NWD
I'm fairly sure you didn't mean for this to sound this way but its almost like you're saying because you guys are volunteer you don't need ponys
Pony tanks/secondary air supply
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NWD
I'm fairly sure you didn't mean for this to sound this way but its almost like you're saying because you guys are volunteer you don't need ponys
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I think if his team is like ours, it is because being a volunteer organization our equipment requirements are basic scuba setups: BC, wetsuit/drysuit, regs, mask, gloves, hood, boots, fins, weights, and guages.
For me, the pony is a requirement since even if I'm on the end of a line, I am solo down there. When I'm huffing and puffing on the end of that line, if something happens to my primary air supply, I only have seconds to correct that situation. I practice switching to the pony reg on every dive just to try to make it an automatic process in case I need it in an emergency. But I'm the only one that dives with one. I'm not sure but I feel that other team members feel ponys are another potential source of entanglement. I always think that if I get entangled, I have time to get untangled. And if I can't untangle, I can dump my BC, pull my pony and take it to the surface. I would like to hear why other people may not use ponies.
For me, the pony is a requirement since even if I'm on the end of a line, I am solo down there. When I'm huffing and puffing on the end of that line, if something happens to my primary air supply, I only have seconds to correct that situation. I practice switching to the pony reg on every dive just to try to make it an automatic process in case I need it in an emergency. But I'm the only one that dives with one. I'm not sure but I feel that other team members feel ponys are another potential source of entanglement. I always think that if I get entangled, I have time to get untangled. And if I can't untangle, I can dump my BC, pull my pony and take it to the surface. I would like to hear why other people may not use ponies.
What do you carry when you have a ceiling, physical or glass?
Hi Grid
I think you're on the right track. Good for you!
Hopefully you can convince the rest of your team the importance of using a pony.
I know I wouldn't be very happy if I knew my back-up diver didn't have a pony - that is basically MY air if I get trapped and not immediately freed!
Try to explain this to them:
In the situation where I'm entangled to the bottom AND low on air a backup without a bailout to pass off is useless - he can't go and get tools/help because if he does the trapped/OOA guy dies and if he can't immediately free trapped/OOA guy they BOTH run out of air - he is essentially "tied" to the trapped guy.
** entanglements are the very reason WHY we are using ponys!**
Entanglements in themselves will never kill us - they are an annoyance. OOA will kill us (and panic but if we have a good procedure and the team is practiced there should be no panic). If I know my back-up can get me air I can still survive trapped on the bottom for hours until I can be freed. If I loose my one and only air supply I've got mere seconds of life - the backup will find me long gone whether he has a pony or not.
Remember also that realizing your entangled is most likely to occur when you attempt to resurface at the end of the dive. When do we have the least amount of air in our tank? (great time to get tangled up...)
We often hear that guys don't want to use ponys because of entanglements but do a little role playing such as above. What is interesting sometimes is the same guys will say this yet when they are geared up they got the big 007 leg knife attached to their calf
Ponys if carried correctly should not cause anymore entanglement risk than your regular tank does. They should be back mounted and out of the search area/entanglement zone. Some that are mounted within the BCD have less entanglement risk than your mask would. If they're slung as per a tech diver, yes - this is a big entanglement nightmare - don't do PSD in this fashion
Peter
This may answer your question as well as we are prepared to be in an overhead "like" situation at any time with the threat of entanglements - ie the diver cannot immediately surface without aid.
Basically, limited depth, distance and time are all factored in with at least 1 back-up diver (ideally 2) and contengency bottles at the ready. Even so overhead diving is considered advanced and may not be conducted by allot of teams -- SSA may be better suited for things like docks, overturned boats etc
hope this is clear
mark
I think you're on the right track. Good for you!
Hopefully you can convince the rest of your team the importance of using a pony.
I know I wouldn't be very happy if I knew my back-up diver didn't have a pony - that is basically MY air if I get trapped and not immediately freed!
Try to explain this to them:
In the situation where I'm entangled to the bottom AND low on air a backup without a bailout to pass off is useless - he can't go and get tools/help because if he does the trapped/OOA guy dies and if he can't immediately free trapped/OOA guy they BOTH run out of air - he is essentially "tied" to the trapped guy.
** entanglements are the very reason WHY we are using ponys!**
Entanglements in themselves will never kill us - they are an annoyance. OOA will kill us (and panic but if we have a good procedure and the team is practiced there should be no panic). If I know my back-up can get me air I can still survive trapped on the bottom for hours until I can be freed. If I loose my one and only air supply I've got mere seconds of life - the backup will find me long gone whether he has a pony or not.
Remember also that realizing your entangled is most likely to occur when you attempt to resurface at the end of the dive. When do we have the least amount of air in our tank? (great time to get tangled up...)
