Going down fast. Dive thread!

On Fri, 23 Feb 2007 13:15:35 -0500, "Lee Bell"
<pleebell2@bellsouth.net> wrote:

>> I missed the point in this discussion where we were or were not in
>> favor of the ok sign upon entry to the water. Also, I seem to remember
>> reading somewhere that you should control your decend as you do your
>> ascend. Any thoughts ?
>
>The OK sign upon entry is a courtesy to the operator of the boat,
>particularly when the boat is not moored, drift diving, for example.
>Whether or not you extend that courtesy is pretty much up to you. I
>generally don't and, except when I think I've run into a real anal operator,
>normally tell them not to expect one. If they insist, they're likely to get
>a very different sign as I enter the water.
>
>Lee
>
>
I seem to remember a discussion on here about "long bone embolisim
(sp) " on rapid descent a few years ago

"Lee Bell" wrote

>>> I think that it is perfectly ok to descend as quickly as you can. If
>>> you are properly weighted you won't be going that fast anyhow.
>
>> Not necessarily. I will be able to drop like an anchor on Sunday, and
>> I'll be weighted only about 2 lbs heavy. (OK, so I'm diving doubles /
>> stage, 255 CF of gas start).
>
> Naughty, naughty, fooling your fellow rec.scubans. When you start your
> drop, you'll be a darned sight more negative than 2 lbs.

OK, so I intend to ditch a lot of weight during the dive by breathing.


>> I'll let y'all know how Key Largo is, if somebody, like my dive buddy,
>> doesn't beat me to it.
>
> Dive buddy? You mean someone is actually willing to dive with you? Doing
> a shallow reef with Captain PADI, are you?

He did make an offer I think to allow you to do one three hour dive on
our favorite shallow reef site.

Curtis

On Feb 24, 7:01 am, log_...@verizonnet.addthedot (Rod) wrote:

> I seem to remember a discussion on here about "long bone embolisim
> (sp) " on rapid descent a few years ago

Ouch. I can't think of any fate worse than embolizing the long bone.

It's a fact that rapid descents can lead to HPNS on those really deep
dives. The guidelines stress not descending any faster than 1 fsw/
minute when using trimix below 600'. I know I don't.

"At diving depths greater than 600 fsw (183 msw), signs and symptoms
of a condition known as the high pressure nervous syndrome (HPNS)
appear and become worse the faster the rate of compression used and
the greater the depth or pressure attained. HPNS is characterized in
humans by dizziness, nausea, vomiting, postural and intention tremors,
fatigue and somnolence, myoclonic jerking, stomach cramps, decrements
in intellectual and psychomotor performance, poor sleep with
nightmares, and increased slow wave and decreased fast wave activity
of the brain as measured by an electroencephalogram (Bennett et al.
1986)."

Therefore, if you have myoclonic jerking of your long bone, I suggest
descending slower.

On Sat, 24 Feb 2007 08:16:56 -0500, "Lee Bell"
<pleebell2@bellsouth.net> wrote:
> We noticed you felt that way when we did the Spiegel.

Yeah, I guessed wrong on how much lead I was going to need with those
tanks in salt water and not diving my full FJ 5mm wetsuit... One of
the problems of not always diving the same gear configuration... If I
ever end up with a contract down in Florida, I'll have a chance to
determine exactly how much lead I need in all gear configurations...
So far, none have come up down there... Instead, I get choice dive
locales like IOWA !!!

Magilla wrote

>> Naughty, naughty, fooling your fellow rec.scubans. When you start your
>> drop, you'll be a darned sight more negative than 2 lbs.
>
> OK, so I intend to ditch a lot of weight during the dive by breathing.
>

10-4 good buddy

> He did make an offer I think to allow you to do one three hour dive on our
> favorite shallow reef site.

Oh goody goody. Actually, if I could get down there quickly enough, I'd
probably take him up on it this afternoon. It doesn't look like I'll make
it. I still haven't sorted out everything to load the car, let alone
actually put it in the car. I may run up to Fill Express to see if they'll
bump the pressure in my tanks just a bit. They're dead on Speaking of
loading the car, I'll be bringing an inexpensive, but adequate, hand truck
to move stuff from car to boat. You're welcome to use it if it won't
embarass you too much.

