no safety stop after 53' dive

[heavierthanlead]

Runaway ascents are common among new divers who don't yet have a complete handle on their buoyancy control (operative word emphasized). It's not just about "leveling off" at depth, but the means to control yourself, throughout your descents and ascents. The minute you decided to hover 10' above them, did you instinctively reach for access to your deflator button? You will, in time...

 

[Crush]

Great that you didn't follow the DM on the swim-through if you were uncomfortable. Did he/she discuss the swim-through with you in the pre-dive brief? Did you ask him/her about not doing it if you felt uncomfortable?

It is too bad that you weren't aware that you were surfacing. Usually my ears will "tell" me when I am ascending. Also, I always watch for particulates in the water (they are always there no matter how clear the water) - they tells me if I am holding my depth (assuming no down- or up-welling) without needing to consult my gauges. With the dive profile you described missing the safety stop should not be an issue. If, however, you were deeper and (say) diving a drysuit you might have conceivably been able to get into a feet-first runaway ascent - this is something that you dearly want to avoid.

Final note: this A&I thread is full of cases where junior divers indicate to a DM that they are low on air, and the DM (who is typically leading a large group in a warm water destination) continues the dive so as not to disappoint everyone else. In such a case I would recommend that you indicate your departure to the DM and surface on your own (did you discuss in your pre-dive brief at what pressure you will terminate your dive?). If the DM is too far away or swimming too rapidly such that you would risk OOA if you tried to contact him/her I would personally (and others may disagree here) indicate to the closest person that you are ascending and surface on your own. Surfacing without a line can be scary the first few times - this is a skill that I practice a few times a year just to keep it current - watch your gauges and watch particulates to monitor your ascent rate. Finally, when on the surface, a surface marker buoy will help the boat crew spot you if you are not where they expect you to be - always carry an SMB with you in open water.

 

[supergaijin]

I would mention that a single dive without SS is one thing, however when doing multiple dives over multiple days, safety-stops become much more important. Multiple dives throw in many other factors mentioned above such as fatigue, cold, dehydration etc.

Dive computers are conservative- some are more aggressive than others. If you own a more 'aggressive' computer, again safety stops become a bit more important.

A missed safety stop can be 'fixed'. You can descend immediately (air supply and conditions permitting) and complete your safety stop. Bubble formation tends to occur around 15mins after surfacing.

A missed safety stop dramatically increases the amount of silent bubbles, which are thought to increase the chances of 'real' bubbles on subsequent dives. One study showed that a one minute stop at 6m, and a further 3 min stop at 3m reduced the amount of these silent bubbles to practically zero after a surface interval of just 45mins. I can't remember the exact profile on this test (ie. depth and time) but it was typical of a recreational dive to around 25 meters.

Personally I aim for a 5min safety stop on most of my dives- especially the last of the day. I also try to make an anally slow ascent from 3m to the surface. Slowly winding up an SMB line really helps you make a sloooow ascent.

 

[Crush]

A missed safety stop can be 'fixed'. You can descend immediately (air supply and conditions permitting) and complete your safety stop. Bubble formation tends to occur around 15mins after surfacing.

I wouldn't advocate that policy. Instead:

If the problem is a blown "safety" stop, it can be ignored, it is a non-issue, never return to the water to "make up" omitted "safety" stops.

If the problem is a blown required decompression stop and the diver is asymptomatic, then the diver can return to water withing 5 minutes, the procedure for omitted decompression may be followed.

If the problem is a blown required decompression stop and the diver is symptomatic, then diver should be placed on oxygen and transported to the nearest chamber as quickly as possible.

Only when the problem is a blown required decompression stop resulting in a symptomatic diver, and it is not possible to transport, should IWR be attempted, and then only when an operation is prepared, equipped and drilled for IWR.

 

[idive2]

As RJP has mentioned being unaware of an ascent has more concerns than just getting bent.
One major one would be getting struck by a boat overhead or you impacting your own boat.
The first thing I do when I hear a boat overhead is check my depth to decide if any action
should be taken. Good call on not following the guide on something you were uncomfortable with.
Work on always knowing your approximate depth and closeness to the surface and with a little
buoyancy fine tuning you should be good to go.

 

[chrpai]

Thalassamania, why the difference between a safety stop and an asymptomatic deco stop? I can think of several reasons (more like assumptions and risk analysis ) for this but I'm struggling with the "never" part for a safety stop.

 

[openmindOW]

Shellski,
Thank you for posting on this Forum. Welcome to the Dive World.

I trust that you are still asymptomatic at this time.

As other posters ahve said, you're probably going to be fine. However, I don't know what your dive profiels were like.

Mistakes happen in diving. You have learned from this experience and you will be a better diver as a result.

Keep diving. Any diver can beenfit from additional training, and you might enjoy taking some additional classes.

Stay well.

 

[boulderjohn]

Thalassamania, why the difference between a safety stop and an asymptomatic deco stop? I can think of several reasons (more like assumptions and risk analysis ) for this but I'm struggling with the "never" part for a safety stop.

Since Thal was only quoted and is probably not aware of your question, I will try to answer it.

In general, it is believed that if it is simply a case an omitted decompression and the diver can get back in the water quickly, then it is safe and helpful to return and do the stop. Different agencies have different teachings on this, but that is the general thinking.

If, on the other hand, you are showing signs of decompression sickness, you should not return to the water because it is not safe. If the symptoms suddenly get significantly worse, you are at risk of drowning.

If you are symptomatic and return to the water, the term covering that practice is no longer omitted decompression. It is now called In-water Recompression (IWR). IWR is very controversial, and it should only be attempted in extreme circumstances by people who know what they are doing and have the appropriate equipment. I have three different friends who were successfully healed through IWR, but in each case they were following one of the established IWR protocols carefully, and they had the appropriate equipment for doing it. In contrast, in the well-known case in Cozumel last year, a symptomatic diver returned to the water on her own with no such guidance or equipment. many people believe that if she had instead gone on oxygen and headed immediately to the chamber, she might have lived.

If you begin to show signs of decompression sickness while doing the omitted stop, then your situation has changed and you should get out of the water immediately.

 

[supergaijin]

I read a difference being that one situation is ascending 'knowingly' without a safety stop, the other with an uncontrolled ascent, ie. a 'blown' SS. An uncontrolled ascent probably exceeds the recommended ascent rate of 10m/33ft per minute- especially in the last few meters which are thought to be the most important.

In an uncontrolled ascent, (with a probable fast ascent), all bets are off. Safety stops can be safely omitted only if correct ascent rates are maintained.

 

[spectrum]

Missing the stop is no problem. It removed one riskmlimitewr but it is above and betond the table requirements.

When you descrive following above you were either venting your BC to reman neutral as you climbed or was wearing minimal neoprene and had an empty BC. Your dscribed rate does not suggest a runaway ascent.

The big oportunity others have stated is to improve you situational awareness. Sensations in your ears, terrain and body pitch and your depth gauge. Even the lighting should have warned you of change. Bottom line, a little more focus.

Yes you would have heard a power boat but those kayaks can vb stealth.... konk!

Pete