On Thu, 19 Apr 2001 16:27:44 +1000, David Strike <[log in to unmask]> wrote: >On Thursday, April 19, 2001 9:22 AM, Lee Bell wrote: > >(snip) > >> IF YOU'RE NOT QUALIFIED TO BE IN A CAVE STAY THE HELL OUT OF THEM. >You have raised an issue that's been bugging me for some while: That of >swim-throughs! When does a swim-through become a cave? When you CANNOT SEE the light at some CLOSE exit to surface. An excellent topic for thoughts! >In many instances the difference is a difficult to determine nicety! Indeed. Because it is DIVER-dependent. Will elaborate below. >And it's something that few divers give thought to. That's no different from the fact that few divers give sufficient thought to any other form of diving. :-) That's the beauty of being a "self-reliant" diver and practice the rule of "know YOUR limit ...". From that point of view, whether one SHOULD attempt, is experienced enough to attempt, any particular swim-through is NO DIFFERENT from a diver's judgment on doing any OPEN WATER (with no overhead) dive. The ability for one to "head for the surface" in the event of a catastrophic equipment failure is perhaps the "pragmatic" difference between diving a cave and a swim-through, leaving out the silt-out situations in caves not found in any swim-throughs. >For many people - at whatever level of experience - swim-throughs >are an attraction that they're encouraged to experience. Here, I am not sure who encourages whom. In Cozumel, it seems more likely that some "unqualified" divers wants to do the "devil's throat" dive and a dive shop discourages it, than the opposite. It's more of a case that many divers dive BEYOND their own limits, in depth, and in the ability to be self-reliant under certain more challenging environments -- be it depth or swim-throughs, and especially in the swim-throughs in Punta Sur, often indiscriminantly called "devil's throat" in the hundreds of swiss-cheese holes for EASY exit, at any time during a rather lengthy swim-through. >Some of them can be lengthy affairs; others are little more >than a few metres in length. Nevertheless they are still overhead >environments! Aha! So what's such a big deal about an "overhead environment" if the "overhead" part is always escapable within a few kicks to the "open" part? For that matter, the "glass ceiling" (term used for obligated deco) in a dive with "no overhead" is certainly as dangerous, if not more so, than a swim-through where the LIGHT and SURFACE are always within easy reach (for the diver who attempts it). >But even the short ones - particularly when narrow and >obliging folks to swim in single file through them - offer potential >problems if a person in the middle of a small group throws a 'wobbly'! Then the person in the middle shouldn't be there in the first place, if said person can throw a 'wobbly' whatever that is <G> or incapable of being self-reliant and head for the EXIT or get help from the nearest SOB. In that respect, such a swim-through is much safer because a BUDDY or SOB is always CLOSE BY, whereas in open-water with strong current or bad vis that may not be always the case. In ALL cases, the true test is for the individual diver to ANTICIPATE the worst-case scenario and be able to determine how s/he can successfully handle it should it happen. > >Nevertheless, swim-throughs never seem to attract the same concern as do >caves! Why is that? :-) > >Strike Many reasons. Perhaps the simplest one is, in swim-throughs, you can always SEE the light at some CLOSE exit to surface. -- Bob.