Have to agree with no wetsuits for deep dives come on!!! Had my wetsuit on plenty dives beyond 180fsw with no problems. But then again the water temp yesterday was 87F!!
Self-propagating negative bouyancy
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Dryglove
Contributor
At what depth would a wetsuit compress to its max and no longer be affected by the pressure as it is compressed to its max. Lets just use a 7mm as an example.
The reason i am asking if a wetsuit is fully compressed at lets say 90ft what difference would it make if you used at 150ft if it is already fully compressed at 90ft. It shouldnt affect your buoyancy a whole lot more.
I dive a trilam drysuit so i dont have to deal with all the wetsuit isues with losing buoyancy.
The reason i am asking if a wetsuit is fully compressed at lets say 90ft what difference would it make if you used at 150ft if it is already fully compressed at 90ft. It shouldnt affect your buoyancy a whole lot more.
I dive a trilam drysuit so i dont have to deal with all the wetsuit isues with losing buoyancy.
Scuba_Vixen
Guest
once I get past about 60', and it's not much of an issue after 40 or 50...and that's a fairly new 7mil SP S-Tek. I have a custom Body Glove in 5mil, and that's not noticeably different much past 30 to 40. Even on reef dives, both are just Non-Issues ... I add between 8 and 10 pounds for the 5 or 7 based on what I use for a 3mil. Both have been in that 300' range many times....the water temps here are in the 80's to upper 80's all year long (it's not that much colder, even very deep, I've welcomed the cooler depths often, it was so warm above). As long as you're comfortably warm at depths where the suit is compressed,... Wetsuit compresion as an issue on deep dives is a load of dung that some folks shovel to push dry suits, there's no other logical rationale. Exposure protection is there to keep you warm, if what you have does that, that's all that you need. You wear a BC to take care of the bouyancy issues.
Darlene
Darlene
Dryglove
Contributor
That answered my question. If your wetsuit is fully compressed at 60ft its gonna have the same buoyancy characteristics at 150ft.
People make it sound like the deeper you go the more buoyancy your gonna lose due to your wetsuit compressing. But if your wetsuit is fully compressed at 60ft theres not much to lose. The main thing as you have stated is that you are warm and have a bc with enough lift to offset the wetsuit compression and being properly weighted.
Don Burke
Contributor
The answer you got was "not much of an issue" not "fully compressed".
I have a heck of a time figuring out what is compression of my wetsuit and what is compression of the bubble in my BC when it comes to buoyancy.
I also have a heck of a time figuring out what is compression of my wetsuit and what is thermocline when it comes to thermal performance.
Below about 40-50, put me in the "not much of an issue" category. Then again, my current wetsuit is getting pretty old.
That was one of the themes of the article. The author greatly overstated the problem and then expanded on that.
I endorse the statement, "The whole story is an excercise in sensationalism, speculation, and scare tactic."
If the wetsuit was fully compressed, there would be nothing to lose.
In practical terms, the difference between a wetsuit at about 50 feet and the same wetsuit at 200 feet gets lost in lung volume and changes in water density due to temperature. It doesn't fully compress.
The same pressure that takes the buoyancy also reduces the R-value. It has to be pretty warm to be doing deep wetsuit dives of any length. The people who dove the Andrea Doria wet were nuts IMO.
One of the things that was brought up was the concept of doing a screaming descent to get more bottom time. The difference between 60fpm and 120fpm doesn't come to very much bottom time. It's false economy.
The big BC was to be used as a dive brake or lift bag. I think those are also bad ideas. There are better ways to accomplish both things.
Scuba_Vixen
Guest
I can relate some of the things that irritate me so much when I see those piles of horse feathers, that seem so easy for the average diver to believe. I live on an island in the caribbean, we have a dive location that is touted as the closest to shore true wall of anywhere in the world. It's a couple hundred yards out from a nice beach with a diveshop and beachbar and grill. (several of them in a row, actually) The top of the wall is a deep spur and groove formation, big coral heads with sand chutes between like canyons.They slopedown from about 50' to 80' depth. At the 80 to 90' point, you're looking down the steep slope of the wall. It looks like it goes endlessly down into the blue. Your natural assumtion is that it's a steep sand and plant life slope all the way to God knows where. The depth between here and the next island north (about 40 miles away) is 13,000' plus. It's truely some wonderfull diving. The water temp runs about 85F and vis is 80 to 100' average, sometimes close to 200'. It doesn't take any great level of advanced training to dive the wall, if you pay attention to your gages and set realistic depth limits based on skill and experience, you'll be fine. There are Very few mishaps, and most tend to be minor. While you might expect divers to get bent a lot because of the depths available, it doesn't happen.
