"Accidental" Deco

[fdog]

Several weeks ago, we (I work for a fire department) were dispatched to a "rule out medical" emergency.

We arrived to find a SUV by the side of the road. The blonde thirty-something female driver said that her expensive SUV "just died on her" while she was driving down the road talking on her cell phone to her girlfriend. Since she couldn't figure out what was wrong, she called 911.

We stuck out heads inside, and...

• the fuel gauge was on empty
• the annunciator panel said "LOW FUEL"
• the mileage panel said "Miles Until Empty: 0"
• there was a little red light on at the fuel gauge
• and there was a little bing-bong noise going off

We were amazed that despite all these alerts, the driver still was able to [-]go into deco [/-]run out of fuel.


...seriously. We made the comment that this was one of those calls that if we wrote about it in a book, no one would believe it.


All the best, James

 

[DuboisP]

Oh dear, I'm gona die.

i didn't tell that you cannot use it, i told it's not accurate.
even with a Suunto, your decos will be shorter : only 19 min :cool2:

 

[DuboisP]

I'm CMAS** and don't recall being trained to do deco dives. What did I miss?

don't know

http://www.cmas.org/document.php?sessionId=8b03ca89daf67978b9d9f9ef5a47b72e&fileId=894&language=1

II. CMAS TWO STAR DIVER
3 Course content
3.1 Knowledge
Must have a basic understanding of :
Diving physics and physiology, the causes and effects of diving-related illnesses and disorders.
Basic first aid, resuscitation techniques.
The problems associated with diving to greater depths, calculation of air requirements, correct use
of decompression tables.
The selection of dive sites and the principles of dive planning.
The principles and practices of underwater navigation.
3.2 Skills
Be competent in the use of mask, fins, and snorkel.
Be able to swim on the surface wearing full diving equipment but using a snorkel.
Be fully familiar with use of the diving equipment at medium depths.
Be competent in self-rescue and buddy rescue techniques from depths in the lo-30 metre range.
Be familiar with the use of buoyancy adjustment equipment.
Be competent in the use of decompression tables for single and consecutive dives.
Be competent in practise of underwater navigation.

 

[fdog]

i didn't tell that you cannot use it, i told it's not accurate.
even with a Suunto, your decos will be shorter : only 19 min :cool2:

I hope you aren't implying that the shorter schedule is the more correct one.

With the example of 22 minutes @ 120' on air, the USN tables say 6 minutes @ 10', and...ahh...no, I'm not doing that.

In my mind accurate means not feeling tired or lethargic or worried that I pushed it too hard. Everyone has to pick the algorithm that makes them feel that way. If the CMAS tables gives you that, then good for you!

I've tried a lot of tables and algorithms, and VPM +3 makes me feel the best. Including a lot of nitrox dives. Please don't tell me I'm wrong - or VPM isn't acccurate - because my selection doesn't match yours.


All the best, James

 

[DuboisP]

I hope you aren't implying that the shorter schedule is the more correct one.

With the example of 22 minutes @ 120' on air, the USN tables say 6 minutes @ 10', and...ahh...no, I'm not doing that.

In my mind accurate means not feeling tired or lethargic or worried that I pushed it too hard. Everyone has to pick the algorithm that makes them feel that way. If the CMAS tables gives you that, then good for you!

I've tried a lot of tables and algorithms, and VPM +3 makes me feel the best. Including a lot of nitrox dives. Please don't tell me I'm wrong - or VPM isn't acccurate - because my selection doesn't match yours.

OK, let replace "accurate" by "adapted" (my english is not perfect, even if i have a lot of phone conferencing meetings with St-Louis, MO)
the V-Planner algorithm is based on decompression physics of deep dives with trimix, where the saturation/desaturation is quicker, so the rules are not the same.
you're free of using V-Planner for air/nitrox dives, of course.
My "french" tables are longer than US Navy tables.
Of course, I'm using a dive computer( 2, in fact), and the director is actually a Suunto Vytec DS

 

[ianr33]

the V-Planner algorithm is based on decompression physics of deep dives with trimix, where the saturation/desaturation is quicker, so the rules are not the same.

That's just flat out wrong.

 

[lowviz]

That's just flat out wrong.

well yes, but it will be OK.

...//...the director is actually a Suunto Vytec DS

See.

 

[Jax]

the V-Planner algorithm is based on decompression physics of deep dives with trimix, where the saturation/desaturation is quicker, so the rules are not the same.
you're free of using V-Planner for air/nitrox dives, of course.

On what did you base this? I have not heard it before.

 

[lowviz]

-simultaneous post, ya wanna flip for which issue goes first?

 

[flots am]

I am wondering how can you accidentally go into deco?

The very same way people "accidentally" run out of gas, drive over the lawn mower and bounce checks: by being oblivious to important information.

Accidental deco is an admission of either being completely oblivious to time and depth or being a thrill seeker and running the computer right up to the edge.

There's nothing wrong with planned deco. Accidental deco is an embarrassment and a safety hazard, since once you stop paying attention, there's little difference between incurring a 3 minute deco obligation and a 30 minute obligation.

flots