Mountain climbing after diving

[CraigDiver]

Thought about climbing first and diving after?.

I have a permit to climb to the summit which is only for a certain day and time slot, but I think you are right, the safest bet would be do the mountain first then fit diving into the remaining few days of the holiday (but not the day before I fly!)

Thanks

 

[LouieLouie]

The problem with flying is the rapid ascent, just as a rapid ascent is likely to get you bent in water. When you ascend a mountain you'll offgass quicker than you climb so I wouldn't worry one bit. Cabin pressure is equal to 2700m in most commercial aircrafts and pressure will drop to that level in a matter of minutes. It will take you hours to climb to such an altitude.

 

[CraigDiver]

The problem with flying is the rapid ascent, just as a rapid ascent is likely to get you bent in water. When you ascend a mountain you'll offgass quicker than you climb so I wouldn't worry one bit. Cabin pressure is equal to 2700m in most commercial aircrafts and pressure will drop to that level in a matter of minutes. It will take you hours to climb to such an altitude.

Will be cheating and going most of the way by cable car which ascends 2482m at 8m/s - pretty rapid - cable car website here

 

[DevonDiver]

The problem with flying is the rapid ascent, just as a rapid ascent is likely to get you bent in water. When you ascend a mountain you'll offgass quicker than you climb so I wouldn't worry one bit. Cabin pressure is equal to 2700m in most commercial aircrafts and pressure will drop to that level in a matter of minutes. It will take you hours to climb to such an altitude.

It depends on the tissue saturation. As someone has mentioned already - fast tissue vs slow tissue, resulting from the dive profile/s.

If the ascent pressure gradient exceeds that saturation, then you can be in trouble. Your offgassing is dependant on the type of tissue compartment that is saturated.

Given that the majority of the ascent will be via car and cable car... and only the final 200m by foot... that's still a relatively fast ascent. Certainly fast enough to cause major concern if slow tissues were saturated.

So... there is cause to worry.

 

[CraigDiver]

It depends on the tissue saturation. As someone has mentioned already - fast tissue vs slow tissue, resulting from the dive profile/s.

If the ascent pressure gradient exceeds that saturation, then you can be in trouble. Your offgassing is dependant on the type of tissue compartment that is saturated.

Given that the majority of the ascent will be via car and cable car... and only the final 200m by foot... that's still a relatively fast ascent. Certainly fast enough to cause major concern if slow tissues were saturated.

So... there is cause to worry.

Thank you all for the excellent advice, I have decided not to dive in the couple of days before the ascent up the mountain to err on the safe side. :cool2:

 

[Phil_C]

I might be missing the obvious here but surely the risk of climbing after diving is solely down to the residual nitrogen in the body coming out as bubbles due to the lower partial pressures at greater altitude. Once your residual nitrogen levels have returned to normal after the dive then you are at no greater risk than anyone else by ascending to 12,000 foot.

My understanding was that after short shallow receational dives your nitrogen loading will have returned to normal within a fairly short period of time about 6-12 hours*, hence the no fly recomendation being set at 12 hours to be on the safe side, if so after 24 hours of no diving there would no increased risk at all.

Obviously deep or long dives which fully saturate the compartments will take longer to completely return to normal nitrogen loading but I don't see that happening here. I would have thought that if you are reasonably fit, so there are no medical issues affecting your nitrogen absorbtion and release rates then 24 hours no diving would be more than enough.

*Is this recomendation actually based on research that says nitrogen levels have returned to normal, or just that it has returned to a safe level to ascend to this altitude - the two things would be very different.

Just off to search the DAN archives and research papers !

Regards Phil

 

[CraigDiver]

My understanding was that after short shallow receational dives your nitrogen loading will have returned to normal within a fairly short period of time about 6-12 hours*, hence the no fly recomendation being set at 12 hours to be on the safe side, if so after 24 hours of no diving there would no increased risk at all.

Thanks for the input Phil but as stated earlier, flying only takes yo to a cabin pressure around 6000ft, i'll be ascending quickly over double that and you have to factor in the lack of oxygen at that altitude = lots of unknowns!