We often hear that guys don't want to use ponys because of entanglements but do a little role playing such as above. What is interesting sometimes is the same guys will say this yet when they are geared up they got the big 007 leg knife attached to their calf
Ponys if carried correctly should not cause anymore entanglement risk than your regular tank does. They should be back mounted and out of the search area/entanglement zone. Some that are mounted within the BCD have less entanglement risk than your mask would. If they're slung as per a tech diver, yes - this is a big entanglement nightmare - don't do PSD in this fashion
Peter
This may answer your question as well as we are prepared to be in an overhead "like" situation at any time with the threat of entanglements - ie the diver cannot immediately surface without aid.
Basically, limited depth, distance and time are all factored in with at least 1 back-up diver (ideally 2) and contengency bottles at the ready. Even so overhead diving is considered advanced and may not be conducted by allot of teams -- SSA may be better suited for things like docks, overturned boats etc
hope this is clear
mark
The PSD diving I've done has either been with just a single tank when I was in shallow water with no especial risk of entanglement, or with a twinset when there was a greater risk. A pony would do in relatively shallow water.
One thing that most people don't realise is how their consumption sky-rockets when they're working, and especially when they're stressed. Unfortunately my IANTD PSD manual was stolen so i can't refer to it, but I seem to remember air consumption increasing by up to an order of magnitude, or even more. Can any diver with his manual please clarify?
One thing that most people don't realise is how their consumption sky-rockets when they're working, and especially when they're stressed. Unfortunately my IANTD PSD manual was stolen so i can't refer to it, but I seem to remember air consumption increasing by up to an order of magnitude, or even more. Can any diver with his manual please clarify?
Sorry I'm not familiar with this IANTD book but you bring up a very important point. Knowing a divers SAC is very important as he probably can't read his SPG (a waste of time even if he could). This becomes one of the roles of the tender; he will get a "feel" for how his diver is behaving and find out from the diver what his common SAC rates are and your right they do vary (night, real op, training, cold/ice etc). the tender then can verify throughout the dive whether the diver's SAC is too high by counting breaths per minute. If he's too high (for any reason) the diver should be replaced.
Essentially end the problem before it gets out of hand. Even a working PSD shouldn't be breathing more than 1cuft/min. Anywhere from .5 to .8 is probably OK for most. Stress shouldn't be a HUGE deal if the team is well practiced but of course it will have some affect
Knowing your recreational SAC is of no value whatsoever. Many amateur "PSD" divers have drowned because they had no idea their air consumption would be 7 or more times its normal rate.
What PSD manuals are you aware of?
What PSD manuals are you aware of?
Where did I say "recreational SAC"? A person determines their SAC over the course of many dives in different situations - current, ice, blackwater, weeds, clear water etc be it rescues, recoveries or training. My SAC will be lower during a mid-water good vis dive compared to a blackwater search through weeds but as a diver I should know my SAC for any environment I may encounter. If we train properly we can do pretty much the same work effort as we normally have in a real scenario. The difference between real and training should be very small.
The tender KNOWS how much air the diver comes back on deck with usually within 100psi because he is tracking it - without keeping track of how much air the diver is using, you're right, they run the risk of being OOA.
We often loose sight on how valueable the tender really is because he essentially is controlling everything about the dive
7 times!! If someone is breathing 7 times their normal rate they have no business being there. Even double their regular breathing rate may be enough to cause a blackout as CO2 will knock them out before too long...
The only PSD manuals I know of are of the big 4 PSD agencies - DRI, LGS, PSDA, ERDi. Maybe you're using something different outside of North America? I'd be interested in having a look at it though if you have a link or something
IANTD is American, and I used to have their manual. It cited several case histories of fatalities and what led up to them, and yes, breathing rate absolutely rocketed in several of these cases and was the cause of the deaths. I believe all were in the USA.
Gotcha, Maybe Blades would know more about IANTD. Could they be out of the PSD business now? Procedures have definately evolved over even the past 10yrs.
As I said I wouldn't accept a diver with an abnormally high breathing rate (over 20-24 BPM). Instead I would explore what the cause of the spike in breathing would be - this is the smoking gun not the breathing itself. Could be the diver unskilled, poor procedures or in over his head etc
nice discussion although I think we de-railed somewhat as to what grid wanted to talk about - who uses pony bottles
As I said I wouldn't accept a diver with an abnormally high breathing rate (over 20-24 BPM). Instead I would explore what the cause of the spike in breathing would be - this is the smoking gun not the breathing itself. Could be the diver unskilled, poor procedures or in over his head etc
nice discussion although I think we de-railed somewhat as to what grid wanted to talk about - who uses pony bottles
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