Pick apart my rescue: air-share ascent from 110'

[KenGordon]

@Marie13 posted earlier in “Cautionary tale for new divers” about a friend who is very early in his diving career, does not have experience to support good judgment, and appears to be an accident waiting to happen.

He’s not an accident waiting to happen. He was an accident that happened on Sunday and I rescued him.

I’m volunteering the details here for open discussion so that I can learn and improve for the next time that something like this happens.

Background
1. These dives took place on the wreck of the S.S. Wisconsin. She sits at roughly 110’ (~33m) to the top of the hull and 130’ (~40m) to the sand.
Edited to add: bottom temps on the wreck were 40-44°/5-6°C. There was one thermocline around 45 feet/14m.

2. We used a simple gas plan: monitor depth, air consumption, and NDL frequently; be back at the line and start ascent with at least three minutes of NDL and no less than 1000 psi (~70 bar) remaining in the tank.

3. After the dive, I learned that Buddy has only 25 dives and finished AOW earlier this week. He had a 40 cu. ft. (~6L) pony bottle with him. He does not have any rescue training.

Edited to add: neither of us had been to this wreck before. I have around 20 dives below 100' (~30m), a handful of which have been to 130'/30m. baed on our lack of familiarity, we didn't have a very set "itinerary" for our bottom time.

First Dive
4. Our first dive was uneventful. We descended to 115’ (~35m), swam a reciprocal course down the length of the hull (204’ long, ~62m), and returned to the line within our gas and time plan. Our ascent went well.

5. We had a one-hour surface interval.

Second Dive
6. We started with ten minutes of NDL time. On this dive, we stayed close to the ascent line on the bow. I made a very brief excursion to 132’ (~41m) to look at an object in the sand. I believe that Buddy was around 120’ (~37m) while I did this.

Edited to add: after my excursion, we formed up in a pair within a few feet of eah other. We then started returning to the line.

7. We were within ten feet of the ascent line with three minutes of NDL when I heard something, turned around, and saw that Buddy's primary reg was free-flowing (I think it was still in his mouth when I first saw him – I know he took it out at some point, but it might have been right before my next step.)

8. I immediately pulled my octo and attempted to give it to him. It felt like forever to get him to accept it. I’m not sure if he was too freaked out or narc’ed and didn’t follow what to do with it. Remember that pony bottle I mentioned? I never saw him reach for it, reach for the reg, etc. It was dead weight.
Edited to add: I had a very small amount of trouble getting him to cooperate for me to reach his valve and turn off his tank.

9. Once we had a good air source in his mouth and his tank off, we signaled OK and immediately started our ascent. I wasn’t sure how much of our remaining NDL we used up and I wanted to (a) avoid incurring a deco obligations and (b) get to a depth where our air would last longer. I believe I had 1200-1500 psi (~80-100 bar) in the tank at the start of our ascent.

10. Edited to add: I checked my computer and we had not entered deco at the start of the ascent. We ascended almost within kissing distance (36"/1m octo hose) for about 100’ to reach our safety stop.

11. I watched my SPG for the first 20 feet or so to get a sense of how much air we were using. Our consumption didn’t seem wild to me, so we ascended at 30fpm (~10mpm) to our safety stop.

12. During the ascent, I made eye contact several times and we signaled OK back and forth regularly. I showed him my SPG a few times so that he could see how much of our air supply remained.

13. When we hit the safety stop, I deployed his pony reg and handed it to him so that he could give me back my octo. The transfer between air sources went smoothly and we held the stop without further incident.

14. We conducted a short debriefing on the boat. I had managed to get his tank turned off with only 330 psi (~22 bar) left!
Edited to add: I had roughly 500 psi (~35 bar) remaining in my tank at the end of the dive.

15. I assumed that the freeflow was a mechanical failure (although he may have been breathing and inflating at the same time). At the time, I didn’t really think about the failure to deploy the pony as a skill issue, but I’m changing my mind on that.




