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Major Clanger
11-02-2013, 06:36 PM
...solo technical diving on a ccr. I'm not the only one, many others out there I'm aware about. Not a surprising mindset given how self-sufficient the breather makes individual users. Putting the rights and wrongs of it to one side, what do those that solo dive do to increase redundancy and mitigate risks. I have several things up my sleeve to which I'm adding a separate small O2 cylinder for boom scenarios and so on. What do others do to enhance their units should the poo hit the fan?

Timw
11-02-2013, 06:57 PM
1L O2 bottle with hose run down the lung so can be plugged into the O2 manual add.
BOV plumbed into off board deep bail out.
Mixed gas bypass plumbed into off board deep bail out to add dil or for semi closed
Shearwater on secondary
HUD on primary
Hose on 50% to plug into O2 manual add for semi closed
2 75m reels with CO2 blobs - if I have a problem on the bottom away from the shot I want a blob up as soon as possible and a line to the surface is a huge reassurance when it's all going wrong.
Yellow blob
Several cutters
Spare mask

That's about it!

SoggyBottoms
11-02-2013, 06:59 PM
are you really solo diving?
there ain't that many times you step off a technical boat when you're in the water alone
mebbies if you're first in or last out

my personal preference is to solo dive with a Buddy or Team




<off not of>

Major Clanger
11-02-2013, 07:16 PM
2 75m reels with CO2 blobs - if I have a problem on the bottom away from the shot I want a blob up as soon as possible and a line to the surface is a huge


Following suit on this. Used to use a reel and carry a spool for backup but have come around to thinking a spare reel is better than a spool.


are you really solo diving?


Yep, on just about every South and East Coast dive last year. Day boats, same ocean/same wreck dives, not technical charters, with depth and deco obligations making them technical dives.

Timw
11-02-2013, 07:28 PM
Yep, on just about every South and East Coast dive last year. Day boats, same ocean/same wreck dives, not technical charters, with depth and deco obligations making them technical dives.

Same for me. My dives also tend to be same wreck as I'm generally taking pictures and my "buddy" is poking around somewhere.
I plan on being solo so it is a bonus when we surface together.

The other essential bit of kit is the MP3 player :)

Gary
11-02-2013, 07:45 PM
Following suit on this. Used to use a reel and carry a spool for backup but have come around to thinking a spare reel is better than a spool.

always two full reels for me, christmas tree looking but there if I ever needed them

each reel was pre-fixed with dsmb ready to fire

Gary
11-02-2013, 07:50 PM
...solo technical diving on a ccr. I'm not the only one, many others out there I'm aware about. Not a surprising mindset given how self-sufficient the breather makes individual users. Putting the rights and wrongs of it to one side, what do those that solo dive do to increase redundancy and mitigate risks. I have several things up my sleeve to which I'm adding a separate small O2 cylinder for boom scenarios and so on. What do others do to enhance their units should the poo hit the fan?

the steel 1L suit inflation tins are good for this

Timw
11-02-2013, 07:59 PM
As well as having redundancy, I think the critical thing is being able to use it without adding stress if you have a problem - hence the two full (identical) reels and CO2 blobs.
Being set up for semi closed is also extremely useful and reassuring as a gas extender if you've bailed.

Major Clanger
11-02-2013, 08:16 PM
As well as having redundancy, I think the critical thing is being able to use it without adding stress if you have a problem .

On that note, I'm still thinking through whether to have the spare o2 already plumbed to the O2 MAV or only fit it should there be a problem. Probably go for the latter but see pros and cons.

BTS
11-02-2013, 08:31 PM
what do those that solo dive do to increase redundancy and mitigate risks.

to achieve both the above I solo dive with another diver... I find this the easiest way to mitigate risk and increase redundancy.

What are you plans for self rescue if you tox?

Mark Chase
11-02-2013, 08:36 PM
IMHO all diving is ultimatly a solo event so hardly a Taboo. Buddy diving outside a new love afaire or family member you love unconditionaly, is blissfull ignorance / stupidity

deleat as apropriate.

The last Taboo for me is Alpinist diving.

Its a bit like saying screw you to every one who cares for you. Its the ultimate in selfishness / stupidity

deleat as apropriate :D

ATB

Mark

Barrygoss
11-02-2013, 08:44 PM
Yep, on just about every South and East Coast dive last year. Day boats, same ocean/same wreck dives, not technical charters, with depth and deco obligations making them technical dives.

