David Strike wrote:

> I didn't start a thread on swim-throughs.

Whether you intended to or not, you did.  My post didn't mention swim
throughs, it addressed caves.  Yours specifically addressed swim throughs.

> To suggest that 'unqualified' people shouldn't enter a swim-through would
be
> patently absurd . . .

Then you have my permission to call me patently absurd.  I was quite careful
to use the term qualified as opposed to certified.  The terms are not the
same.  I think it is perfectly reasonable to say that someone whose
experience is limited to 4 qualification dives, who can't even remember to
check his on gas supply until it's too late (pretty much the situation in
the article) should not be in an overhead environment, any overhead
environment.  Every entry level certification agency I know of agrees,
including the one or ones under whose rules you have taught.

It's a bit harder for someone to judge when another diver's experience is
sufficient for that person to conclude he or she is qualified for an
overhead environment.  Fortunately, it's not my job to decide when someone
is qualified.  I asked only that those who are not, stay out of caves and,
since this topic is about swimthroughs, out of any of them they are not
qualified to enter as well.  In my opinion, my statement is a direct
application of the theory of knowing your limits and diving within them to
diving in overhead environments, nothing more, nothing less.

> The real questions that I was posing were, "When does a swim-through
become
> a cave?  Or should all and any overhead environment situation require some
> sort of qualification?"  :-)

You've asked two questions.  The first may be a bit easier than the second.
I've never seen a specific definition of a swim through.  I define the term
as a passage which is entered at one end and exited at another, non
technical but useable for me.  According to definitions by some certifying
agencies, all swim throughs are at least caverns by virtue of the hard
overhead.  They become caves, by the definition of these same agencies when
you are deeper, further in horizontally and/or out of direct line of sight
to natural light than standards they set.  I'm not real fond of that
definition.  I prefer a simpler defintion.  If I can't navigate by natural
light, I'm in a cave.  It's interesting to note that it seems that a cavern
could turn into a cave without changing position, simply with a kick that
stirs up silt.

The second question addresses the need for some sort of qualification.  I
don't think there's a hard answer for this.  I do, however, thing the need
for increased qualification exists before a swimthrough/cavern becomes a
cave.  Your use of the term qualification makes this particularly hard for
me to address.  It does not appear we're using the term the same way.  As I
see it, qualification implies skills, knowledge and ability.  It does not,
to my knowledge, require a certificate attesting that one has met the
standards of an agency in the business of issuing C-cards.  I believe one
can be qualifed without having the card and unqulalified despite having one.

Using this definition, my opinion is that any swim through that increases
risk should be attempted only by a diver who is qualified to handle the risk
and that any overhead environment increases risk.  It is quite possible that
the shortest of swimthroughs, such as a natural arch, increase risk by such
a small amount that anyone qualified to do the dive otherwise probably has
the qualifications for the narrow overhead.  The longer, deeper and narrower
the swimthrough, the more qualifications are needed to do it safely.  If you
mean "certified" rather than my "qualified," then I don't have an answer.
I'll leave it to those to offer certification to define what they are
certifying for.  I don't represent them and they don't represent me.

Lee