Got quite a scare today...

[Charlie99]

Yeah, you really shouldn't try in-water recompression if you are NDL diving. If you take a hit it is likely to be mild, and likely to clear up with 100% O2 on the surface. If you take a hit though and go down to IWR, you might have to deal with a symptom like paralysis while under 20+ feet of water, you're also not likely to offgass as efficiently with EAN trying IWR as you are with 100% O2 on the surface..

Omitted deco procedures or immediately going back down to stop depth after surfacing is not the same as in water recompression.

Going back to depth immediately after a polaris ascent to the surface will minimize bubbling and prevent further bubbling. Your comparison of efficiency of offgassing with EAN vs. 100% O2 at the surface is not relevant to this prevention of bubble formation.

Yes, IWR has very significant risks. Yes, going back down for a missed stop has risks, but IMHO, there are a lot of cases where the risk/reward ratio is such that going back down is a GOOD idea. El Orans had close monitoring since he was breathing off his buddies long hose.

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Good luck in your DIR-F training, El Orans, but what you really needed in your situation is the basic PADI OW training ---- stop, breathe, think, act.

Simple to say. Not as easy to do.

Charlie Allen

 

[Ayisha]

it took me too much time to dump enough air. On the surface my Mosquito indicated that I had missed a stop (I probably did not see the "slow"-warning which was then upgraded to a mandatory stop).

Doesn't the Mosquito have an audible signal? Perhaps you could turn it on to be safe...

PS. If you had a LOT of air to dump, then you had a lot of air in your BC at depth. So you were probably overweighted, and you were compensating by adding air at the bottom. If you drop some weight, you might become neutrally buoyant.

One of my instructors told me a few years ago that when you barely have to adjust your BC during a dive (descending, changing depth, ascending), you know your weighting is bang on.

 

[Sideband]

Yes, IWR has very significant risks. Yes, going back down for a missed stop has risks, but IMHO, there are a lot of cases where the risk/reward ratio is such that going back down is a GOOD idea. El Orans had close monitoring since he was breathing off his buddies long hose.

Charlie Allen

I don't know the guy he was with but from what El Orans has said
the guy doing the "close monitoring" kinda missed a thing or two in the first place. He didn't handle his buddies free flowing reg. well imo. You trust his rescue skills more than I trust his Basic OW skills. Obviously everything worked out ok and I'm not calling the guy a bad diver. It's really easy to quarterback from here. I'm just looking at potential problems which can compound to make a disaster.

Joe

 

[H2Andy]

One of my instructors told me a few years ago that when you barely have to adjust your BC during a dive (descending, changing depth, ascending), you know your weighting is bang on.

this is a great point... up to a point.

for example, i wear no weight whatsoever, and use only an aluminum backplate, but
because i have to haul a 95 steel cylinder when i cave dive, i am always negative past 50-60 feet, so i do have to add air -- a lot more than i would like (the alternative is hitting the bottom -- not a good thing). also, just in case someone is wondering,
i don't just plop to the bottom. i add air in increments as i go down, so by the time
i get to the cave portion, i am fairly neutral, then all it takes is a couple more bursts.
but all in all, i wish i didn't have to add so much air -- just added drag.

i have just switched to a dry suit. i'm curious to see if that has an effect.

 

[Rick Inman]

Glad you're all good!!!
My first couple 'o free-flows got my stress level up a bit, which causes narrowing perception. Maybe this happened, and instead of doing a nice relaxed ascent, you started making what I call a "stressed, but controlled bee-line for the surface", realized you needed to dump, couldn't find your hose on the new BC quick enough, and bingo, you're on the surface.
Last winter when I was diving with a non-winterized regulator, we had free-flows all the time, and it became 2nd nature to share air, turn off the gas for a minute, turn the tank back on sans free-flow and continue the dive. So, unless you can't stop the free-flow or you are too stressed, I see no reason to call the dive.
I also see nothing wrong with heading back down for a missed safety stop on a NDL dive.

 

[mweitz]

LOL

It wasn't long ago that it was a 60 fpm ascent.

My wife has "bent" her mosquito twice in the last couple of weeks. That thing is wacky. I really have to sit down and figure out how to make it just a bottom / depth timer.

No computer is "very" accurate. There are too many variables and people are all different. If a computer is "conservative" and if you don't follow it you are likely to get bent it would mean that everyone using a "liberal" computer would get bent all the time. . The logic just doesn't follow.

Mark

Suunto Computers are RGBM (Reduced Gradient Bubble Model), are very conservative and also very accurate. Exceeding the 30 fpm ascent rate for more than a few seconds triggers a mandatory stop @ 20-10 ft.

