The ´Safety Stops´Debate.

[Mal Bridgeman]

I can't see this having been debated before but if it has then apologies in advance.

I have read a couple of posts recently from people who have had problems during their dive who then talk about further difficulties experienced on the safety stop.

One was a low on air situation following a freeflow (IIRC) and one was the buddy of a run away ascent. Both times nothing serious occured but it concerns me as to what people are being taught about safety stops in their training.

As an Instructor myself I must stress the importance of the safety stop and how it is good diving practice to carry one out but that in the majority of situations it is optional.

Life is simplified for today's diver by computers which even automatically count the time down for the diver. Unfortunately I think this is leading to a blindness of what the computer is helping the diver to achieve. So rather than using it as an aid to the planning and execution of the dive, it is becoming the master of the dive.

I stress to my students the important definition of Recreational diving which is that you can at anytime make an ascent directly to the surface if you dive on the tables*. (I know this is not true of all circumstances with some agencies but it is the case with the vast percentage of dives done on the tables of those agencies).

To give an illustration of what this can do for divers in Stoney Cove for example......Diving on the Stanegarth.....You can start your descent on the Stanegarth and so long as you start your DIRECT ascent to the surface within 40 minutes, and you ascend at the rate of 9m per minute, you can go directly to the surface without stopping.

If you then go and have a hot chocolate and bacon butty, get your tanks filled, adjust your personal comfort etc, so you have a surface interval of more than 1 hour and 7 minutes you can go and repeat the dive, and so long as you start the direct ascent to the surface within 31 minutes of the start of your dive, you can still make a direct ascent to the surface.**

I know that the safety stop helps ensure people do slow their ascents down at the point where the rate of pressure change is at its greatest so is a good thing.I am not trying to encourage divers to abandon safety stops.....but my opinion would be that if the diver has a problem in their dive (especially early on) then they should consider that the optional safety stop is just that ....optional.

What do others think?

Regards
Mal

* using the SSI system.
** using the SSI Doppler No-Decompression limits based on U.S. Navy Dive Tables

[Tony F]

but my opinion would be that if the diver has a problem in their dive (especially early on) then they should consider that the optional safety stop is just that ....optional.

What do others think?

I think that increasing the assent time and undertaking a safety stop, so long as gas permits, is always going to add more conservatism. Therefore even having suffered a problem if the stop can be safely undertaken then that would be my preferred course of action always.

Certainly the stop may be 'optional' under many circumstances, but any simple policy promoting safety has to be a winner in my book.

[nigelH]

It may actually give the same end result but I tend to think that all diving is decompression diving and I add the conservatism in my head. So if the computer/tables call for zero minutes of stops I might just add to it depending, of course, on gas and temperature.

This way my rules never change.

[Janos]

It's a good question.

I was on a dive early last year where my (relatively inexperienced buddy) started to get very stressed because of the strong current. We aborted, and although he obviously still agitated, I suggested we do a saftey stop. After about 1 minute he suddenly shot to the surface.

I learnt a lot from that dive.

In retrospect I think I should have not attempted to do the safety stop, but, having made the decision to abort the dive, and being well within no-deco limits, just carried on up to the surface, as my buddy could easily have gone the other way (down) which would have been much more serious.

Laters,
Janos

[MisterBlue]

Safety stops are very important - especially when regular repeat diving is involved, such as on a liveaboard trip.

Where circumstances permit a safety stop should always be completed, but it's essential to consider what a safety stop actually involves, and the circumstances of the specific dive. All a safety stop involves is spending time shallow before ascending to the surface.
The majority of dives will be on a reef or wall, or somewhere that allows a slow ascent. At Stoney, for example, you can dive as deep and long as you like, but once you get back to the shelf I'd consider any time spent there as part of the 'safety stop'. It can be planned as part of the dive, but the time spent bimbling in the shallows constitutes a stop. A UK scenic dive on a wall, or a Red Sea reef dive offer the same opportunity for a stop where there is something to see. 'Stops' like this often become longer than the standard 3min becasue there is actually a lot to look at.

Square profiles, the classic deep wreck, are different. Once you get back to safety stop depth there is generally nothing to look at, so stops are onerous and the temptation is to pay them lip service. If the dive is a one off, well, the safety stop is optional and can be treated as such, though better do it than not. If it is a part of a series of regular dives - a week at Scapa - I'd be less inclined to miss a stop, and might well spend additonal time there.

If something goes wrong underwater the optional safety stop becomes less important. The best place to sort problems is back on shore/the boat, with the surface the second best place - depending of course on what has gone wrong. Losing a fin is a pain, losing your air supply life threatening. It can also happen that time spent on a safety stop can permit someone to calm down and start functioning properly again, and lessen their apprehension about the next dive.

At the most serious level, DCS can be treated, drowning cannot.

Mike.

[Hoppy]

I may just be conditioned by my training, but I would always put the stop in, gas etc permitting.

Maybe it's overkill ? I honestly don't know.

I agree with NigelH that all diving is decompression diving, however, there are "accepted" limits whereby a direct ascent is "allowed". But again why push it if you don't have to.

Besides when I've been lucky enough to dive somewhere like Tahiti, that 3 mins is more time to watch the things I went to see. No bad thing in my book.

[MATTBIN]

I always pad my dive with a safety stop, or at least I try to, unless its a slow ascent up a wall or similar, even when on Nitrox, screw ups permitting (1 off).
However I'd suggest that a lot of people on here are into deco diving so that rules out the no safety stop option on most dives.
I think it a very good idea to consider safety stops early on in diving as essential, not optional, so the diver becomes aware of the potetntial dangers in diving and adopts a cautious rather tha cavalier I dont 'need' a saftey stop approach so that as he/she enters deco diving he/she is aware of the need of a stop (or several). It also creates a diver who can hold a stop and not just abandon bouyancy control in favour of the surface.
Obviously any equipment problem which results in going to the surface as a last option is better than drowning.

Matt

[DaveB]

This is a sore point for me. Safety stops a good for a number of reasons, all already covered, but divers must know enough theory to properly assess risk.

I have been on a live-aboard off Aussie where we were threatened with being banned from further diving if we did not conduct a 3 minute safety stop on all dives. A pair of Aussie divers missed the shot line on return and duly carried out the safety stop in 2 kts of current, (as they had also left the lee side of the reef). Afterwards they did say that they had wanted to come straight up as their computers were clear, but did the safety stops as "They were an absolute requirement". They were 300+ yards from the boat on reaching the surface and drifting away, luckily they were spotted by another guest and picked up by inflatable some 10 minutes later.

I have come across similar examples before and after this one. I strongly agree with doing safety stops, but not if it results in a more dangerous situation.

[Gavin Smith]

I've always tried to approach things in terms of "future proofing" my diving.

I'd rather be able to practice and hold a safety stop now even though I don't "need" to do them (no compulsory safety on my Aladin Pro) so that each dive I get the practice in.

Gavin

[Janos]

I have come across similar examples before and after this one. I strongly agree with doing safety stops, but not if it results in a more dangerous situation.

I think this is the nub of it. Personally if I was diving with a relatively inexperienced diver and we had an OOA situation, leading to a stressed trainee and an air share then I would probably [1] not do the safety stop but continue to the surface. I would now continue to the surface in the case of a panicking diver where I took the call to abort the dive, and other similar situations.

If the diver is stressed then there is a risk that they may lose it completely in which case it's better to be on the surface then at 6m.

Agree entirely with doing a safety stop on all dives that go to plan though.

Laters,
Janos

[1] - I say probably as I might stay down in a few cases. If I was on the 6m shelf at Stoney with no risk of them disappearing for example.