Cave 1 course

[Slym]

I put my deposit down for my intro to tech, cavern, and cave 1 course in Febuary and have been reading the books religiously. Few statements in the book are made that don't seem to have a follow up. For sure I am going to bring it up with the instructor but it's always nice to have a few perspectives.

The book mentions that you need a second source of gas for a drysuit when you are breathing a helium mix, doesn't say why. Is this a cost thing because it's expensive, or does it have to do with how light the helium is? As I know you can use argon as well.

The second thing mentioned is a 0 viz exit by team contact. I just can't visualize it, how would you hold your team mate infront of you on an exit if you need to kick, the only thing to touch is the other persons legs.

I know come my course this will be cleared up but I am loving the new learning and understanding this material I've been given.

 

[WetRocks]

In addition to the expense, the main reason you don't want to use He for drysuit inflation is to stay warm. The thermal conductivity of He is about 5x that of air. Some people swear by Argon but the gist is you want to use anything but He. We usually just use air in a suit inflation bottle.

Regarding the zero-viz exit, the key is in proper non-silting propulsion technique In a modified frog kick, your propulsion is from the lower leg and ankles, not the hips. So the knees stay relatively still. Think about proper diver position... your body is flat / horizontal from head to knee, lower leg is up. So Diver 2 holds Diver 1's knee in one hand and the line in the other. Head down so as not to get kicked. Easier to visualize with a stick figure drawing perhaps...

 

[mafi]

You cannot use helium because it’s really good heat conductor, which is exactly what you do NOT want. You need something that will not conduct the heat away from you - air, or better yet, argon.

As for the touch contact exit, there are protocol on how to do that which you will practise during the course both on land and in the water.

I recommed watching this awesome video about cave course:

 

[rjack321]

how would you hold your team mate infront of you on an exit if you need to kick, the only thing to touch is the other persons legs.

I know come my course this will be cleared up but I am loving the new learning and understanding this material I've been given.

1) You're legs aren't flutter kicking so parts of your legs are comparatively stable - even if the need to hold onto your buddies thigh is limited/non-existent 2) There are plenty of other things (like an upper arm/elbow) that are fine for touch contact in Cave1. Cave2/full cave restrictions presents some additional challenges but they aren't that perplexing because (in part) in a restriction there's not really any other place for anyone to go.

Its part of the course, just go with an open mind and good buoyancy. The other posters covered suitgas,

 

[decompression]

How many weeks are you spending training in February?

 

[Slym]

How many weeks are you spending training in February?

I believe intro to tech is a few days, cave 1 is about a week. Likely will take 3 weeks off to just cave dive in Lauraville (ginnie/peacock) My diveshop rents a place in the area for a few weeks and it is like a divecamp for tech divers, super cool.

 

[decompression]

I believe intro to tech is a few days, cave 1 is about a week. Likely will take 3 weeks off to just cave dive in Lauraville (ginnie/peacock) My diveshop rents a place in the area for a few weeks and it is like a divecamp for tech divers, super cool.

Nice, enjoy, take it slow, learn as much as you can. You are cramming a lot of training into a relatively short amount of time, allow it to process and dive safe!

 

[Slym]

Nice, enjoy, take it slow, learn as much as you can. You are cramming a lot of training into a relatively short amount of time, allow it to process and dive safe!

Thanks! I am hoping to be ready for the course, my biggest concern will be changing drysuit types and getting use to bp/w and 1/2 mask again. Taking it with a familiar buddy though, so that helps.

 

[rddvet]

Not to discourage but that's a lot of class at one time. Sounds like you're doing the naui system based off the classes. I did Intro to tech/ cavern together. I then sharpened my skills and dove doubles a lot then months later moved to cave 1. Strayed there for a year or so then moved to cave 2.
Do you have experience in doubles? Have you discussed that many courses all together with your instructor and the alternative of pushing cave 1 off a while? If you've had lots of doubles time and already did intro to tech I'd say cavern/intro would be no issue. If you're new to tech diving, then I personally would take it slower.

Not trying to discourage you, but that's a lot to take in with no tech experience.

 

[Topper133]

The book mentions that you need a second source of gas for a drysuit when you are breathing a helium mix, doesn't say why. Is this a cost thing because it's expensive, or does it have to do with how light the helium is?

There is the thermal conduction as discussed, there is the cost of He, and there is also Isobaric Counter Diffusion, subcutaneous ICD, where an exposure suit filled with light gas, but you're breathing heavy gas, and the differential can actually enable gas transport, which can increase the likelihood of DCS.

**Caveat, I am no expert on this subject matter**.