View Full Version : Lifejacket for snorkelling?
Toblerone
29-06-2011, 13:27
I understand that BSAC (perhaps alone among training organisations) recommends the wearing of a CO2 inflatable life jacket. I currently wear a Mares snorkel jacket which I find very useful in that it allows me to add a bit more buoyancy when sorting out a cramp etc. (we normally don't bother with a float if close to shore in areas where boat traffic is rare - and trust me it is rare!) or to enable me to add a bit more weight when I want to go neutral a couple of metres down.
I like the look of and added security of a manually actuated CO2 LJ, but these things are worn stowed away and presumably you can't manually add or expel air from them without depolying them first - they're either fully deployed or not. I really want to retain that facility. I also have an old Buddy ABLJ which I contacted the manufacturer about getting refurbished, but it really is too bulky/draggy to be a viable.
What models are folk snorkelling OW with BSAC actually using and what are their strengths and weaknesses?
Many thanks
Chris
HU1 Diver
29-06-2011, 14:07
These appear to be quite popular. Obviously there are other makes, models and vendors.
http://cgi.ebay.co.uk/SEAC-SUB-Snorkelling-jacket-VEST-ADULT-38-48-/270552739311?pt=UK_SportingGoods_MasksSnorkels_Fli ppers_SM&hash=item3efe332def
Toblerone
29-06-2011, 19:49
These appear to be quite popular. Obviously there are other makes, models and vendors.
http://cgi.ebay.co.uk/SEAC-SUB-Snorkelling-jacket-VEST-ADULT-38-48-/270552739311?pt=UK_SportingGoods_MasksSnorkels_Fli ppers_SM&hash=item3efe332def
No. I aready have two of the Mares equivalent of that. It lacks CO2 inflation and actual certified life jacket buoyancy and keeping your face out of the water capability - that's what I'm looking for, but retaining the ability to use it to make minor buoyancy adjustments. I meant something more like this:
http://www.ctcmarineandleisure.co.uk/acatalog/Pilot_Inflatable_Lifejacket.html
Yak Diver
05-07-2011, 21:29
you can't get them in this country, I bought mine from USA like this one
http://www.scubaduba.com/scuba-gear/Sea_Elite_Snorkel_Vest_wCO2.html
http://northeastscubasupply.com/store/snorkeling-items/snorkeling-vests/aqualung-sport-snorkeling-vest-co2-inflation-style/prod_2955.html
Toblerone
06-07-2011, 15:29
you can't get them in this country, I bought mine from USA like this one
http://www.scubaduba.com/scuba-gear/Sea_Elite_Snorkel_Vest_wCO2.html
http://northeastscubasupply.com/store/snorkeling-items/snorkeling-vests/aqualung-sport-snorkeling-vest-co2-inflation-style/prod_2955.html
That is exactly what I was looking for. Thank you Yak!
Aqua lung do a similar product called a rescue swimmers vest. These can be orally inflated BCD style (corrigated hose with mouth piece/dump valve) and have either one or two manually fired CO2 cartridges. They also have a strobe mounting point and a pocket designed for a spare air/HABD bottle.
ChristianG
11-07-2011, 14:25
a pocket designed for a spare air/HABD bottle.
Did someone mention the Spare Death - I mean Air?
Did someone mention the Spare Death - I mean Air?
Using a spare death snorkelling! That would introduce new and interesting ways to kill you that it does not normally offer
Yes. Not saying it's suitable but that it's a feature to carry one on the jacket I mentioned. Primarily used by US Coast guard and marine safety swimmers I think. Presumably they get issue a HABD/sea-air etc incase the chopper goes in the drink. The pocket can be used to carry other kit (otter box of woodbines?) so might be useful.
Compared to BCD's a lot of the life jackets and snorkelling vests don't seem to have a way to stow any gear. It would be nice to have somewhere fairly streamined to carry a torch, strobe, slate, laminated copy of Mr Ben the Diver etc. There are places I don't bother with an SMB/float.
I say this in the sense no-one seems to commercially make this. I tend to tinker and modify a lot of my stuff so I have a snorkelling vest/collar that's got pouches.
Yes it is just a snazzy ABLJ really......
Toblerone
12-07-2011, 10:04
Hi Guys. I'm not sure what additional harm a SpareAir (or whatever the one with the separate 2nd stage the USN and USCG now use is called) would do to a snorkeller (and yes, I do know my gas laws). Someone advocated one for abalone collecting freedivers of California who can get entangled in kelp and drown. However, if you had one on you the Fish Game and Wildlife people would be straight onto you as using SCUBA to collect abalone is a no-no.
