack of oxygen. We encountered a defeat because we would need a boat. But a boat would mean more than 20 minuts, it's impossible, death would be near. The bip you hear is the oxygen detector and the level is so dreadful that we made a shut-down on the automatical alarm - it would be shouting everytime. It was, for sure, a critical incursion in this part of the mine. Finally, it took us 12 minuts to verify the impossibility to go beyond the asphyxiant gas district. Recorded binaural in a extremely harsh period, sorry that this recording is not perfect.