Then start using technical boats and not pushing rec boats into places they aren't capable of helping.
Otherwise you're really alpinist diving, just without recognising it.
B

Major Clanger
11-02-2013, 08:58 PM
Then start using technical boats and not pushing rec boats into places they aren't capable of helping.
Otherwise you're really alpinist diving, just without recognising it.
B

Nope, don't recall one boat I've been on ever advertizing itself as a recreational boat only, insisting on buddy pairs in its terms and conditions, nor complaining after a dive when divers have gone in to deco either on open or closed circuit. Skippers will decide for themselves the limits of diving they permit from their boats. Alpinist? Far from it.

ebt
11-02-2013, 09:01 PM
2 P's. Prevention and paranoia.

Prevention is simple stuff like always running pure o2 any time Im above 6m (lets the loop volume/breathing resistance act as an 'alarm') and critically letting breathing rate dictate work rate (not the other way around).

Paranoia, speaks for itself (or maybe whispers in your ears).

Major Clanger
11-02-2013, 09:19 PM
The last Taboo for me is Alpinist diving.



Can't foresee a situation where I would ever intentionally dive without oc bailout but can appreciate that some may take the view that for certain dives it's just not possible to carry enough gas. That aside, I'm sure many pay little more than lip service to adequate bailout planning. May look like they're carrying enough gas but not in the event of...just pushing their luck.

Barrygoss
11-02-2013, 09:25 PM
Nope, don't recall one boat I've been on ever advertizing itself as a recreational boat only, insisting on buddy pairs in its terms and conditions, nor complaining after a dive when divers have gone in to deco either on open or closed circuit. Skippers will decide for themselves the limits of diving they permit from their boats. Alpinist? Far from it.

Lol.
The fact it's not advertising itself as a rec boat, means it's a rec boat that lets you push the TTS to what 20/30mins? and doesn't care about you.

The buddy pair thing is the misnomer, the boat is your third (4th if you're gueeee) buddy.
These boats, are they putting in a lazy shot as a minimum? Are you seeing 100mins TTS on the dive and then thinking its a long fecking way home?

Do the math on a 50m/30min dive. You've just done mod 2, can you bail from that solo to the surface, you've got two cylinders, what's your gas choices? Or would you need some assistance?
A tec boat is one very early step toward managing risk, the first step really. The second is the diving "team".
And yes I know you're trolling me, but I've had a long day in London and I'm grumpy :p

B

Major Clanger
11-02-2013, 09:32 PM
Lol.

And yes I know you're trolling me, but I've had a long day in London and I'm grumpy :p

B

I thought the same when you ignored the request in the OP ;)

Barrygoss
11-02-2013, 09:37 PM
I thought the same when you ignored the request in the OP ;)

I thought I'd answered that:
Take a buddy, a boat: a shit load of gas (available from either 1 or 2) and/or anything else needed to surface from looking at a scrapyard underwater.
B

Major Clanger
11-02-2013, 10:00 PM
What are you plans for self rescue if you tox?

How likely is it that anyone who tox's could be safely brought to the surface from depth and survive? Statistically, it must be pretty slim. Would like to see some unbiased research on this.

Barrygoss
11-02-2013, 10:02 PM
How likely is it that anyone who tox's could be safely brought to the surface from depth and survive? Statistically, it must be pretty slim. Would like to see some unbiased research on this.

Ping nickb for his experiences ;)
B

Major Clanger
11-02-2013, 10:28 PM
Ping nickb for his experiences ;)
B

Read the incident report a while ago. The pit started to open a while before the dash to the surface from the shallows. He in effect self-rescued iirc, don't recall a buddy making much difference. Can we keep this discussion to the op for those that dive on their own to comment on? I'm interested in enhancements to units that individuals may make.

BTS
12-02-2013, 05:24 AM
How likely is it that anyone who tox's could be safely brought to the surface from depth and survive? Statistically, it must be pretty slim. Would like to see some unbiased research on this.

More likely if they have a buddy... It is not a difficult thing to overcome if you have assistance, there is protocol for dealing with a toxing diver. You will be hard pushed to get out of that one alone. Denial is a poor show.

I fail to get all this solo at depth bollox, there are plenty of people about to dive with and having a buddy doesn't mean holding each others hands all the way.

Macho bollox IMO.....

Major Clanger
12-02-2013, 06:10 AM
Denial is a poor show.
.

Indeed. Divers "with buddy's" are often in reality on their own but won't admit it. There's no doubt many a blissfully ignorant diver that thinks a buddy will save them from an ox tox at depth. Without a FFM, or possibly a gag, all I see a buddy doing in this scenario is making sure the family have a body to bury as I doubt a full-on event, convulsions and all, would be survivable. Could be wrong, would like to see strong evidence to the contrary...Question for a different thread - how survivable is an ox tox (say for example at 60m with a 45min TTS); what danger is there to a buddy trying to bring them both up alive.

