While on the subject Checks what would you do if yer cockpit
oxy bottle suddenly went to '0' on the SD in cruise at F380?
You had a suck on the masks and confirmed the loss of O2.
Case 1: Plenty of nearby airports
Case 2: 120 min ETOPS - nearest airport 100 min all engines
I know what I'd do, but just asking your opinion for discussion.
Yep it happened to me! 