As I mentioned, I learned after the dive that Buddy has relatively little diving experience and very little advanced diving experience. He has minimal training in self-rescue techniques (which I did not see him use), nor any other Rescue training.

I didn’t uncover this during the pre-dive briefing. Tactical error! All of my instabuddies going forward will have to sit through a much more thorough discussion and preparation. (However, I’m not sure how much of this would have affected the freeflow, other than changing the dive plan.)

I’m happy to answer more questions and take feedback and suggestions. My general feeling is that the rescue went well (we both arrived alive, un-bent, and with air in both tanks), but next time can always go better.

I think you were very lucky and possibly saved by this being a second dive limited by NDL time.

The standout bit for me is how much gas you were planning to have when you left the bottom.

70 bar is only 700l (600 allowing for regulator IP) so for two people between 35m and the surface at an average 2.25 ambient you are looking at 90 to 135l) minute (assuming a not excessively generous SAC 20l/m to 30l/m each for two people at 2.25) so apparently have about 6 minutes to do it. You actually used 450 to 650l (based on the 35bar remaining and starting up at 80 to 100) and didn’t need to supply gas at the safety stop. You say you were going up at 10m/m which ought only to take 3 minutes (plus a bit at the stop) so perhaps the gas consumption rate was at the high end.

I claim that a 10l cylinder is a bit small and 70bar is too little margin to be leaving the bottom. Your ascent may have used more gas than your planned reserve.

Unfortunately people often regard gas planning as an optional extra, even a ‘technical’ skill.

 

[Zef]

.

As you know for a OOA/OOG in a non overhead the you're simply donating the gas and making a controlled direct ascent to the surface.

I am not saying the above is wrong but it seems like an overly text book / classroom based mentality. In reality there are considerations that may cause one to consider not directly ascending to the surface such as an area with high boat traffic....in this case it may be beneficial to stay submerged and swim to (or closer to) the exit point...this is especially true if you are following a bottom that is a descending slope on the outward part of the dive...you can follow the ascending slope back. This may also be true if there are strong currents at the surface which may make linking up with the boat or reaching the exit point difficult.

Of course, if there is not enough gas left, in a non-overhead environment UP is the way to go...but in an emergency that is being brought under control directly up is not always the best answer. This highlights the necessity for an increased focus on gas planning as part of the pre-dive plan which is something not really focused on much in most recreational open water and advanced open water certification programs.

-Z

 

[johndiver999]

I think giving him the octo is better than handing him his own pony. Maybe he already used the air, maybe he forgot to turn it on, maybe it bled out most of the air without either diver noticing, maybe the pony had a free flow during the short excursion to 130 ft? Maybe the victim didn't go for the pony for a valid reason?

These reasons are all stretching things a bit, but it does point me in the direction of giving him the octo IF you have enough gas.

Also, it sounds like the ascent was made on a line, but if not, then it might have been very valuable to try to turn his air back on (after a minute or so) so he could use his power inflator in case of dumping too much air from the BC. Sinking in an emergency with no power inflator can be a serious problem if the victim has other "issues".

Switching to the pony at a shallow depth seems smart too. Good practice for him. Obviously he should have went for his own pony and probably asked the buddy to shut down the tank valve,

 

[doctormike]

It's not the wearing of the hose, yes it can be unwieldy if people need to de-kit in the water or with the long hose on a boat, but these are minor inconveniences that with a little thought are easily over come.

My feelings for OW are derived as thus: Sorry for the long post.

As you know for a OOA/OOG in a non overhead the you're simply donating the gas and making a controlled direct ascent to the surface. In Open water you'll need to generally take control of the OOG diver and manage the ascent.

In this regard either ascending up an anchor or shot line I see no need for 7' hose. Similarly with an ascent in the blue with a dSMB. That said I find the standard hose configuration too short.

As I've mentioned before, my main rig, is set up with 2 x 40" hoses, with both regs having a 90 degree swivel, and my Alt second coming under my left arm (a peculiar British way) and secured on a silicon bungee.