It's not macho bollox; it's personal choice. My choice is to dive alone when it suits, taking measures beforehand with stuff such as optimal configuration to lower risks as much as possible. Burying the concept under the carpet and poo pooing it, helps no one.

BTS
12-02-2013, 08:50 AM
Equally burying your head in the sand regarding scenarios where it is better to have a buddy than not just because you have no 'strong evidence' is naive at best.

Your toxing buddy with deco obs stands a better chance assisted than not, if this means hitting their up button and bending them so a boat can recover them or assisting them to a safe depth and helping them deco out then that may make the difference between a burial and a chance at recovery.

Either way there is no need for the buddy to miss their stops.

Toixing solo has only one outcome.

Of course, this is your risk to manage and your decision to make.

BTS
12-02-2013, 09:06 AM
A further thought, I asked what you plan was to get out of a solo tox, so far your plan seems to consist of dying. Is that it, you are going to let a survivable event take your life?

Major Clanger
12-02-2013, 10:01 AM
I don't plan to get in to it in the first place, which is why I'm interested in optimum configuration and additional checks. Avoidance in the first place is far better than cure. Either way, tox'd at depth, the outcome's pretty final without or without matey alongside to drag you up. Think it through, think about the physical response the body undergoes when tox'd and what little someone else can do to prevent the other drowning, think about the management of a CBL, holding in the DSV, not letting water in while managing everything else, think about the impact of DCS if coming up quick and missing stops. If you can't treat the person on the scene quickly enough, there's no chance after bringing them up. Not accepting a survivable rescue is unlikely is blinkered.

BTS
12-02-2013, 10:13 AM
I don't plan to get in to it in the first place

Seriously, that is your plan?

Awesome....

bobdob
12-02-2013, 10:18 AM
Gary, have you thought about contacting Mr Powell and doing his Tech Rescue course ? He could possibly fine tune it to CCR as you have now gone down that route. From it you may get pointers towards the self sufficiency questions you have, and answers to issues others have raised.

Major Clanger
12-02-2013, 10:35 AM
Seriously, that is your plan?

Awesome....

Better than the lar lar land of expecting to survive it.

Major Clanger
12-02-2013, 10:39 AM
Gary, have you thought about contacting Mr Powell and doing his Tech Rescue course ? He could possibly fine tune it to CCR as you have now gone down that route. From it you may get pointers towards the self sufficiency questions you have, and answers to issues others have raised.

Bob, I've done tech rescue on the CCR and one of Mark's solo diver courses and drawn a number of conclusions. The more I know about ccr rescue, the less I believe that certain events at depth with a deco obligation have a get out of jail card. That's not to say I wouldn't do all I could should I find a casualty or a buddy has a problem; it's just a conclusion I've drawn for my own position and realistic expectations about the outcome. I don't want anyone else risking their own life to save me from something I don't think I will live through. So I move on with the planning assumption of an ox tox most likely being non-survivable with or without a buddy.

BTS
12-02-2013, 11:03 AM
Better than the lar lar land of expecting to survive it.

There is a world of difference between expecting to survive and increasing the odds.... The best way to increase the odds is to have someone help you out of it...

Major Clanger
12-02-2013, 11:26 AM
There is a world of difference between expecting to survive and increasing the odds.... The best way to increase the odds is to have someone help you out of it...

I think that in reality there would be little difference. Increased likeliehood of two or more casualities, not just the original one. Again, personal choice if someone wishes to take that risk attempting the rescue of another.

bobdob
12-02-2013, 11:44 AM
Bob, I've done tech rescue on the CCR and one of Mark's solo diver courses and drawn a number of conclusions. The more I know about ccr rescue, the less I believe that certain events at depth with a deco obligation have a get out of jail card. That's not to say I wouldn't do all I could should I find a casualty or a buddy has a problem; it's just a conclusion I've drawn for my own position and realistic expectations about the outcome. I don't want anyone else risking their own life to save me from something I don't think I will live through. So I move on with the planning assumption of an ox tox most likely being non-survivable with or without a buddy.

Ah, didn't realised you'd done one. Sounds like you drew the same conclusions as me, in certain scenario's, it's a loose-loose situation.

BTS
12-02-2013, 11:49 AM
Recuing a toxing diver isn't complicated if you know what you are dealing with, at the right moment the rescuer simply needs to assist the ascent...

Major Clanger
12-02-2013, 12:21 PM
I've got CBL's on breathers just about sorted. Quick check, hold in dsv, open opv, dil flush, perform cbl, keep dsv in place etc; practiced it enough times. Straight forward enough to undertake.

Timw
12-02-2013, 01:07 PM
Recuing a toxing diver isn't complicated if you know what you are dealing with, at the right moment the rescuer simply needs to assist the ascent...

