Chamber Dive & Computer Question.

[viceroy]

This weekend I did a chamber dive to a simulated 51m at an altitude of 1500m above sea-level, and had my Suunto Stinger with me.

The Stinger performed flawlessly during the dive, providing accurate information for every step of the dive, including deco stops which were never violated because the chamber operator was being extremely cautious and being even more conservative than the already conservative computer.

I'd like to know why the computer said it would be ok do do an 18m dive for 21 minutes immediately after this "extreme exposure" dive? Surely making any sort of dive after a 51m would be taking a big chance? Surely the computer has been built to be as safe as possible?

If anyone would like to reply, I'd really appreciate it

 

[Frog]

Hmmm I would really like to know the answer to this one because i was "going" to buy a Stinger in a few weeks time.
Viceroy did you adjust the computer to the altitude? or maybe i misunderstood you.

 

[turnerjd]

Originally posted by viceroy
I'd like to know why the computer said it would be ok do do an 18m dive for 21 minutes immediately after this "extreme exposure" dive? Surely making any sort of dive after a 51m would be taking a big chance? Surely the computer has been built to be as safe as possible?

51m is only an extreme exposure dive for US based agencies.

If you find any European tables (BSAC, FFESSM, Buhlman etc..) these all go below 50m. Now, the more important questions are

1) what was you first dive profile? what were the stops (if any)?

2) what algorithm is the stinger using? Buhlman 6 tissue?

3) what was the exact planned second dive?

With all this, look up the original tables / algorithms used in the stinger, and see if the profile is allowed. I suspect that you will find that for a square profile second dive 21 mins is a LOT less than you would be allowed if it was a first dive, and is possibly allowed by some sets of tables.

I will look this up on the BSAC tables and FFESSM tonight.

Jon T

 

[scubakat]

May I be so nosey to ask how you snagged a ride in the chamber?

-kate

 

[viceroy]

Well to ty answer all the questions.

1.) I did adjust the Stinger for altitude

2.) the dive profile was as follows:
- surface to 51m in 3 minutes
- total bottom time was 4 minutes
- steady surfacing speed of under 10m/min to 9m
- stopped at 9m for 5 minutes
- stopped at 6m for 5 minutes
- stopped at 4m for 5 minutes
- stopped at 2m for 15 minutes

total bottom time was 52minutes

3.) the stinger uses the Suunto Reduced Gradient Algorithm which I believe is based on Buhlman 6 tissue. I could be mistaken

4.) just out of curiosity I checked the stingers dive planner which showed a square profile dive of 18m for 21 minutes would be ok.

5.) as for how I snagged a ride in the chamber...I belong to a dive club and it was organised through them with a professional diving outfit. not a bad experience for R100 (approx. $13)

if you have any more questions...I'll be happy to try answer them

 

[scub dude]

Hey Viceroy... you said R100 - ie in South Africa? Whereabouts was this? I've done a chamber dive in Jet Park, Gauteng before (took my then Suunto Solution along for the trip). I now own a Stinger titanium... great computer/watch - just I'm stuck in the UK at the moment ... and not much chance of me getting in this cold water!

 

[viceroy]

Heyya Scubadude.

Did the chamber dive at Bass Lake.

 

[scub dude]

howdy...

was the chamber the one belonging to Professional Dive Center - Grant & his guys? If so... that's the one I did it in too.

What club do you belong to that arranged this?

 

[viceroy]

yeah...thats them.

I'm part of Diversity...not a big club...but definately fun

 

[Heads Up]

Originally posted by scubadude
Hey Viceroy... you said R100 - ie in South Africa? Whereabouts was this? I've done a chamber dive in Jet Park, Gauteng before (took my then Suunto Solution along for the trip). I now own a Stinger titanium... great computer/watch - just I'm stuck in the UK at the moment ... and not much chance of me getting in this cold water!

GET YER FINS WET!!

As for being 'stuck in the UK'?? Some of us have to LIVE here!! (hehe)