What line do you prefer follow?

[Jax]

Not a cave-diver here . . . what is the story behind telephone cable?

[Greenwood_60]

I think someone mentioned earlier that it was run through sumps in caves that were primarily dry, to facilitate communication between the two sides. I took it as a joke regarding internet divers.

[CaveBuddy95]

Absolutely right Greenwood, it was used and probably could still be installed, as a mean of communication in sump exploration. Not necessarily from the entrance but could be from an advance base camp to the furthest remote access of the cave.

We know that internet divers use broadband nowadays!

[NEON]

I didn't say 'you' were complacent.
And I still believe having too much of a set of physical references (line and markers) and being taught to use them to find your way out is not the right way to do it.

Take example of a survey dive, the first time the diver goes in, he/she will survey the line. But to produce a map that is going to be of any use for divers and others, the survey team need to survey the cave.
The line is just a path in the cave and is here to help in zero viz exit...if any!

Having a very visible and thick line could create complacency by creating a false idea that what ever happens, this same line will take me out. I think.

What would be "the right way" to teach in your opinion?

[AMW]

I normally us 4mm polypropylene in and out tagged every 5M:






From 1980,s


Although as long as it floats I do not mind.


Line laying practise (Some may have already seen it). music I like and has no relevance to the video

Andrew

[CaveBuddy95]

What would be "the right way" to teach in your opinion?

Hey there, if you ask me I'd say cave referencing, as much as line referencing. Too many times divers are thought just to follow the line and trust their life to a plastic marker or a nylon line ( a bit about this later) and I don't think it's a good idea. IANTD standards state a skill (#20) in which the student is to exit without light and without the line... apart from doing a 'lost line drill' I don't see the point. What could be interesting is to 'try' to exit without the line but with light. There, cave referencing would probably save your life.

I normally us 4mm polypropylene in and out tagged every 5M:

Although as long as it floats I do not mind.

Andrew

floaty line is not a good idea, unless in sea caves where polypro is more resistant and has to be a very thick line. In Mexico the tie offs are often done in stalagmites and a thin line is less damaging that a very thick one. On the other hand, entanglements hazard with floaty lines are real, so it is down to the type of diving you do for sure.

[AMW]

floaty line is not a good idea

As you say it depends on the diving you do, diving in low vis silty caves the last thing you want is a line on the floor that becomes between dives covered in silt that is displaced as you move along it. You should never be proscriptive as to what is good or bad as nothing suits all conditions. For your diving non floating lines may work in other areas it may not be the best choice (horses for courses).

Andrew

[DA Aquamaster]

As you say it depends on the diving you do, diving in low vis silty caves the last thing you want is a line on the floor that becomes between dives covered in silt that is displaced as you move along it. You should never be proscriptive as to what is good or bad as nothing suits all conditions. For your diving non floating lines may work in other areas it may not be the best choice (horses for courses).

Andrew

different strokes for different folks I guess. I've been in small silty tunnels with old, loose or broken line down in the silt. Personally, I'd rather have nylon line there than a floaty poly-pro line. The nylon line may become uncovered, but it will stay there. Poly pro line that was pulled down and covered in a flood event would refloat when freed of silt and that could be loads of fun exiting in low viz in tight passage.

On the other hand if it stayed floating and was just loose going in, it could be replaced in hopes of it being snug on the way out. However if it again comes loose before I exit, I want it on the bottom, not potentially trying to float above/behind me in a low viz exit.

[Jax]

Thanks for the history lesson on the phone cable.

[FW]

Being both US (NSS-CDS) and UK (CDG) trained, I have to point out that the UK sump divers have a lot more experience in low visibility cave diving.

If you want to read an interesting IRAP which points out the problem with Nylon line buried in the silt, read this: http://www.cavediver.net/forum/showt...5518-Lost-line