Have you ever tried lifting an unresponsive diver from depth? There is no 'simple' about it - especially on CCR with additional buoyancy sources to control, as well as maintaining a breathable gas on ascent at what will be a variable rate at best. That's before you start thinking of starting your stops which could start anywhere from 50-30m. Even if you blow through the deep stops, you'll need to spend significant time at 20m upwards. Are you going to try to hold them at the stops, send him up alone as a buoyant ascent or miss your stops to get him to the surface? Whichever way you play it, the odds are very much against a successful outcome for either diver.
The original post was about mitigating the risks as far as possible with your kit set up.
I'd rather plan for worst case alone than rely on someone else getting me out of trouble - you make a huge assumption that the person you're diving with is actually capable of carrying out a successful rescue from depth.

WFO
12-02-2013, 02:05 PM
The commercial lot used to do bend and fix methods... out of the water, into a chamber.

I'd seriously consider taking someone up to the surface, making sure they were bouyant and going back down to decompress. Not going to be good for you but I don't think it's going to kill you, amount of deco depending.

BTS
12-02-2013, 02:09 PM
you make a huge assumption that the person you're diving with is actually capable of carrying out a successful rescue from depth.

I am making no such assumption, I would wonder why some would be doing that depth if they didn't at least have half an idea.

It is really simple, on your own you have no chance, with someone to assist you have half a chance, even if that is just a case of hitting your up button and getting you topside, bends can be treated more succesfully than drowning.

Where people get this idea the rescuer needs to blow off a load of stops is beyond me, you take care of yourself first and foremost, the rescue is secondary.

But go on, all I am seeing is opposition to my suggestions regarding tox, how would you suggest setting up your kit to mitigate to risk?

BTS
12-02-2013, 02:11 PM
I'd seriously consider taking someone up to the surface, making sure they were bouyant and going back down to decompress..


If you are playing it that way there is no need for you to go to the surface with them, just send them up.

Major Clanger
12-02-2013, 02:21 PM
If you are playing it that way there is no need for you to go to the surface with them, just send them up.

Killing them with kindness. End result still the same.

BTS
12-02-2013, 02:25 PM
Killing them with kindness. End result still the same.

How so, they are topside, the surface cover can treat them better than you can in water and better than you can yourself if you are toxing, a remote chance is better than no chance.

Anyway, as requested, what are your thoughts on how config can mitigate this example?

Major Clanger
12-02-2013, 02:52 PM
Anyway, as requested, what are your thoughts on how config can mitigate this example?

Well that was actually the question I asked in post 1 for the views of others that dive on their own but I'll give it a go...To focus just on an ox tox as it's your thing:

Identify the main causes of an ox tox - Set point too high, ppo2 too high, failure to monitor, failure to replace old cells, failure to replace damaged cells, faulty electronics etc

Mitigation - Set point kept within 1 to 1.3 range, dil set point at 1/1.1, good discipline and equipment to enable early detection (eg a hud where there wasn't one before), dodgy equipment replaced etc, be methodical with cells, methodical ppo2 checks, replace cells that have been in a flooded unit, good monitoring of levels and so on.

To be fair, prevention/avoidance doesn't need a great deal of additional stuff imo beyond the knowledge gained during mod 1 for the maintenance, checking and upkeep of units. From what I've read, ox tox incidents can often be traced back to either a user fuck up, complacency or kicking the arse out of it. Early detection of a rising ppo2 and quick response to it, is the most critical thing. So, as an example, loss of dil in a boom scenario may mean that the solo diver adds additional whips to his bailout in order to still be able to dil flush for high ppo2 or a flood as well as one for wing inflate. May mean they have a separate bottle of dil to offset losses...I've thought about running my wing on a different bottle for redundancy to preserve gas during the dive or in the event of a loss. So if I lose my dil cylinder, I can have the offboard plumbed in to the exhale lung to compensate and a small bottle for wing inflate. No need then to worry about taking feeds from a buddy.

BTS
12-02-2013, 03:48 PM
OK, so you have done all that and you still get a hit, what then?

Timw
12-02-2013, 03:56 PM
The commercial lot used to do bend and fix methods... out of the water, into a chamber

Done that. It's dodgy at best when your ascent is controlled.

Missed stops may not kill you but the barotrauma almost certainly will - it killed two people I knew in the last few years. Sending someone unconscious up alone from 20m+ has a very good chance of killing them.
Minimise the risk of tox by managing your ppo2, O2 exposure and CO2 exposure - all part of the training. How many tox events have you come across? I haven't seen any so far. I have seen plenty of other incidents where having the right kit and experience has made it a non event in real terms.
I dive with a lot of very competent divers but I'm not sure they could all lift an unconscious diver from 70m+ successfully. I'd prefer to have the mindset that I am on my own and be prepared to sort the problem out before it becomes life threatening. If I was skydiving, I wouldn't have someone there to hand me a spare parachute... It's not about having no options, it's about being prepared for the worst.