Anyone that I heard of that ignored or just didn't pay attention to the warnings of their Suunto usually paid the price by taking a hit...

 

[mweitz]

El Orans, sorry to hear about your little mishap.

Can you give some detail on when it started to tingle exactly? Were you still in the water, out of the water? How far of a walk was it to where you remove your gear? How long after you got into the water did it take for the tingling to go away?

Thanks,

Mark

 

[El Orans]

To start, I'm glad everything is ok.
I have several questions though. The first is how you got a mandatory stop after a few minutes at 38'.

An ignored warning is upgraded to a mandatory stop.

The next is what did you do to stop the freeflow?
This is something that really should have been handled at depth IMO. That early in the dive you both surely had a ton of gas left. You could have breathed off the flowing reg. in the mean time. A freeflow not caused by freezing isn't a major event and in your particular situation should not have been a big deal at all.

I had a working regulator and plenty of air. Since I was at 9m/30ft when it happened (and I knew that this was the end of the dive) I just chose to ascend.

What do you mean when you say, " it took me too much time to dump enough air"? How different is your inflator hose that it would make a difference how many dives are on that wing?

My inflator is tied down to my harness whereas I'm used to having my inflator not tied down.

Why weren't you looking at your computer as you ascended, especially if you were in a position to possibly have a mandatory stop?

I was too busy trying to dump air.

What did DAN say about going back into the water? I've been taught in all 3 classes I've taken that we shouldn't go back down for a missed stop or fast ascent. Instead get on O2 ASAP.

I've been taught the same. But I knew that it would take me at least an hours drive to get O2. I was feeling pretty good apart from the fingers on my left hand. So, I did consider it a minor incident which could probably benefit from a safety stop and a slow ascent.

as to the free-flow, i'm curious if you tried to stop it at depth or if the thing just kept putting out air anyway.

I briefly tried to stop it but the only thing that stopped it was closing the valve.

i'm also curious about going down again to do deco. did DAN say anything about that?

It was not deco, just a safety precaution.

but what you really needed in your situation is the basic PADI OW training ---- stop, breathe, think, act.

Yep.

Doesn't the Mosquito have an audible signal? Perhaps you could turn it on to be safe...

I cannot hear any signal through my hood (see current profile pic).

I don't know the guy he was with but from what El Orans has said the guy doing the "close monitoring" kinda missed a thing or two in the first place. He didn't handle his buddies free flowing reg. well imo.

He offered me his primary at depth so he could close the valve after I had taken it. That would have been a better solution.

My first couple 'o free-flows got my stress level up a bit, which causes narrowing perception. Maybe this happened, and instead of doing a nice relaxed ascent, you started making what I call a "stressed, but controlled bee-line for the surface", realized you needed to dump, couldn't find your hose on the new BC quick enough, and bingo, you're on the surface.

How true.

So, unless you can't stop the free-flow or you are too stressed, I see no reason to call the dive.

When I reopened the valve on the shore, it started freeflowing again.

Can you give some detail on when it started to tingle exactly? Were you still in the water, out of the water? How far of a walk was it to where you remove your gear? How long after you got into the water did it take for the tingling to go away?

I was standing on the beach, a few minutes after the dive. I hadn't removed my gear yet. When I arrived at depth (7m/23ft) all was fine again.

Laurens

 

[Diver0001]

He offered me his primary at depth so he could close the valve after I had taken it. That would have been a better solution.

Laurens, I'm glad to see you're getting the most out of your DIR-F...

Don't get too wound up about it not going like you wanted it too once you had all the time in the world to think about it..... You've mentioned this twice now and I suspect you felt that you didn't perform well by not sharing air.....

Your idea of taking more time to assess the situation (stop breathe think do) is right on the money and that's putting the horse and the cart in the right order. The *solution* (share air and ascend or just ascend) isn't really relevant at this point. Once you get that calm collected reaction working for you the solutions will come without forcing them. At least to my way of thinking anyway...

What did your instructor say about it?

R..

 

[SDAnderson]

So your day ended up being more exciting than you planned, did it?

Few people even scratch the surface, much less exhaust the contemplation of their own experience.​

Randolph Bourne​

Sorry for the scare you and your buddy had but it sounds to me like you're doing just fine. Don't beat yourself up too severely; you did more things right than you did wrong, you didn't get hurt and you're learning from your mistakes. That's what the class (and life) is all about. In the long run, this incident will make you a better diver and give you a great story to swap during surface intervals, so life is good.