Quote: (Originally Posted by Marc T)
using the same "computation", you can see that using heliox on deco ( ethen after a trimix dive ) is safe in any case.
Thta's my opinion, and a heliox for bail out is a good solution in most cases but not sure its true
Yes maybe, but I think those computations are a littel too simple. Not taking into consideration transient events and several linked compartments.
The thing I think can be dangerous with a switch to a much higher pHe is that it will go in som much faster than the N2 is going out.
Found an old article:
Prlonged bubble production by transient isobaric counter-equilibration of helium against nitrogen.
Its about animals subjected to saturation at 132 and 198 ft on N2 (PO2 0.3)
followed by a sudden isobaric gas switch from saturation on N2 to He.
Bubbles occurred.
The final sentence of the abstract:
"Gas switches from a more soluble to a less soluble and/or more rapidly diffusing gas should therefore be avoided until physiological limits are well worked out."
The abstract of the article:
http://www.ncbi.nlm.nih.gov/entrez/q...=pubmed_docsum
Sorry if this is considered off topic in this thread...