BTS
12-02-2013, 04:07 PM
Sending someone unconscious up alone from 20m+ has a very good chance of killing them.


Drowning has a 100% chance...

Sending them up unconscious might very well bend them, equally they might get treated quickly and survive unscathed. Drowning, on the other hand, has a pretty good chance of ending your days...

I agree with the need for a solo mindset and the determination to mitigate and spot issues before they become problems but equally I think the determined want seen in some people nowadays to dive exclusively solo is misguided. Diving solo within a team of at least two offers the best chance of surviving the vast majority of situations.

GLOC
12-02-2013, 04:28 PM
Paul, a good point about bending being survivable, but I think that Tim was talking about barotrauma rather than DCS per se.

Regards

BTS
12-02-2013, 04:30 PM
What barotrauma is likely to occur in an unconscious diver? Expand {pun intended} please...

GLOC
12-02-2013, 04:40 PM
At shallower depths, depending on which the casualty is up, the lungs as they will not be able to vent clearly?

Taking it to extreme, someone ascending from 60m in a couple of mins ending up with massive internal injuries which meant that no matter how much BLS was provided, they died.

Regards

BTS
12-02-2013, 04:59 PM
At shallower depths, depending on which the casualty is up, the lungs as they will not be able to vent clearly?

Taking it to extreme, someone ascending from 60m in a couple of mins ending up with massive internal injuries which meant that no matter how much BLS was provided, they died.

Regards

What mechanism prevents the lungs venting? I was under the impression you had to be concious to hold your breath and I accept that the tongue may block the airways, is there another reason I don't know off?

Either way, the odds of survival are increased compared to toxing alone at depth.

I chose toxing for this as I see no way a solo diver can get themselves home safely, it is the only example I can think of at the moment where survival pretty much 100% depends on someone intervening. So it boils down to guaranteed dead or slim chance of not being dead, I know the odds I prefer. If I am sent skywards and suffer a lung over expansion I will be no more dead than if I had toxed alone at sixty metres...

GLOC
12-02-2013, 05:02 PM
I agree, dead is dead, at least on the surface your family has a body.

The mechanism I am referring to is the expansion of gas in your lungs (if inverted) is likely (my guess) to be greater than the gas can escape downwards and out your throat/mouth before the lung tissues rupture.

Regards

BTS
12-02-2013, 05:11 PM
The mechanism I am referring to is the expansion of gas in your lungs (if inverted) is likely (my guess) to be greater than the gas can escape downwards and out your throat/mouth before the lung tissues rupture.

Regards

OK, seems reasonable but the odds of being upside down are what? the same as being in any other position? Without testing the theory i imagine a horizontal position either face up or face down is more likely isn't it?

Either way, again, the odds are more favourable than the alternative and this can only be achieved if somebody initiates the rescue, the scenario is beyond self rescue.

I am happy to accept that the tox situation is out there on its own and it is possible for a solo diver to get out of all other situations, I am also happy to accept it is a rare occurrence, my initial introduction of tox into the thread was simply to show that there are times when assistance is necessary. Solo diving seems to be the new buzz term, I have been known to drop in, happily, on my own from both shore and boat but wouldn't dismiss buddy or team diving completely in favour of solo diving. There are times I feel it is not the best option.

bottle maker
12-02-2013, 05:23 PM
Do not try to kid your selves that diving solo can be as safe as diving with a buddy. As the OP asked about technical dives I presume he means deeper and longer dive,s that do not allow you direct access the surface. I know of three CCR divers that would have not survived if it was not for the direct intervention of others. Two were assisted by there buddies deeper than 40 meters one was solo and it was only by pure chance a passing diver spotted him and set of the rescue process that ultimately saved him.

Yes you can add additional equipment to reduce the possibilities of you dying alone but your chances of surviving will be increased by having a buddy.

Yes I have dived alone I do it because I enjoy it not because I think it is safer.

Graham.

Major Clanger
12-02-2013, 05:29 PM
I know the odds I prefer. .

No problem with you doing what's right for you, likewise it needs to be accepted that others will do what's right for them. If that means they accept a higher level of risk then so be it, so long as that risk is calculated and the dive entered in to with eyes wide open and maximum preparation. The dangerous thing is intolerance and forcing a widely conducted activity underground. If we didn't accept varying levels of risk, we'd all be in the shallow end with a snorkel...

