Decompression Sickness

Decompression sickness is a condition resulting from inadequate release of
excess nitrogen absorbed during a dive. Decompression sickness is not the
same as decompression illness. Decompression illness is a term which
describes both overexpansion injuries, including arterial gas embolism
(AGE), and decompression sickness (DCS) for purposes of treatment. (SSI
Open Water Diver Manual, Third Edition, December 1995.)

Technical Diving International (TDI) defines decompression sickness as a
series of maladies associated with nitrogen or other gas coming out of
solution of the blood or tissues, sometimes as bubbles. This may cause just
simple pain or be associated with severe neurological effects. (©J. Odom
and International Training 2000 Rev 1b.) The TDI definition is more
expansive to encompass other gasses that may be used in technical diving.

What is risk? Risk is a concept related to human expectations. It denotes
a potential negative impact, in the case of SCUBA, to your health that may
arise from gas coming out of solution too quickly. Scuba involves inhaling
compressed air. The act of breathing compressed air under water leads to
gas coming out of solution once the pressure of the water is reduced or
eliminated. The risk of DCS or decompression illness exists until your body
has again gained gas equilibrium in air.

Decompression symptoms usually occur within 8 hours but can occur even after
24 hours. Decompression symptoms rarely occur during a dive. There are
many diving factors or conditions that contribute to DCS including, just to
name a few, ascent rate too rapid, heavy work load, cold, and dehydration.
There are post dive activities that contribute to DCS including flying and
strenuous exercise, just to name two.

What can you do to minimize the risk associated with decompression illness?
For starters, follow your scuba training, hydrate before and after diving,
control your ascent, monitor your limits, decrease your work load, keep
warm, don't fly for 24 hours after your last dive, and avoid strenuous
exercise. You can in fact reduce the risk of DCS. Every scuba course
you've ever taken, more than likely, has been about doing just that.

ben bradlee wrote:

> Decompression sickness is a condition resulting from inadequate release of
> excess nitrogen absorbed during a dive. Decompression sickness is not the
> same as decompression illness. Decompression illness is a term which
> describes both overexpansion injuries, including arterial gas embolism
> (AGE), and decompression sickness (DCS) for purposes of treatment. (SSI
> Open Water Diver Manual, Third Edition, December 1995.)
>
> Technical Diving International (TDI) defines decompression sickness as a
> series of maladies associated with nitrogen or other gas coming out of
> solution of the blood or tissues, sometimes as bubbles. This may cause just
> simple pain or be associated with severe neurological effects. (©J. Odom
> and International Training 2000 Rev 1b.) The TDI definition is more
> expansive to encompass other gasses that may be used in technical diving.
>
> What is risk? Risk is a concept related to human expectations. It denotes
> a potential negative impact, in the case of SCUBA, to your health that may
> arise from gas coming out of solution too quickly. Scuba involves inhaling
> compressed air. The act of breathing compressed air under water leads to
> gas coming out of solution once the pressure of the water is reduced or
> eliminated. The risk of DCS or decompression illness exists until your body
> has again gained gas equilibrium in air.
>
> Decompression symptoms usually occur within 8 hours but can occur even after
> 24 hours. Decompression symptoms rarely occur during a dive. There are
> many diving factors or conditions that contribute to DCS including, just to
> name a few, ascent rate too rapid, heavy work load, cold, and dehydration.
> There are post dive activities that contribute to DCS including flying and
> strenuous exercise, just to name two.
>
> What can you do to minimize the risk associated with decompression illness?
> For starters, follow your scuba training, hydrate before and after diving,
> control your ascent, monitor your limits, decrease your work load, keep
> warm, don't fly for 24 hours after your last dive, and avoid strenuous
> exercise. You can in fact reduce the risk of DCS. Every scuba course
> you've ever taken, more than likely, has been about doing just that.
>
>
>
Other than staying out of the water, you CAN NOT reduce yer DCS
risk below about 0.0004, depending who's doing the stats and
what they consider a valid hit.

If you "follow your scuba training, hydrate before and after
diving, control your ascent, monitor your limits, decrease your
work load, keep warm, don't fly for 24 hours after your last
dive, and avoid strenuous exercise" yer risk is about 0.0004.
Nothing you do can reduce that risk. Nothing.

Greg Mossman wrote:
> "mike gray" <omgray@worldnet.att.net> wrote in message
> news:jkpBg.220931$mF2.87762@bgtnsc04-news.ops.worldnet.att.net...
>
>
>>If you "follow your scuba training, hydrate before and after diving,
>>control your ascent, monitor your limits, decrease your work load, keep
>>warm, don't fly for 24 hours after your last dive, and avoid strenuous
>>exercise" yer risk is about 0.0004. Nothing you do can reduce that risk.
>>Nothing.
>
>
> Would you agree that if you're not as well-hydrated as you should be from
> all the drinking the night before, if you do a faster ascent than you should
> because you're in a hurry, do moderate work underwater (prying scallops,
> say), in cold water on a cold night, and have to strenuously hike your gear
> up a steep hill after the dive, that your risk might be greater than 0.0004?

Not within modern recreational tables, no.
>
> If so, wouldn't using nitrox on air tables tend to counterbalance the
> increased risk from the other factors?

Using nitrox on air tables could very well increase yer risk.
>
> If not, then why worry about any "risk" factors?

I'm a geriatric insulin dependent diabetic in rather poor shape.

I stay within the tables for the gas I'm diving and don't worry
about anything.

On Mon, 07 Aug 2006 01:33:29 GMT, mike gray <omgray@worldnet.att.net>
wrote:

>Using nitrox on air tables could very well increase yer risk.

How?