Fatality off Pensacola - Read and learn

[mathauck0814]

The discussion of PP02 is immaterial in this dive. If "diver" experienced lung overexpansion on account of a breath-hold from 20 feet the mix would have nothing to do with it. Otherwise if DCS were the culprit a lower EANx mix would just have increased the amount of inert gas he onboarded in the dive.

1.4 isn't a hard line. I personally have no issue with diving to 1.4 if the working phase of a dive is not particularly hard work, but that's a personal decision and a judgement call.

[ahava]

I realize that this incident is long past, but I've been "trolling" the Accidents and Incidents" forum for things to look out for and learn from. That they were exceeding the recommended depth my first thought as well, although being a newbie I had to look it up to be sure that the recommended limit on 36%EAN is 95 ft. If they knew the bottom was @ 102, why use 36% instead of 32%?

Confused, but learning,
Kevin L

This is what is taught. But in pratice1.4pp02 is not a hard line. It is more of a recommondation. This number is very often pushed based on the particulars of the dive (time,workload,last dive, etc.etc)

[Hetland]

This is what is taught. But in pratice1.4pp02 is not a hard line. It is more of a recommondation. This number is very often pushed based on the particulars of the dive (time,workload,last dive, etc.etc)

IIRC, I was taught that 1.6 was the "absolute" limit, but prudence dictated that a 1.4 should be the practical limit. I set my alarms for 1.5 so they don't bug me when I'm close to 1.4, but I always keep a close eye on my actual ppo2, and limit either work or time in the 1.4-1.5 range.

That said, I always err on the side of lean mixes. I'd rather lose a minute of bottom time or add a minute to my safety stop, than limit my depth unnecessarily, or have a seizure

Hunting, either bugs, or spearfishing, is likely to increase your breathing rate and CO2 retention, both of which, can push you closer to ox-tox. Again, not a factor in this incident, but perhaps worth mentioning.

[halemanō]

Current "Standards" have been "lawyered" down to the lowest common denominator, which is pretty much an obese couch potato with congestive heart disease who "just barely" snorkels 300 yards.

Lets get real about MODs for a moment.


1.4 is incredibly conservative. In fact, 1.6 is rather conservative. Those are numbers pushed forward by agencies with liability concerns, physicians with liability concerns, and manufacturer's with liability concerns ... in other words, lawyers.


In the 1960s we dove to 2.0 routinely, we dove pure oxygen rebreathers to 30 feet with occasional bounces deeper, even to 60 feet and we tested our oxygen tolerance in chambers, on pure oxygen at 60 feet. There were not a whole lot of hits, all that I personally knew about were on chamber tests. So I have to admit, I am a little amused at the trepidation that diving 1.6 and decompressing at 1.8 is met with.

[Shot a man in Reno...]

There has been a lot of speculation about the dead diver and 36% nitrox.

The Sudden-buddy said that he himself had 36%. Nowhere was it stated what the dead diver was using for a diving gas. The sudden-buddy only stated that people on the boat ranged from 30-36%.

[Garth]

My take for what I would do if my buddy was out of air. Donate reg establish buoyancy, then turn dive, ascend slowly to safety stop if in NDL or first deco stop if diving beyond NDL. If it was solely an OOA then the buddy should expect to stay on deco as long as I have enough air to complete the stop, ascend to surface and inflate my wing when we arrive on the surface. You probably didn't go OOA because of some voodoo pulmonary event, rather because you weren't monitoring your supply.
If I found myself LOA and buddy OOA then i would donate and make a slow ascent stopping only if I had enough air for myself, my buddy our ascent and some left over to inflate on the surface.
If I was performing a technical dive with deco and ran into a NDL diver out of air I would donate establish good buoyancy then tether him to the nearest NDL diver with air in their tanks if possible. If there were none then he would be sitting on my first stop with me sharing my backgas. His decision to leave.
If you have the air/gas/nitrox whatever... Why not use it. OOA shouldn't be a WTF moment if there is available gas.
That would be how I was trained. I reserve the right to dive as I see fit aside from an agency although I feel that some agencies have good general rules.
I like what the one guy said about.. Dive as though you were trained.

[Garth]

There has been a lot of speculation about the dead diver and 36% nitrox.

The Sudden-buddy said that he himself had 36%. Nowhere was it stated what the dead diver was using for a diving gas. The sudden-buddy only stated that people on the boat ranged from 30-36%.

I don't think this has anything to do with the event. He ran out of air right?

[Garth]

Ok. So now that we know ppo2 ha nothing to do with this ... Moving on to something else...

[RonFrank]

Something happened to this diver, but what?

DIVER seemed semi responsive for about the first 20 minutes, slowly gasping for breath and occasionally slowly moving an arm; he did not blink and his pupils were dilated and eyes half shut. He remained purple with veins showing in his cheek and neck. His face was very swelled. I noted gurgling in his lungs as I gave breaths.

I can find nothing that matches these symptoms, Pulmonary Immersion Edema? (shades of DeniseGG)? Jax had this question, but you all want to focus on depth and ascent rates, which have nothing to do with the victims symptoms. By all accounts the dive was safe if with a fast ascent. So what killed this diver?