Jayna got me a room at Amy Slate's Amore Divers for tonight. I got the last
room and, unfortunately, it only has one bed. It may, however, have a
couch. I've not seen it, so can't be sure one way or the other. I'll let
you know as soon as I know. See you at the motel, see you at the shop, or
see you on the boat.

By the way, a quick calculation at my normal SAC indicates it would take
more than 4 hours for me to test my weighting with the twinset. Then again,
I could always hold the purge valve open on the alternate while I breath off
the primary. Hmmm, I wonder if it's possible to freeze a first or second
stage in sub tropical water.

Lee

Greg Mossman wrote:
> On Feb 24, 7:01 am, log_...@verizonnet.addthedot (Rod) wrote:
>
>
>>I seem to remember a discussion on here about "long bone embolisim
>>(sp) " on rapid descent a few years ago
>
>
> Ouch. I can't think of any fate worse than embolizing the long bone.
>
> It's a fact that rapid descents can lead to HPNS on those really deep
> dives. The guidelines stress not descending any faster than 1 fsw/
> minute when using trimix below 600'. I know I don't.

I don't either.

HPNS is even more poorly understood than N narc and oxtox, but lacks
their wild and sexy myths.

Let's start some.

I once got an HPNS hit at 20 fsw after eating too much lobster the night
before and not getting enough sex to work it off. Definitely a long bone
problem.

esg

"El Stroko Guapo" <omgray@earthlink.net> wrote in message
news:2c%Dh.6070$tD2.4401@newsread1.news.pas.earthl ink.net...

"I once got an HPNS hit at 20 fsw after eating too much lobster the night
before and not getting enough sex to work it off. Definitely a long bone
problem."

There's my next diving t-shirt.

El Stroko Guapo wrote:
> Greg Mossman wrote:
>
>> On Feb 24, 7:01 am, log_...@verizonnet.addthedot (Rod) wrote:

>>> I seem to remember a discussion on here about "long bone embolisim
>>> (sp) " on rapid descent a few years ago

>> Ouch. I can't think of any fate worse than embolizing the long bone.
>>
>> It's a fact that rapid descents can lead to HPNS on those really deep
>> dives. The guidelines stress not descending any faster than 1 fsw/
>> minute when using trimix below 600'. I know I don't.

> I don't either.
>
> HPNS is even more poorly understood than N narc and oxtox, but lacks
> their wild and sexy myths.
>
> Let's start some.
>
> I once got an HPNS hit at 20 fsw after eating too much lobster the night
> before and not getting enough sex to work it off. Definitely a long bone
> problem.
>
> esg

This is why I love rec.scuba!

On Feb 24, 9:10 am, Grumman-581 <grumman...@DIE-SPAMMER-SCUM-
gmail.com> wrote:

> Yeah, I guessed wrong on how much lead I was going to need with those
> tanks in salt water and not diving my full FJ 5mm wetsuit... One of
> the problems of not always diving the same gear configuration... If I
> ever end up with a contract down in Florida, I'll have a chance to
> determine exactly how much lead I need in all gear configurations...

Funny, you'd think an engineer could read the various charts comparing
weight parameters of various tanks and figure out the differences.
Heck, I'm a lawyer and I figger it just fine.

On 24 Feb 2007 23:57:58 -0800, "Greg Mossman" <mossman@qnet.com>
wrote:
> Funny, you'd think an engineer could read the various charts comparing
> weight parameters of various tanks and figure out the differences.
> Heck, I'm a lawyer and I figger it just fine.

Here's the factors:
1. Steel tanks vs aluminum tanks
2. Full FJ 5mm wetsuit vs FJ top vs FJ bottom vs no wetsuit
3. Salt vs fresh water

Thus 2 * 4 * 2 = 16 different weighting possibilities... I believe I
was just using the FJ top on that dive, but I carried enough lead for
the full FJ wetsuit... Oh well, it's better than not having enough
lead and constantly be fighting to get down...