BTS
12-02-2013, 05:39 PM
If that means they accept a higher level of risk then so be it

People are free to endanger themselves however they wish but IMO the increase in risk must be balanced with the increase in reward....I don't see that it does when it comes to solo tec...

Major Clanger
12-02-2013, 05:40 PM
Do not try to kid your selves that diving solo can be as safe as diving with a buddy. .

Reminds me of one particular ccr diver I dived with who's inability was positively detrimental to a safe dive. How he passed mod 1 I've no idea. Like you, I dive solo when it suits me to because I also enjoy it, not because I believe it's safer and have intentionally avoided suggesting otherwise.

Major Clanger
12-02-2013, 05:45 PM
see that it does when it comes to solo tec...

Assuming the definition of technical diving is anything below 40 metres and a virtual overhead, the all encompassing definition is wide ranging from a few mins deco after a 40.1m dive, to a 100+m dive with a ridiculous TTS. Typically my tolerance of acceptability and enjoyment from diving solo is towards the lower end of the range. Hanging around too long on a bit of string is boring.

Timw
12-02-2013, 05:50 PM
OK, seems reasonable but the odds of being upside down are what? the same as being in any other position? Without testing the theory i imagine a horizontal position either face up or face down is more likely isn't it?

Either way, again, the odds are more favourable than the alternative and this can only be achieved if somebody initiates the rescue, the scenario is beyond self rescue.

I am happy to accept that the tox situation is out there on its own and it is possible for a solo diver to get out of all other situations, I am also happy to accept it is a rare occurrence, my initial introduction of tox into the thread was simply to show that there are times when assistance is necessary. Solo diving seems to be the new buzz term, I have been known to drop in, happily, on my own from both shore and boat but wouldn't dismiss buddy or team diving completely in favour of solo diving. There are times I feel it is not the best option.
In a drysuit the odds of a feet first ascent are much higher than any other orientation as the air is trapped in the suit. A head first rapid ascent is more likely to result in the casualty not getting to the surface as the neck seal can blow out and dump all the buoyancy. There is the same effect in the lungs - they over expand faster than they can vent as there is no conscious exhalation of gas. When upright, the head of an unconscious person tends to drop forward, obstructing the airway.

I agree about solo being the new buzz word. It isn't for everyone and there is quite a large latitude in the definition. I consider myself solo when I'm taking pictures, on a wreck in sight of 10 other divers, or just ascending alone, as well as when I choose to complete the whole dive solo.

I also agree that solo isn't always appropriate. I have a regular buddy for a lot of my dives but if I've grabbed a spot on a charter with people I don't know, I'd often rather dive on my own.
I've tried to set my kit up to manage most situations but there will be some I haven't thought of or are impractical. For example, I've decided not to get a high viz suit to mitigate against getting run over on the way back to the car in the dark.

dwhitlow
12-02-2013, 07:30 PM
Killing them with kindness. End result still the same.
Unless you can keep a sensible gas source in their mouth for the whole ascent drowning is certain. At the surface the options vary. Whether you go with ethem depends on personal choices...

Simon Mitchell gave an excellent presentatrion at Eurotek on the subject and you can read the paper here http://www.thediveforum.com/incidents-safety-information/1329-uhms-39-paper-unconscious-diver-recovery.html

Major Clanger
12-02-2013, 08:31 PM
Unless you can keep a sensible gas source in their mouth for the whole ascent drowning is certain.


This is largely why I concluded a deep rescue will probably not result in a positive outcome?

Excellent paper, referred others to it when first released.

Major Clanger
12-02-2013, 08:31 PM
dupe

Barrygoss
12-02-2013, 08:36 PM
So to answer to OP, the modifications to make to the breather would be:
A BOV
offboard access to LOTS of gas via the BOV, without having to remove it
a gag strap or FFM
A buddy to send you on the way ;)

B

I went for 3 out of those 4, and a large bite long reach mouthpiece (I didn't fancy the gag strap)

Major Clanger
12-02-2013, 08:45 PM
So to answer to OP, the modifications to make to the breather would be:
A BOV
offboard access to LOTS of gas via the BOV, without having to remove it
a gag strap or FFM
A buddy to send you on the way ;)

B

For this scenario the gag's looking increasingly appealing. I think someone somewhere was investigating the effectiveness of them. So the toxing solo diver needs to wear a gag, hit the up button and enjoy the ride ;)

Barrygoss
12-02-2013, 08:48 PM
For this scenario the gag's looking increasingly appealing.

fnar fnar

B

dwhitlow
12-02-2013, 08:50 PM
I didn't fancy the gag strap
I find the gag strap quite good as it means the mothpiece stays where I need it without any effort on my part.

Give it a try, you might surprised - I use the RB02/12 AP Diving Headstrap.