The lack of pockets on snorkelling jackets and harnesses is particularly annoying. What I currently do is have a SeacSub neoprene non QD neoprene weight harness with 5kg of weights in it (plus 2x0.5kg ankle weights and a variable amount on a Marseille belt). I have cable tied a Seatec dagger to the left shoulder (I have another on my belt) and also clip a Cetacea coiled bungee for my camera to one of the cable ties - this is the type you can shorten for transit by clipping it together. On the other side I have a torch on a Beaver extender reel attached by velcro.
Over the top of the non QD weight harness I wear a Mares snorkel jacket that I intend to replace with an equivalent with CO2 inflation back-up. I have attached a whistle to the oral inflator. I keep thinking of switching to a QD weight harness, but the neoprene one is very comfortable and 5kg is a less than half the weight I normally wear (which varies according to intended depth and conditions) as I have a two-piece 7mm Elios spearfishing suit which is pretty buoyant. I also have a Scapa Scuba 7mm neoprene drysuit on order for protracted static filming sessions at the surface.
Hi Guys. I'm not sure what additional harm a SpareAir would do to a snorkeller (and yes, I do know my gas laws).
Snorkellers habitually hold their breath.
You are only going to use the spare death in a stressful situation.
When in a stressful situation the human brain reverts to instinct/habit rather than thinking things through.
Breathing compressed gas at depth and holding your breath on the way up will kill you
The important point is 3; that cannot be avoided.
Toblerone
12-07-2011, 16:08
Snorkellers habitually hold their breath.
You are only going to use the spare death in a stressful situation.
When in a stressful situation the human brain reverts to instinct/habit rather than thinking things through.
Breathing compressed gas at depth and holding your breath on the way up will kill you
The important point is 3; that cannot be avoided.
Hi Pete.
1. Many snorkellers are also SCUBA divers - is there evidence out there that those that also snorkel have a higher rate of PE/barotrauma?
2. True, but also true of the knife (or knives) you'll use to cut yourself free of entanglement or the lifejacket you'll inflate at the surface or a myriad of other safety related items you'll need to use in a variety of different situations. As I understand it, if you work offshore in the EU you must train on helicopter underwater escape techniques using either SpareAir (or something analagous to it) or a rebreather. I'm not aware of the stats, but I have read an evaluation that said the tiny number of embolisms etc. in training was considered acceptable vs the probability of ditching in a helicopter. I would have hoped offshore safety had improved since Piper Alpha, but I'm sure there are a lot of members here more highly qualified than me to comment on that.
3. True, but also true of SCUBA divers and presumably particularly true of novice ones.
4. Falls under 'I know my gas laws'.
I wasn't for one minute advocating that snorkellers, unversed in SCUBA, should start packing SpareAirs or similar. The impression I get (and I could be wrong) is that the abalone harvesting crowd are mostly also SCUBA divers but aren't allowed it specifically for abalone harvesting (to avoid over-exploitation of the resource).
Hi Pete.
1. Many snorkellers are also SCUBA divers - is there evidence out there that those that also snorkel have a higher rate of PE/barotrauma?
2. True, but also true of the knife (or knives) you'll use to cut yourself free of entanglement or the lifejacket you'll inflate at the surface or a myriad of other safety related items you'll need to use in a variety of different situations. As I understand it, if you work offshore in the EU you must train on helicopter underwater escape techniques using either SpareAir (or something analagous to it) or a rebreather. I'm not aware of the stats, but I have read an evaluation that said the tiny number of embolisms etc. in training was considered acceptable vs the probability of ditching in a helicopter. I would have hoped offshore safety had improved since Piper Alpha, but I'm sure there are a lot of members here more highly qualified than me to comment on that.
3. True, but also true of SCUBA divers and presumably particularly true of novice ones.
4. Falls under 'I know my gas laws'.
I wasn't for one minute advocating that snorkellers, unversed in SCUBA, should start packing SpareAirs or similar. The impression I get (and I could be wrong) is that the abalone harvesting crowd are mostly also SCUBA divers but aren't allowed it specifically for abalone harvesting (to avoid over-exploitation of the resource).