Unfortunately.... It seems every few years, we loose a diver (or 2) to stupidity...alcohol and/or testosterone are usually involved somewhere.
And they never had to try to get a DO to take them out there, or charter a small boat from college kids, and they never hatched the hokey idea to try to go down like a crate of cannon balls..... Now tell the truth, how many of you that read the story said to yourselves, "what morons, I'd never do anything that stupid!" ....
My point Exactly, you all did. That's what made the story not apply to you, and feeling safe from the same mistakes they made, you read on out of amusement, actually loosing the real warnings of risk of diving too deep. (relative to skills, training, equipment, and conditions)
Divers get into trouble for two reasons:
#1 is they Overestimate their ability, and
#2 is they Underestimate the requirements of the dive
Either way, what you don't know can kill ya.
Now getting back to the real life eqivalents to the guys in the story.... As you go out over the wall, when vis is quite good, you look down and it looks like an open elevator shaft way down below. It looks about 10 yards diameter, and "not that much deeper to get there or take a closer look" It's like a syren of the deep calling suseptable divers. Actually, at 220' on air, it looks like you're almost there, maybe 50' more to go. Our guys aren't about to die yet, so they ascend and after a few beers and burgers on the surface interval, decide to dive the hole. Neither has had nitrox training where they would have learned about O2 toxicity at depth ... all that PO2 stuff and CNS hits and such. Both are young and strong and are used to the buzz off a 6 pack, woooaaaa, who can't handle a 6 pack and still drive....I bet every one of you know one of these guys, some see him in the mirror in the morning. But off they go, down the beach into the water for their last dive, not that they have that thought yet though. But, hey, when you're not gonna get narc'd, or if ya do, you can handle it easy, then what's to go wrong!
Well, you can see where these guys are gonna end up, either narc'd into semiconsciousness and airing up a bc and doing the polaris missle ascent, or drowning after the cns hit and never being recovered.
The really bothersome thing about the guys we loose here, is that they are about like most of the rest of the newer, less skilled/experienced, but eager beaver guys we see diving all around us. Trying to scare people into changing their behavior seldom works, (at least in a slasting manner) in example, I give you the gory movies from drivers ed or defensive driving class.
What saddens me most, I think, is that there are still a lot of guys flirting with diving the hole, I get them every so often as I gear up or I'm rinsing off after at the shop there, tell me how deep they went, or what it's like inside, or to see it close up. I smile, shrug, and suggest more training and proper gear. If I tell them what's really there, they'll know I know they lied/exaggerated grossly...and then they'll really try to go there and see if I'm putting them on.
Anyway, thanks for letting me ramble on, Just don't call me Sea Jay, his rambles are wayyy better than mine. But if I make someone rethink a foolish dive, I've accomplished something positive. I doubt anyone rethought anything from that tabloid scare tale. Maybe next ramble I'll tell ya what's really down there, it's wayyy more awesome.
Darlene
Unfortunately.... It seems every few years, we loose a diver (or 2) to stupidity...alcohol and/or testosterone are usually involved somewhere.
And they never had to try to get a DO to take them out there, or charter a small boat from college kids, and they never hatched the hokey idea to try to go down like a crate of cannon balls..... Now tell the truth, how many of you that read the story said to yourselves, "what morons, I'd never do anything that stupid!" ....
My point Exactly, you all did. That's what made the story not apply to you, and feeling safe from the same mistakes they made, you read on out of amusement, actually loosing the real warnings of risk of diving too deep. (relative to skills, training, equipment, and conditions)
Divers get into trouble for two reasons:
#1 is they Overestimate their ability, and
#2 is they Underestimate the requirements of the dive
Either way, what you don't know can kill ya.
