Missed Safety Stop. Go Back Down?

[Steve_C]

The missed question is why did you miss it? If I have any sort of issue like cramps or equipment I would just rest on the boat. If I missed it because, say I was helping somebody else, or relaying information to crew for some reason, so that I was ok, I would go ahead and do the stop. I enjoy the stop unless it is rough topside and I am diving in a solo configuration anyway.

 

[John C. Ratliff]

From my perspective, the dive accident cited was not a "blown safety stop," but rather a blown decompression stop after a second dive to somewhere around 80 feet. I won't comment further on it, as there are too many unknowns.

Now, about the safety stop; this is a more recent procedure that helps prevent decompression sickness, and is more necessary when diving what we used to call the "knife edge" of the no-decompression limits. There are a certain number of people who have "silent bubbles," which was confirmed by Spence Cambell some years ago in his studies at Virginia Mason Research Center in the Seattle, Washington area. He also developed the doppler technique for identifying these "silent bubbles." For an interesting read, order his book, After the Swim. But missing a safety stop after diving to the knife edge of the no-decompression limits can put one in jeopardy. It's much better to not get to that place, and not dive close to those limits.

I asked Spence about the current technical divers who routinely dive decompression dives, sometimes with twins on their back and two or three other cylinders for decompression, but without a deck recompression chamber immediately available. Spence was in charge of diving to the top of the Cobb Seamount, and when asked about this at the recent Northwest Diving History Association meeting, he replied that these divers are really putting themselves in jeopardy. On the Cobb Seamount research dives, they had several occasions where they needed to use the recompression chamber, and these were dives to about 230 feet max.

Spence Campbell explains the precautions and dives on the Cobb Seamount, 270 nautical miles off the coast of Washington State.

My opinion is the same as Spence's, in that I don't feel divers should be routinely doing decompression dives without a backup recompression chamber immediately available.

SeaRat

 

[Bob DBF]

For everyone saying they wouldn't go back down, can you explain why?

Let's say you have 25%-33% of your air left, what would be the problem? How is it dangerous to go back down to 15 feet for a few minutes?

Say I was on a 2 or 3 dive day and was nearing my NDL with sufficient air, I would absolutely go back down for a few minutes to reduce my chances of DCS and think it would be stupid not to.

It would depend on why you missed the stop, and where your buddy is while this is all happening. If there is a problem the safest place is with your buddy on the surface.

The fact that you missed the stop implies you had (have) one problem, the incident pit is open for business. Submerging again places you in a more dangerous situation. The decision to return to the stop has to be as well considered as making another dive, which it is.

Safety stops are not mandatory. I wouldn't bother going back down, but I only started safety stops, and 30 fpm ascents when I bought a computer.



Bob

 

[CuzzA]

Where do you dive. Off the NC coast doing full safety stops is standard. Even in the Keys I have seen a number of folks doing full safety stops. I always do. I kind of like hanging there watching the underwater world go by.

Steve, I dive the Florida Gulf Coast. Perhaps my experience is unique because we have a lot of private spearfishing and divers want to get out of the water.

 

[CWK]

Novice divers have been known to press the wrong button and inflate their BCD when they actually want to deflate their BCD whilst they are ascending. This will cause them to shoot to the surface at speed, missing their safety stop. If they feel OK as the video says (have not burst a lung) then go back down and do the safety stop. If they feel unwell, then seek medical assistance.

 

[AdivingBel]

Personally, I've yet to see a diver complete a full safety stop. Can you believe it? I was shocked after getting certified. The safety pause is what I see in the real world. Again, NOT recommending that, just giving some perspective that there's a lot of divers doing some hardcore diving and the safety stop isn't part of their plan.

I get what you're saying. The truth is there is a difference between training and reality...it's, well, reality. I don't mean to be a nudge , but since this is the Basic forum, I'll offer a counterpoint...

I doubt I'm a "hardcore" diver. I'm a warm water, vacation diver (I have to be...I live in Missouri ), but I generally get in 100+ dives a year all over the place. I dive & travel with pretty experienced divers (the "usual suspects" in Coz, an NC group, and others as well as on my own) most with hundreds if not thousands of dives. I very, very rarely (almost never)see anyone in those groups blow a SS. You might not always see it, if they've been mucking around shallow at the end of a shore dive (or something like that), but they always do them. Hey WTF, they've lived to do a thousand dives, why not emulate them. That said, I would fully expect the response to "Hey, I missed my SS. I think I'll jump back in and finish it." to be "That's nice. Do what makes you comfy. I'm going to find the cookies." All IMHO, YMMV.

 

[Bowers]

the recreational tables are based on studies and reflect times without safety stops in wich divers had VERY low probabilities of DCS symtoms. the safety stop is designed to increase ones margin of safety (especially if youre not in the shape as someone in the navy). So with that basic understanding i would highly recommend safety stops but also would not make a big deal of accidentily missing one now and then, providing all other dive peramiters are within recomended limits.

 

[boulderjohn]

That said, I would fully expect the response to "Hey, I missed my SS. I think I'll jump back in and finish it." to be "That's nice. Do what makes you comfy. I'm going to find the cookies." All IMHO, YMMV

Are we all aware of the fact that the DAN video being questioned talked about the scenario where you blow your safety stop, reach the surface, and then descend immediately? It is not talking about reaching the surface, getting back on the boat, looking at your computer, and saying, "You know, I missed a safety stop. I think I will go back into the water and do it now."

That is an entirely different animal.

 

[CuzzA]

I get what you're saying. The truth is there is a difference between training and reality...it's, well, reality. I don't mean to be a nudge , but since this is the Basic forum, I'll offer a counterpoint...

I doubt I'm a "hardcore" diver. I'm a warm water, vacation diver (I have to be...I live in Missouri ), but I generally get in 100+ dives a year all over the place. I dive & travel with pretty experienced divers (the "usual suspects" in Coz, an NC group, and others as well as on my own) most with hundreds if not thousands of dives. I very, very rarely (almost never)see anyone in those groups blow a SS. You might not always see it, if they've been mucking around shallow at the end of a shore dive (or something like that), but they always do them. Hey WTF, they've lived to do a thousand dives, why not emulate them. That said, I would fully expect the response to "Hey, I missed my SS. I think I'll jump back in and finish it." to be "That's nice. Do what makes you comfy. I'm going to find the cookies." All IMHO, YMMV.

I don't believe skipping the optional safety stop is the norm and like I said, it should be done. My point was that I personally witness pretty aggressive diving, mostly commercial and private spearfishing where very slow and controlled ascents are the norm, but safety stops are often just a pause or slow down, yet these guys may be doing 6-8 ND dives a day, every day for several days to 100-130 feet and no one is getting bent. They've been doing it for decades.

So when you put that into perspective to the basic forum which for most here would be 2 to 4 dives a day at 60 feet or less, going back down for a missed safety stop hardly makes sense. Of course I realize there's always that outlier who does everything right and still gets hit, but the odds are really slim. Going back down, likely alone, with a few hundred pounds of gas, while trivial, provides little to gain considering the possibilities of other things going wrong.

 

[MaxBottomtime]

I made less than five safety stops during my first 1000 dives. I didn't start making them on a regular basis until I began diving with Merry, who was certified at a time when all the agencies were recommending safety stops.