cavern/cave diving on Oahu

[murfef]

We tried to get a last dive in at Sharks this morning but decided against it, we had some really new divers with us. Oh well. We went over to E-Beach instead. It was ok, it was my first time there so I enjoyed it. I'm not sure if there is more to see or not. Just went out around the pipes which had lots of pretty fish but after a few minutes there, I was ready to go. Is there anything further out or to the left and right? Where are some other dive locations since it seems the North Shore is done for the year?
As far as running lines, I don't want to mess anything up in a protected area, I don't want to mess up anything in any area for that matter. I just want to get some practice in and I'm not sure how running line in one area would impact anything any worse than another area. I'm just not sure if someone would cut my line. Anyway, doesn't look like I'll be diving at Shark's until next year.
I just got a set of doubles that I'm pretty excited about strapping on. Never dove doubles so I bet it could be quite comical. I just need a DIN 1st stage if anyone has one cheap.

 

[MauiScubaSteve]

So murfef, do you have a Cavern trained buddy?

Here in Hawaii, if you stay within your overhead training limits there is very little chance for a silt out requiring a line. Are you just practicing within the true "Cavern" by definition?

You do know the full history behind active duty military and cave diving, especially at Shark's Cove, don't you?

 

[murfef]

No, I don't have a Cavern trained buddy. As far as cavern diving limits, I haven't found anything that even comes close. I'm sure there out there, I just haven't found them, all I've seen so far are swim throughs and a couple of "caverns" that only seem to go back about 20-30ft. That compared to the 200ft from the surface that is allowed by "cavern" definition, it's not very much.

I haven't had a chance to practice at all yet. I haven't found any caverns to dive or a buddy to go in them with and I'm not sure I trust the OW divers to not cut my line. Besides all of that, I spent the weekend diving with my wife which was good, it was her first actual dives after getting OW cert.

What does "very little chance" mean? Does it mean I could bet my "LIFE" on it? It would have to be a dead end tube with absolutley no shoot offs and no "little holes" to get stuck in. The whole idea of the guide line is for when the "very little chance" actually happens. It's not for when the vis is all great. With my cert, the only limits I have are 1. stay within the daylight zone and 2. no more than 200ft total from the surface. With those two limiting factors, I can still make turns, etc. which could lead to not having a "straight" path out. Maybe the caverns here are nothing like what I'm used to and I may find out later that there really is no need for a line because there is no way to get lost. But as far as practicing, I plan on doing Intro to Cave when I go back to FL. So I'm gonna stay up on any skills that I can. I'm also about to start diving doubles for that same reason.
No, I don't know the history behind active duty military and cave training. Please fill me in. I'm always interested in history, especially military and caving. Great combo!! LOL

 

[MauiScubaSteve]

What does "very little chance" mean? Does it mean I could bet my "LIFE" on it? It would have to be a dead end tube with absolutley no shoot offs and no "little holes" to get stuck in. The whole idea of the guide line is for when the "very little chance" actually happens. It's not for when the vis is all great. With my cert, the only limits I have are 1. stay within the daylight zone and 2. no more than 200ft total from the surface. With those two limiting factors, I can still make turns, etc. which could lead to not having a "straight" path out. Maybe the caverns here are nothing like what I'm used to and I may find out later that there really is no need for a line because there is no way to get lost. But as far as practicing, I plan on doing Intro to Cave when I go back to FL. So I'm gonna stay up on any skills that I can. I'm also about to start diving doubles for that same reason.

With a coral based sand bottom, the sand is very negative and not like silt. If you are within visual of the entrance/exit it would be very, very hard to stir up the vast majority of Hawaii's cavern sand bottoms enough to not be able to see the entrance/exit.

Are you sure those are the only limits to your training level?

What about "restriction" where the buddies can not dive shoulder to shoulder?

What about minimum 40' vis at the start of the dive (ie. no night penetration)?

What about staying in visual sight of the entrance or exit (ie. how do you define "turn")?

I contend that 200' from the surface is "when properly cavern equipped" and for a typical recreational OW rig, typical recreational standards apply (ie. no farther than 130' from surface. Are you using bungied alternate / long hose primary? (my Cavern cert was with "single tank / bungied 7' alternate" and at that time NSS-CDS defined my limit as 130' from surface)

What about "enough gas to get you and a buddy out on one buddies tank from max penetration?"

What about within 80% of NDL limits?

Did you do your Cavern cert in doubles?

 

[murfef]

yes I'm cavern equiped and all I meant by my training restrictions was that being able to see the 'actual exit' isn't one of them. I could be around a corner and as long as I can see light then I'm still in the cavern zone(the daylight zone). After rereading my post I can see how I wasn't clear at all on what I meant. I'm definantly not trying to say that I'm trained to do any complex turns. The other restictions you stated are accurate except that you stated I have to remain in visual sight of the exit/entrance. I just have to remain in the "Daylight Zone"
I take my training and lack of training very serious. I guess that's why when you said "very little chance" it kind of struck a nerve. There are a lot of divers that have died thinking just that. Some full cave trained and some no more than OW. The thing these people usually have in common is that they didn't abide by the 5 rules. They thought they were ok without placing cookies or without running a line or with no training at all.
I did not do my training in doubles. I did it single BM. I intend to learn the doubles so that it's not something else I'm trying to learn during an Intro class. I was taught thirds as far as air and I was taught to ensure there is enough to get me and my buddy out.
Sorry if there was a misunderstanding, I was just refering to the line running aspect of it as that is what we were discussing. I'm sure I'll find what you're saying to be true but until I see for myself, I'll be running a line. I'll probably run one anyway as it only makes me a better diver and that will never be the reason I can't find my way out.