Points 1, 2 & 3: We need to think about what triggers a particular learned response. When I am in a car if someone steps out in front of me I go for the middle pedal, when I am on the bike I go for the right handle bar. There is no thought process in which of these to do it is instinctive. I would suggest that carrying a tonne of kit would trigger the scuba instinct and the lack of kit the snorkel instinct.
My concern is putting someone in a situation where they are constantly having to do one thing (hold their breath) and then at a moment of stress expect them to do the exact opposite will lead to the wrong response in an unacceptable number of cases. To use my example above, what would happen if when I was in the car if I had to remember to only use a hand operated brake if someone ran out in front of me and using the middle pedal would cause the car to accelerate?
4. I know, you said. However this is a public thread being read by others so for completeness it is important to ensure that the complete picture is given so that anyone contemplating using a spare death goes in with all the facts. This is particularly important for non divers as they may think "one of them spare air thingies will let me stay down longer without all the hassle of scuba kit".
Toblerone
12-07-2011, 16:38
Pete. All good points and well taken. I hadn't considered the effect of the weight of kit you carry SCUBA diving playing a part in the conditioned response. [late edit!]I'd still be intrigued to hear an answer (from anyone) on point 1. though.[/late edit]
ChristianG
12-07-2011, 16:59
1. Many snorkellers are also SCUBA divers - is there evidence out there that those that also snorkel have a higher rate of PE/barotrauma?
I have no data, empirical or otherwise, to give you. I also doubt that there is any - after all, a lungful of air on the way down is exactly similar to that same lungful of air on the way up - save for some depletion of the O2 content of it. It is hardly likely that anyone has done any specific studies of such an arcane subject which doesn't really have any value, at least from a scholarly PoV.
Toblerone
12-07-2011, 21:44
Sorry Christian, I meant the rate of PE in divers who don't snorkel recreationally vs those that do, when they both SCUBA dive. There has been very little research on the subject. My diving doctor pointed out that there have been cases of PE in freediving as part of our discussion, but cases not involving glossopharyngeal insufflation ('packing') are, as I understand it, very rare indeed. I can think of one that happened on a dynamic horizontal apnea run in a pool, but even that may have involved packing. On the other hand, as I'm sure you're aware freedivers can get DCS from dissolved nitrogen that they build up cumulatively on frequent deep dives.
[3]When in a stressful situation the human brain reverts to instinct/habit rather than thinking things through.
The important point is 3; that cannot be avoided.
In regards to point 3 this can be overcome with training. In terms of the HABD bottles they were designed to be used in a highly stressful situation - specifically aircraft crashing into water from low level/high speed with little time to prepare.
US Marines (for example) have the a spare air type device fitted to their kit, which is very heavy/bulky, when carrying out over water/littoral ops. I think they were introduced along with quick releasable body armour after a fatal accident involving a V-22 Osprey ditching.
Purely as an aside isn'tthere postmortem evidence of DCS in some deep diving marine mammals?
I'd also agree that data about PE/barotrauma in snorkelling divers is likely to be very limited. Realisticlly I think it may not be an issue for most when snorkelling. My old supervisor had a rule not to dive on scuba/SS after having been skindiving or spearfishing 12hrs before hand. However when in situation allowed most of my team would do so, 10-15m max depth over the course of an hour after diving.
Toblerone
13-07-2011, 12:44
My old supervisor had a rule not to dive on scuba/SS after having been skindiving or spearfishing 12hrs before hand. However when in situation allowed most of my team would do so, 10-15m max depth over the course of an hour after diving.
Hi Andy. I think that would have been due to the potential for DCS rather than PE/barotrauma.
The USMC have had a lot of issues with old, clapped out CH-46 helos crashing - that too may have driven the change. A friend of mine was in an AAV-7 (a big amphibious APC) that sank because someone neglected to put the passenger compartment drain plug back in at service. They had had to train for that eventuality and all escaped successfully. Presumably they issue those breathing sets and QD armour to AAV-7 passengers and crews too now.
I do accept Pete's point about the same person having two sets of conditioned reflexes with two methods of diving and equipment sets (his car vs bicycle analogy), but I do think it can largely, if not entirely be overcome by training. That said, I've never done it. On the other hand the 'it's too much to expect someone to remember to do that in a real life situation' argument has been used against smoke hoods on aircraft for years although there is a very strong argument that they would save passengers' lives in many otherwise survivable crash scenarios in civil aviation.
