100m air dive & workup, PG

[Tortuga68]

My thoughts are that unless you're predisposed or a commercial/saturation diver, you're probably not at high risk of DON

Some of the studies I've seen of commercial shellfish divers seem to have been impacted by poor diving practices, experience of DCS and lack of treatment (recompression) which I believe is why you see such high probabilities of DON for these people

Some studies of Navy divers have shown much lower rates (2%)

Here's the Rubicon archive: Rubicon Research Repository: Search Results

 

[lowviz]

My thoughts are that unless you're predisposed or a commercial/saturation diver, you're probably not at high risk of DON................

Thanks for your reply.

The obvious implication was, for your type of diving, can one avoid DON or will it catch up with you? The fact that you did not report a personal case of DON is most comforting. However, I'll still be stretching out those shallow stops...

Best,
lowviz

 

[jtivat]

Thanks for your reply.

The obvious implication was, for your type of diving, can one avoid DON or will it catch up with you? The fact that you did not report a personal case of DON is most comforting. However, I'll still be stretching out those shallow stops...

Best,
lowviz

Just curious what this thread has to do with DON? Have you read anything that would suggest diving Deep Air would put you at a higher risk?

Not being smart this is a real question as I don't know a lot about DON.

Thanks

 

[lowviz]

Just curious what this thread has to do with DON? Have you read anything that would suggest diving Deep Air would put you at a higher risk?....................

Shellfish divers (air) share the same risk of DON as deeper mixed-gas divers. Can't find anything specific with regard to gas, but gets me to wondering about slow compartments and lots of nitrogen. I would like to think that it is just poor diving practices.

-Tortuga68 is one of the few deep air divers that will freely answer questions. I'd like to use air down to 1.6, -would also like to know in advance if there are concerns other than the obvious one of narcosis.

 

[jtivat]

Shellfish divers (air) share the same risk of DON as deeper mixed-gas divers. Can't find anything specific with regard to gas, but gets me to wondering about slow compartments and lots of nitrogen. I would like to think that it is just poor diving practices.

-Tortuga68 is one of the few deep air divers that will freely answer questions. I'd like to use air down to 1.6, -would also like to know in advance if there are concerns other than the obvious one of narcosis.

Got ya thanks!

I did a little reading and found some articles stated Nitrogen directly and some sounded more like any gas changing pressure.

But this is a subject I have not heard much on if anything at least around the Great Lakes Tech divers.

 

[lowviz]

Got ya thanks!

I did a little reading and found some articles stated Nitrogen directly and some sounded more like any gas changing pressure.

But this is a subject I have not heard much on if anything at least around the Great Lakes Tech divers.

Start a thread if you find anything interesting, I'll do the same.

 

[rjack321]

My question concerns Type IV DCS (dysbaric osteonecrosis). Since I'm venturing deeper into the tech world, this is something that I often wonder about. My concern stems from the uncomfortably high incidence in commercial, military, and shellfish divers.

They all dive cheap high N2 mixes, essentially skip deep stops since they aren't part of Navy type tables and protocols, and do lots of shallow Buhlmann-esque or even chamber deco. They also do alot more dives/per day and per yr than most recreational deco dives.

 

[lowviz]

They all dive cheap high N2 mixes, essentially skip deep stops since they aren't part of Navy type tables and protocols, and do lots of shallow Buhlmann-esque or even chamber deco. They also do alot more dives/per day and per yr than most recreational deco dives.

Diving Doctor - Diver Magazine September 1998 I'm not ready to dismiss it just yet.

Quoted from the link above:
In 1931 the HMS Poseidon, a Royal Navy submarine, had an accident and five men were trapped at 38 meters (120 ft) sea water pressure for two to three hours before they escaped to the surface. All five developed DCS soon after surfacing. Twelve years later, when three of the five had x-rays taken, all three had DON, one with partial collapse of both femoral heads. None of the five were divers or had other known pressure exposures. Therefore we know that DON can develop from a single exposure to pressure.

I am aware that the Poseidon incident was three hours at 120 ft, but I'm curious about possible cumulative effects. It is documented that DON jumps significantly in older divers. -thus my interest.

 

[jtivat]

Diving Doctor - Diver Magazine September 1998 I'm not ready to dismiss it just yet.

Quoted from the link above:
In 1931 the HMS Poseidon, a Royal Navy submarine, had an accident and five men were trapped at 38 meters (120 ft) sea water pressure for two to three hours before they escaped to the surface. All five developed DCS soon after surfacing. Twelve years later, when three of the five had x-rays taken, all three had DON, one with partial collapse of both femoral heads. None of the five were divers or had other known pressure exposures. Therefore we know that DON can develop from a single exposure to pressure.

I am aware that the Poseidon incident was three hours at 120 ft, but I'm curious about possible cumulative effects. It is documented that DON jumps significantly in older divers. -thus my interest.

If they "escaped" I bet they did no deco.

 

[rjack321]

All five developed DCS soon after surfacing. Twelve years later, when three of the five had x-rays taken, all three had DON, one with partial collapse of both femoral heads. None of the five were divers or had other known pressure exposures. Therefore we know that DON can develop from a single exposure [-]to pressure[/-]DCS event.

I am aware that the Poseidon incident was three hours at 120 ft, but I'm curious about possible cumulative effects. It is documented that DON jumps significantly in older divers. -thus my interest.

Fixed that. Block a bunch of blood vessels with bubbles and tissue can die. Dead bone = aseptic bone necrosis.

Welcome to the great experiment that is deco diving.