Major Clanger
12-02-2013, 08:50 PM
I'll wear it down at Plymouth, just for you. Want to know my room number


:coward:

Major Clanger
12-02-2013, 08:52 PM
I find the gag strap quite good as it means the mothpiece stays where I need it without any effort on my part.

Give it a try, you might surprised - I use the RB02/12 AP Diving Headstrap.

I have that headstrap Dave but have yet to try it.

GLOC
12-02-2013, 08:55 PM
For this scenario the gag's looking increasingly appealing. I think someone somewhere was investigating the effectiveness of them.
It was one of the consensus positions from RF3.0 but I am not sure there was anyone who picked up the research task of understanding the effectiveness in sustaining life of an unconscious diver.

Regards

dwhitlow
12-02-2013, 08:57 PM
I have that headstrap Dave but have yet to try it.Cheap, simpler and effective.
I've found it easier to let it sit at the back of the neck. In that position keeps BOV in place and keeps strap clear of mask strap.
I'm still alive so it must be working :grin:

Major Clanger
12-02-2013, 08:59 PM
I'm still alive so it must be working :grin:

Let me know if that situation changes and I'll put it on ebay :)

Barrygoss
12-02-2013, 09:01 PM
Cheap, simpler and effective.
I've found it easier to let it sit at the back of the neck. In that position keeps BOV in place and keeps strap clear of mask strap.
I'm still alive so it must be working :grin:

but if you do TOX, your buddy has to wait with you until you're post-ictal before sending you up, otherwise you will experience barotrauma
B

Major Clanger
12-02-2013, 09:02 PM
It was one of the consensus positions from RF3.0 but I am not sure there was anyone who picked up the research task of understanding the effectiveness in sustaining life of an unconscious diver.

Regards

I can see how it may make the workload of a rescuer easier during a ccr cbl.

GLOC
12-02-2013, 09:04 PM
but if you do TOX, your buddy has to wait with you until you're post-ictal before sending you up, otherwise you will experience barotrauma
B

Ahhh, I am sure this was covered recently too. Maybe in that UHMS paper. I'll see what I can find.

Apologies:


It follows from the above that the committee’s determination
is as follows: If a compressed-gas diver is
discovered in the clonic phase of a seizure at depth and
the regulator is not in the mouth the diver should be
retrieved to the surface without delay. If the regulator is
in the mouth, then every attempt should be made to hold
it in place while sealing the lips around the mouthpiece;
surfacing should be delayed until the seizure has
resolved.
This recognizes the committee’s perception that
without the regulator in place, drowning on resumption
of breathing probably represents the greatest threat
to life, and with the regulator held in place, pulmonary
barotrauma during an ascent with a closed glottis
becomes the greater concern. p1102

Regards

dwhitlow
12-02-2013, 09:04 PM
but if you do TOX, your buddy has to wait with you until you're post-ictal before sending you up, otherwise you will experience barotrauma
B
The research presented by Simon Mitchell at Euroteck showed that might not be the case (they abused pigs as I recall) and an immediate ascent is an option.

Major Clanger
12-02-2013, 09:07 PM
Ahhh, I am sure this was covered recently too. Maybe in that UHMS paper. I'll see what I can find.

Apologies:

p1102

Regards

Page 1102.


Ack, beat me too it.

Barrygoss
12-02-2013, 09:07 PM
Ahhh, I am sure this was covered recently too. Maybe in that UHMS paper. I'll see what I can find but I am sure that this isn't the case. 2 ticks....

Regards

That would be interesting, I know in the Tonic phase it's dangerous (spasming respiratory muscles and throat mean no ventilation) and clonic is convulsions (so possible but you're trying to lift a convulsing body)

Still it needs a buddy to wait for a bit before sending you ;)

B

Baron015
12-02-2013, 10:36 PM
I haven't made any mods to my JJ yet and I've had it a while now.

But with all this in mind I've ordered a Shrimp BOV (unit came with DSV only due to temporary CE snafu).

And I think I will try out a gag strap to see how I get on. But I might call it a mouthpiece retaining strap, when in polite company.

I also have whips on all my bailouts to plug into the MAV if I need to.

I use separate suit inflate for redundant buoyancy option.

Maybe I should do more, since I do the occasional solo dive if I don't know anyone on the boat. But mainly preparation and avoidance, not doing significant penetration when solo, and making sure I don't exceed my own bail out limits (based on normal SAC rather than emergency CO2 hit SAC).

I will also bring my own drop tank, ready prepared with buoy and line, of spare 80% and discuss with skipper deployment arrangements, if TTS is going to be long and I am solo.

Tb.