To get back on the Jacket front I am tempted to make something just for my self. A bladder from a wing with oral inflation and dump valve, fit this inside a simple waist coat with side pockets for kit. Slots in the jacket would then allow a standard manualy fired LJ to be worn and also act as the harness. Self adhesive velcro on the under side of the LJ could make the join between the two more secure but still allow the LJ to be used on it's own.
This would give you head up support if the jacket is fired, and head down support for swimming if the small wing is used.
Alternatively a direct replacement for the LJ harness incorperating pockets wouldn't be to hard to sew up as this wouldn't include the wing function. Currently I was thinking of using a 150N crewsaver or similar jacket I have mostly used.
Weight is carried on a rubber cressi belt (not Marseilles type) with 2kg for shortie and going up for other suits. I have never used a weight harness but I have been looking at the idea.
Toblerone
13-07-2011, 12:55
My old supervisor had a rule not to dive on scuba/SS after having been skindiving or spearfishing 12hrs before hand. However when in situation allowed most of my team would do so, 10-15m max depth over the course of an hour after diving.
Hi Andy. I think that would have been due to the potential for DCS rather than PE/barotrauma.
The USMC have had a lot of issues with old, clapped out CH-46 helos crashing - that too may have driven the change. A friend of mine was in an AAV-7 (a big amphibious APC) that sank because someone neglected to put the passenger compartment drain plug back in at service. They had had to train for that eventuality and all escaped successfully. Presumably they issue those breathing sets and QD armour to AAV-7 passengers and crews too now.
I do accept Pete's point about the same person having two sets of conditioned reflexes with two methods of diving and equipment sets (his car vs bicycle analogy), but I do think it can largely, if not entirely be overcome by training. That said, I've never done it. On the other hand the 'it's too much to expect someone to remember to do that in a real life situation' argument has been used against smoke hoods on aircraft for years although there is a very strong argument that they would save passengers' lives in many otherwise survivable crash scenarios in civil aviation.
ChristianG - you raise some good points.
ChrisWerb - I largely agree with you.
Sorry my browser is chopping my posts and showing things out of order. I appologise if I my responses seem confused (.com)
What models are folk snorkelling OW with BSAC actually using and what are their strengths and weaknesses?
Many thanks
Chris
I have got the SP from my club Equipment Officer - it's a snorkelling specific branch. 150N manual fired Crewasver brand are the kit they use.
ChristianG
17-07-2011, 12:13
May I, somewhat, Shanghai this thread?
Back in the days when I was a snorkeller we were, pretty well all of us few (note please how I said that), snorkeller/spearos and in a decidedly tropical environment, IOW, keeping warm was not the issue, keeping the sun off our backs/the backs of our legs was the issue. Particularly when we went into the water north of Colombo Harbour pretty well at daybreak and followed the (slight) prevailing current south until, having crossed the harbour entrance itself (a rather "dodgy" exercise oftentimes skipping around the entering/leaving freighters/liners) we ended up at the Colombo Swimming Club and came ashore. That little trip was usually sunrise to sunset and if we shot a fish we threaded it by the gills on a strong string with very blunt needle attached which was around our waists. Sharks? What sharks? We were lucky to see one.
Now that's in what we euphemistically call "the Far East" and, I suppose, it has little to do with UK snorkelling. Nevertheless, if you go back to those "far off" times I am sure that there was no such thing in the UK as a "snorkelling jacket", or whatever, in fact the BCD, by whatever name, hadn't yet been "invented" (it wasn't, as many would know it was originally a straight copy of the aircraft type "survival jacket" that, today, we all know and love).
Hi Andy. I think that would have been due to the potential for DCS rather than PE/barotrauma.
Yeah. I kinda was thinking aloud when I posted it. My old super is a bit of a renaissance man in diving. Ran the local chamber as LST and dealt with lots of incidents first hand. He developed some continuos gas blending systems and was involved (I believe with Comex) in testing Heliox treatment tables for bends, he was very anti table 5, 6A, 6 treatments. Anyway he is the sort of guy who might have data/experience regarding barotrauma with snorkelling divers.
He is based in South Africa and there's a high proportion of spearo's amongst divers.
ChrisG, now you say it the ancestry seems obvious, never noticed, doh. Free snorkelling vest everytime I fly.
Toblerone
21-07-2011, 13:15
I have got the SP from my club Equipment Officer - it's a snorkelling specific branch. 150N manual fired Crewasver brand are the kit they use.
Thank you Andy - that was the information I was looking for.
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