By the way, fill me in on the history. I'm very interested.
safe diving!!

 

[MauiScubaSteve]

No, I don't know the history behind active duty military and cave training. Please fill me in. I'm always interested in history, especially military and caving. Great combo!! LOL

My question was concerning the history of cave diving and active duty military, not cave training and active duty military.

Back in the 70's there were over 100 deaths in the Florida caves and many were NAVY divers. I can not find a link today but AFAIHH, one of the reasons the State of Florida opened up the caves they had closed because of all the deaths was the NAVY making off duty cave diving a court martial offense for NAVY divers.

4 active duty military non-cave certified divers died cave diving at Shark's Cove, in the late '90's I believe.

 

[murfef]

wow, that's interesting. I'll have to try to look that up. I want to find these caves/caverns out at Shark's Cove. I just haven't seen anything like that yet and I guess I may have to wait until next year. If you're ever wanna go, let me know, I'd love to have someone with a lot of experience in the area show me around out there sometime.

 

[MauiScubaSteve]

The "daylight zone" I was trained to is defined as "always within sight of a non-restricted entrance/exit" within 130 linear feet of the surface. Even with a 200 linear foot to surface limit, I do not think the definition of "daylight zone" has changed from "within sight of non-restricted entrance/exit."

http://www.scubaboard.com/forums/ba.../231902-cavern-diving-definitions-agency.html

I'd like to see the varied definitions differentiating cavern from cave diving. I completed Intro to Cave in Spring of '00, and as I understand it, NSS-CDS has changed their definition since I was trained. At that time, NSS-CDS and IANTD were similar enough that I was offered cards from both agencies.

From my NSS-CDS Cavern Diving Manual, cavern diving in standard recreational scuba gear follows these limits;

Direct Sunlight Zone - diver can see the opening (entrance/exit). If you can not see the opening but it is not pitch black, you are in the ambient-light zone. When it is pitch black and you can see nothing without lights you are in the zone of total darkness. Cavern diving is only in the direct-sunlight zone.

130' Maximum Linear Distance from the Surface - Cavern divers must stay within a linear distance of 130' to the surface. Linear distance includes the depth of the entrance plus the distance of penetration. Examples; 30' deep entrance plus 100' penetration, 50' deep entrance plus 80' penetration, 70' deep entrance plus 60' penetration.

70' Max Depth - Below 70' air reserves for dealing with emergencies are too limited and the margin for error becomes too critical.

No Restriction - Buddy teams should be able to comfortably swim side by side. If divers have to swim single file due to localized narrowing that is considered a restriction. Cavern divers are not permitted to pass through restrictions in part because sharing air with standard scuba through a restriction is nearly impossible.

40' Minimum Visibility - The minimum visibility acceptable for cavern diving is 40'.

No Decompression Limits - Cavern divers should stay well within the no-deco limits. When cavern diving, bottom time is the time from leaving the surface until returning from the cavern to a depth of 10' in open water(not ending at start of ascent). Most experienced cavern divers stay within 80% of NDL limits, to allow for any unexpected delays during exit.

Air Supply Limitations - One of the three leading causes of death in underwater caves is failure to reserve adequate air for exiting. This requires at least as much air in each cylinder as both divers (buddy team) used coming in on the two seperate cylinders (basic rule of thirds).

If you are in any of these following situations, you are technically in cave diving territory; ambient-light zone or zone of total darkness, more than 130' linear from surface, deeper than 70', past a restriction less than 2 divers wide, less than 40' visibility, more than 3 minite required saftey stop. Violating the rule of thirds does not put you in cave diving territory, you are just very foolish.

I'd like to hear from more than just North America; CDAA (Australia), CDG (Great Briton), IANTD, TDI, GUE, NACD and any I've missed. Not really interested in what PADI, NAUI and similar mainstream agencies have to say.

http://cavediving.com/what/start/02.htm

Additionally, cavern divers keep the entrance clearly in sight at all times

 

[murfef]

From my NSS-CDS Cavern Diving Manual, cavern diving in standard recreational scuba gear follows these limits;

I get the feeling that you just want to go back and forth on our interpretation of all of this. I'm not trying to argue with you, I thought we were passed what I thought was a misunderstanding but I guess you want to bring it up again. Above is a quote from your last post so does that mean that different rules apply if I'm diving with "cave gear" and not "Recreational gear"?

 

[MauiScubaSteve]

No matter what configuration you dive in, and no matter the agency AFAIK, a Cavern trained diver's training limits include being within direct sight of the entrance/exit; the "direct sunlight zone."