Major Clanger
13-02-2013, 06:34 AM
and making sure I don't exceed my own bail out limits (based on normal SAC rather than emergency CO2 hit SAC).

I will also bring my own drop tank, ready prepared with buoy and line, of spare 80% and discuss with skipper deployment arrangements, if TTS is going to be long and I am solo.

Tb.

For bailout planning I'm looking at double my SAC and a gf of 90/90 for faster ascent.

As mentioned elsewhere, the boat may be considered part of the team and also carry a yellow and have a drop tank of 80, subject to skipper's approval.

Not every bailout scenario is as a result of near death, full flood for example, so ascent can still be reasonably controlled in these events on your own.

Stonybonytony
14-02-2013, 01:49 AM
What condition is a diver in following tox? Once the seizure has finished, a diver in a ffm will recommence breathing, are they likely to be unconscious, or in no fit state to self rescue?

If the high ppo2 situation has persisted, I suppose it us likely that they would have to rectify this pretty sharp ish or they will tox again. If it was transient ( and there was a bottom or wreck to stop them sinking into the depths) and the diver returns to consciousness, is it survivable?

I know enough about tox to fear it, and to try to avoid it, but have never experienced it or known anyone who has. But it does make me think maybe I should be leaning towards a ffm, or at least a gag strap as discussed.

Stonybonytony
14-02-2013, 01:50 AM
What condition is a diver in following tox? Once the seizure has finished, a diver in a ffm will recommence breathing, are they likely to be unconscious, or in no fit state to self rescue?

If the high ppo2 situation has persisted, I suppose it us likely that they would have to rectify this pretty sharp ish or they will tox again. If it was transient ( and there was a bottom or wreck to stop them sinking into the depths) and the diver returns to consciousness, is it survivable?

I know enough about tox to fear it, and to try to avoid it, but have never experienced it or known anyone who has. But it does make me think maybe I should be leaning towards a ffm, or at least a gag strap as discussed.

colinicky
14-02-2013, 04:36 AM
In a drysuit the odds of a feet first ascent are much higher than any other orientation as the air is trapped in the suit. A head first rapid ascent is more likely to result in the casualty not getting to the surface as the neck seal can blow out and dump all the buoyancy. There is the same effect in the lungs - they over expand faster than they can vent as there is no conscious exhalation of gas. When upright, the head of an unconscious person tends to drop forward, obstructing the airway.


I agree a dry suit makes a feet first ascent more likely except that you have wing which will be expanding & you also have a set of counter lungs expanding as well which may help to counter act the feet first effect of the dry suit ? Personally I would open their dry suit valve dump fully before sending them up .
Likewise if the person is using a gag strap then the loop volume buoyancy may be enough to keep the head in a more upright position & maintain an airway ?


I have dived solo for all dives in the last 4 years except 2.
I moved from an inspiration vision to a rEvo because it has 2 separate scrubber cartridges to help mitigate against a CO2 hit, my feeling being if I badly pack both scrubbers then I deserve everything that happens! I am in the process of fitting a BOV to give me immediate access to oc gas for any reason . I run whips on every cylinder that can be plugged into the mav & regularly practice changing them, regularly clean & grease the fittings.
My next major step is a side mount bailout ccr after realising that I can not carry enough gas for a real oh shit moment, yes I had been kidding myself for years that I could get out on what I carried .
I dive solo because I enjoy it, I do everything I can to mitigate the riskin diving solo but I am under no illusions that it is safer. Having said that on my deepest dive that I actually had a buddy we got to the bottom at 82m only for me to discover that I was not getting any O2 feeding the unit & my buddy could not realise from my po2 was dropping when I was holding the display in front of them & making signs that my O2 was not working ie point at display & O2 gauge & give ooa sign. So I signalled that I was ascending & they decided to stay on the bottom ! This was somebody who I had previously been on plenty of boats with & considered a good diver.

Major Clanger
14-02-2013, 07:02 AM
... for me to discover that I was not getting any O2 feeding the unit & my buddy could not realise from my po2 was dropping when I was holding the display in front of them & making signs that my O2 was not working ie point at display & O2 gauge & give ooa sign. So I signalled that I was ascending & they decided to stay on the bottom ! This was somebody who I had previously been on plenty of boats with & considered a good diver.

A good example of the human link being the weakest part of the chain. What was the reason for no o2 feed - empty cylinder, turned off, blockage, equip failure or other?

colinicky
14-02-2013, 06:19 PM
A good example of the human link being the weakest part of the chain. What was the reason for no o2 feed - empty cylinder, turned off, blockage, equip failure or other?

Human Error :doh: I forgot that my absolute pressure first stage was set to 8 bar so when I hit 70 ish metres it stopped flowing :( I did work out why before I left the bottom so no real drama.