This I believe gives the best overall solution of hose lengths and flexibility, alleviates hose crossing issues and has the minimum of downsides (it doesn't matter which reg you donate). It would be acceptable for a "Tec dive to get the receiver to a stop before they can get onto a deco reg, however It would not be the optimum for a physical overhead like a wreck penetration.

I like for people to think about their gear setup rather than blindly follow a particular method.

Many many divers, really aren't that skilled with regard to donate. It's something they do in training , park and forget. Even those that practise (for the most part) do so in a controlled low stress environment.

When I teach Rescue, during the final scenarios, when I simulate OOA it's not with the nice calm OOA signal. No, I come at them with my mask off, reg out, eyes wide open "flailing" about. Even though they will have practised this as part of the course, and the OOA is briefed at least 50% freeze up with surprise and shock. Quite often I will end up halting the scenario putting my own reg in and mask on and then debriefing. This is with a normal rig. With Long hose some get into a real tizz.

Obviously this isn't' an equipment issue rather than a practise and skill issue. But this is the reality.

I'm a firm believer in the KISS principle (and the 6 P's - Prior Preparation Prevents P1$$ Poor Performance) so people having the simplest setup applicable to allow themselves to carry out the type of diving they choose, and thinking it through. A great example is the discussion on SM as to whether to use the standard long hose bungeed second or 2 long hoses. Pro's and cons for both and in the end a personal choice dependant upon your preferences (I prefer the latter especially on my DPV as its faster to donate a free reg)

In my early dive experience, I was as guilty as anyone of making my gear selection based on others' opinion or how shiney it was. More experienced divers got me to justify my equipment decisions by discussion and thinking. Sometimes I was right and sometimes I was wrong. They weren't trying to shame me, just get me to think my decisions through. And it was a great learning experience.

So in summary I have no objection to any gear rig - I only object to decisions that have been made without real thought behind it, (because they've read about it or want to look different etc etc) and then not taking the time to practice or get tuition in the operation or use of that config. That could be Long hose, Pony's etc etc

Good discussion though.

Thanks for the thoughtful reply! You are an instructor, I’m not, so I do defer to your experience to some degree, but here’s my take on your post.

I think that there is a range between “blindly following a particular method” and extensively doing your own testing of a wide range of options. When I adopt certain tech derived practices in recreational diving, it’s not just because of an appeal to authority but because most of these have been worked out over the years, based on a huge dataset of experience and multiple accident analyses.

So while it’s true that you can probably come up with an optimal hose length that is longer than the typical one but shorter than 7’ (or 5’). And maybe a longer hose does get you into a “fizz” with some rescues. I have tried it many times and haven’t found that, but again, maybe your experience is different. I don’t like the idea that a struggling victim is more likely to pull out a donated reg on a shorter hose than a longer hose, so there are obviously tradeoffs even if you aren’t doing a long swim out of a cave in single file. And, of course, I agree with you that whatever you adopt (long hose, pony, etc..) is worthless if you don’t train with it.

The larger issue is that optimizing gear and developing muscle memory is a good thing to do early on. Very few divers can guarantee that they will never be in an overhead environment in the future. The long hose gives you flexibility with (in my opinion) virtually no downside, and it lets you develop good skill that will be applicable in a wide range of conditions - open water, cavern, cave or wreck. Even if you never set fin in a cave, let alone do a cave rescue, trying to donate gas with a relatively short hose in any sort of overhead environment, even a relatively benign swimthrough on a sanitized shipwreck, can be difficult.

I understand that this idea of there being only one acceptable way of diving can be taken to extremes. I’m not a DIR diver, and I do see the pushback on that approach by people who want to make their own modifications of gear and practices. But at the other extreme, dispensing with a protocol that is easy to do, easy to learn and widely applicable (long hose, primary donate) just because your students are only training for basic OW is, in my opinion, not the best approach.