Now getting back to the real life eqivalents to the guys in the story.... As you go out over the wall, when vis is quite good, you look down and it looks like an open elevator shaft way down below. It looks about 10 yards diameter, and "not that much deeper to get there or take a closer look" It's like a syren of the deep calling suseptable divers. Actually, at 220' on air, it looks like you're almost there, maybe 50' more to go. Our guys aren't about to die yet, so they ascend and after a few beers and burgers on the surface interval, decide to dive the hole. Neither has had nitrox training where they would have learned about O2 toxicity at depth ... all that PO2 stuff and CNS hits and such. Both are young and strong and are used to the buzz off a 6 pack, woooaaaa, who can't handle a 6 pack and still drive....I bet every one of you know one of these guys, some see him in the mirror in the morning. But off they go, down the beach into the water for their last dive, not that they have that thought yet though. But, hey, when you're not gonna get narc'd, or if ya do, you can handle it easy, then what's to go wrong!
Well, you can see where these guys are gonna end up, either narc'd into semiconsciousness and airing up a bc and doing the polaris missle ascent, or drowning after the cns hit and never being recovered.
The really bothersome thing about the guys we loose here, is that they are about like most of the rest of the newer, less skilled/experienced, but eager beaver guys we see diving all around us. Trying to scare people into changing their behavior seldom works, (at least in a slasting manner) in example, I give you the gory movies from drivers ed or defensive driving class.
What saddens me most, I think, is that there are still a lot of guys flirting with diving the hole, I get them every so often as I gear up or I'm rinsing off after at the shop there, tell me how deep they went, or what it's like inside, or to see it close up. I smile, shrug, and suggest more training and proper gear. If I tell them what's really there, they'll know I know they lied/exaggerated grossly...and then they'll really try to go there and see if I'm putting them on.
Anyway, thanks for letting me ramble on, Just don't call me Sea Jay, his rambles are wayyy better than mine. But if I make someone rethink a foolish dive, I've accomplished something positive. I doubt anyone rethought anything from that tabloid scare tale. Maybe next ramble I'll tell ya what's really down there, it's wayyy more awesome.
Darlene
lal7176 once bubbled...
At what depth would a wetsuit compress to its max and no longer be affected by the pressure as it is compressed to its max. Lets just use a 7mm as an example.
The reason i am asking if a wetsuit is fully compressed at lets say 90ft what difference would it make if you used at 150ft if it is already fully compressed at 90ft. It shouldnt affect your buoyancy a whole lot more.
I dive a trilam drysuit so i dont have to deal with all the wetsuit isues with losing buoyancy.
At what pressure is Nitrogen "Fully compressed"? The gas in the suit is responsible for the compression.
Yhea, I was wondering about that quote too. Little did I realize that being a couple thousand feet back in a cave wasn't technical because I was wearing a wetsuit..
Roak
Scuba_Vixen
Guest
"At what pressure is Nitrogen "Fully compressed"? The gas in the suit is responsible for the compression."
Really comes thru when you figure the suit is compressed to a point where there's maybe a pound or so more bouyancy that could be squeezed out of it at near infinite depth by the time you get to about 60 feet or so. For all Reasonable intents and purposes, That's Fully Compressed. If you are properly weighted, and have a properly sized wing...and you can stay neutral at 60', then you can be neutral at 160', or 260'. Argueing over that small a bouyancy change is no more intelligent than saying a nitrox blend has to be accurate to less than one tenth of one percent.
DeepTechScuba once bubbled...
Wetsuits are definitely NOT technical gear. Diving deep with a wetsuit on is russian roulette, if not suicide.
How about giving us some supporting facts and a connected series of statements to validate that conclusion........ Or did you just swallow the whole shovel load.......
I wouldn't suggest wetsuits for most deep or technical diving, but they do have there niche.
Darlene
Really comes thru when you figure the suit is compressed to a point where there's maybe a pound or so more bouyancy that could be squeezed out of it at near infinite depth by the time you get to about 60 feet or so. For all Reasonable intents and purposes, That's Fully Compressed. If you are properly weighted, and have a properly sized wing...and you can stay neutral at 60', then you can be neutral at 160', or 260'. Argueing over that small a bouyancy change is no more intelligent than saying a nitrox blend has to be accurate to less than one tenth of one percent.
DeepTechScuba once bubbled...
Wetsuits are definitely NOT technical gear. Diving deep with a wetsuit on is russian roulette, if not suicide.
How about giving us some supporting facts and a connected series of statements to validate that conclusion........ Or did you just swallow the whole shovel load.......
I wouldn't suggest wetsuits for most deep or technical diving, but they do have there niche.
Darlene
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