I don’t “blindly” accept anything. I am a CCR newbie, but I love discussing the reasoning behind everything that I learn about rebreathers and there is a lot more variability of gear and practices there than in OC. But at some point, I do accept the experience and recommendations of others without doing all of the testing myself.

 

[doctormike]

I think giving him the octo is better than handing him his own pony. Maybe he already used the air, maybe he forgot to turn it on, maybe it bled out most of the air without either diver noticing, maybe the pony had a free flow during the short excursion to 130 ft? Maybe the victim didn't go for the pony for a valid reason?

You get the victim plugged into a working regulator immediately. Not the pony. IMHO, that means the rescuer's working primary regulator, following which the rescuer switches to their backup. Using the rescuer's "octo" is a common alternative (although there is always a chance that that one isn't working well, which is why I do primary donate).

THEN, you check the pony, pretty simple to do. Turn it on if it's off, and check the SPG. If it's OK, and once the victim has had a few breaths and calmed down, you can put them on their pony for the ascent, so that if you get separated for any reason (current, surge, panic) they still have gas. If the pony is OOG for whatever reason, then you can share the rescuer's back gas.

 

[peeweediver]

First, thanks doctormike for always posting interesting thoughts. Helped me with ear issues leading to perforation a few years back. Both you and Diving Dubia have gotten me thinking about my set-up. Probably time to practice a few length alternatives while at our wonderful quarry. What makes these posts and the responses so invaluable is when thoughts are exchanged without judgement and we can sift through and consider new approaches to something we may have been doing the same way for 26 years. Very much appreciate the conversation and, again, the OP did great. Spouse and I already discussed our SS Wisconsin dive plan 4 weeks out because of the post.

Rob

 

[alvinsuper]

I don't see the issue with the OP choosing to donate their back gas instead of putting the victim on their own pony. I suppose that's SOP (at least as I was trained and in recreational dives). In those situations one reacts on muscle memory and mine dictates to donate my reg. It's also conceivably easier and faster to locate and handle your own gear, assuming you keep it nice and tidy and you practice, than to manipulate someone else's equipment while they're distressed and they may be about to flail/panic, if they haven't already.

 

[doctormike]

I don't see the issue with the OP choosing to donate their back gas instead of putting the victim on their own pony. I suppose that's SOP (at least as I was trained and in recreational dives). In those situations one reacts on muscle memory and mine dictates to donate my reg. It's also conceivably easier and faster to locate and handle your own gear, assuming you keep it nice and tidy and you practice, than to manipulate someone else's equipment while they're distressed and they may be about to flail/panic, if they haven't already.

Once again - First job in any rescue of an OOG diver is to IMMEDIATELY give them a working regulator from the rescuer's current back gas supply - Ideally the primary regulator that the rescuer was breathing off of. NEVER try to deploy an alternate gas supply for an OOG and distressed diver. They need working gas now.

The controversy was about whether - once the victim is breathing comfortably from one of the rescuer's regulators - it is advisable to switch the victim to their own alternate gas supply for the ascent.

 

[Dirty-Dog]

As others have said, I would have donated my long hose, but would have put them on their pony before the ascent. But you can't argue with success. Ultimately, results are what matter.

 

[Dirty-Dog]

Once again - First job in any rescue of an OOG diver is to IMMEDIATELY give them a working regulator from the rescuer's current back gas supply - Ideally the primary regulator that the rescuer was breathing off of. NEVER try to deploy an alternate gas supply for an OOG and distressed diver. They need working gas now.

The controversy was about whether - once the victim is breathing comfortably from one of the rescuer's regulators - it is advisable to switch the victim on their own alternate gas supply for the ascent.

Agreed. Donate first. Given that the OP mentions they ascended hanging onto each others BCD (which is the only thing you can do with short hoses) and given that I personally do NOT like that sort of ascent (makes doing things like shooting a bag problematic...) I'd almost certainly have put them on their pony prior to ascending.