|
|
28-12-2011, 15:48
|
#46
|
Registered User
Join Date: Jan 2011
Posts: 267
|
Re: Rebreathers for Beginners ?
Quote:
Originally Posted by s/v Beth
As a anesthesiologist and a diver, I can tell you that we can monitor CO2 levels, I do it every day. We can also monitor blood SaO2 levels and blood (not just expired air) C02 levels. I run a closed circuit 5 or more times a day, thousand plus in a year. The problem is technology has not been completely and safely transported to Diving (yet). When it does, and has a safe track record, I'll be there.
|
Monitoring CO2 at ambient isn't such a big deal but monitoring in a variable pressure high humidity environment is proving to be a real challenge, very few RB manufacturers have even attempted, let alone worked out how to do it yet.
|
|
|
29-12-2011, 08:31
|
#47
|
Registered User
Join Date: Jul 2010
Location: East Tennessee
Boat: 1989 50 ft Roberts
Posts: 859
|
Re: Rebreathers for Beginners ?
...and this is the scary part to me. Putting in a co2 scrubber that "should" do the job worries me.
|
|
|
07-01-2012, 23:43
|
#48
|
Registered User
Join Date: Nov 2011
Location: Chattanooga Tennessee
Posts: 4
|
Re: Rebreathers for Beginners ?
From my experience SSI will set standards that X amount of dives will have been done and prerequisite classes before that. If that doesn't weed out the crowd then the $$ will. The industrys way of saying you don't have to be a Navy SEAL to experience a rebreather. I think it is a good idea. I love the idea that i can dive within recreational depth limits and not run out of air before I run out of time. It sucks to have to end a dive after a hour and a half because your low on air. Matt keep me posted and maybe I'll see you at the shop sometime.
|
|
|
08-01-2012, 03:38
|
#49
|
Registered User
Join Date: Apr 2011
Location: NZ
Boat: S34 Bob Stewart - 1959 Patiki class. Re--built by me & good mate.
Posts: 1,109
|
Re: Rebreathers for Beginners ?
I failed an oxygen tolerance test many moons ago for sat diving.
18mins at 66' (3bar ab) put me into convulsions, pissed my pants & gave me amnesia.
A couple of days in the navy hospital. I even got a general anesthetic, I guess to minimise effects. Weird, I remember the first tremor & anxiety & trying to crawl up the chamber wall, some frantic expletives from the two monitors, and then nothing
until fog lifted some time(?) later. Incessant repeditive questions- what is your name- where do you live-
IMHO, Oxygen poisoning is not to be trifled with. I still don't think its is completely understood; whether it is the inability of the body to deal with the volume of oxy free radicals attacking the cns, associated with higher partial pressures of O2, or whatever, it can onset very fast as I have experienced.
That said I would do training in a heart beat, to experience being bubble free.
If someone else pays!
|
|
|
08-01-2012, 04:23
|
#50
|
Registered User
Join Date: Feb 2010
Location: London, Ontario
Boat: Hunter 340
Posts: 637
|
Re: Rebreathers for Beginners ?
Quote:
Originally Posted by Matt sachs
|
Personally as a retired commercial diver, I think it's just plain dangerous and an immense amount of cash to blow.
|
|
|
08-01-2012, 05:02
|
#51
|
Registered User
Join Date: Dec 2010
Location: Western Caribbean
Boat: 38/41 Fountains pajot
Posts: 3,060
|
Re: Rebreathers for Beginners ?
Make your own for $100. 100 DOLLAR REBREATHER
Theres a video of him using it, but the pics at the bottom say enough.
Not sure if I have the Cojones for it though.,...though the idea of a rebreather on a sailboat vs heavy tanks is nice. Somedays I just dont feel like free diving.
|
|
|
11-01-2012, 07:56
|
#52
|
Registered User
Join Date: Jan 2011
Location: PNW
Boat: custom teak ketch 48' Eastwind
Posts: 607
|
Re: Rebreathers for Beginners ?
Thanks, I think I'll stick with my Kirby.
|
|
|
11-01-2012, 10:51
|
#53
|
Registered User
Join Date: Jul 2010
Location: East Tennessee
Boat: 1989 50 ft Roberts
Posts: 859
|
Re: Rebreathers for Beginners ?
Lateral, wow 3 ATA on O2? I bet that was an interesting hit. Our students don't breath O2 below 20 feet, and then, only at rest. We use 50% O2 down to 70feet, again, only while hanging out for deco. At depth, during the work phase of the dive, we dont exceed a PpO2 of 1.4.
My Mark VI discovery (that was delivered today, woo hoo) maintains a Po2 around 1.2 independant of depth. This is going to be really cool.
|
|
|
11-01-2012, 11:17
|
#54
|
Moderator
Join Date: Aug 2009
Location: Solent, England
Boat: Moody 31
Posts: 18,423
|
Re: Rebreathers for Beginners ?
Quote:
Originally Posted by lateral
I failed an oxygen tolerance test many moons ago for sat diving.
18mins at 66' (3bar ab) put me into convulsions, pissed my pants & gave me amnesia.
A couple of days in the navy hospital. I even got a general anesthetic, I guess to minimise effects. Weird, I remember the first tremor & anxiety & trying to crawl up the chamber wall, some frantic expletives from the two monitors, and then nothing
until fog lifted some time(?) later. Incessant repeditive questions- what is your name- where do you live-
IMHO, Oxygen poisoning is not to be trifled with. I still don't think its is completely understood; whether it is the inability of the body to deal with the volume of oxy free radicals attacking the cns, associated with higher partial pressures of O2, or whatever, it can onset very fast as I have experienced.
That said I would do training in a heart beat, to experience being bubble free.
If someone else pays!
|
There is a very interesting book called Oxygen and the diver by Kenneth Donald now sadly out of print and each copy worth a fortune. I was lucky enough to find a copy in a library. However, he discusses the RN attempts to find the limits of oxygen breathed underwater. Volunteers breathed pure oxygen at a variety of depths including 90m for 10 seconds. The result was there was no common denominator to establishing oxygen toxicity limits either between divers or even divers being test on different days. Fascinating and a horrifying read.
http://www.frogkick.nl/files/oxygen_and_the_diver.pdf
|
|
|
11-01-2012, 11:33
|
#55
|
Registered User
Join Date: Apr 2011
Location: NZ
Boat: S34 Bob Stewart - 1959 Patiki class. Re--built by me & good mate.
Posts: 1,109
|
Re: Rebreathers for Beginners ?
"Lateral, wow 3 ATA on O2? I bet that was an interesting hit. "
That was thirty years ago. As you probably are aware oxygen tolerance tests have long been disgarded. Too many many candidates succumbing at 100% O2.
Very cool unit unit you have. No doubt you will treat it with the respect it deserves.
|
|
|
11-01-2012, 12:38
|
#56
|
Registered User
Join Date: Jul 2010
Location: East Tennessee
Boat: 1989 50 ft Roberts
Posts: 859
|
Re: Rebreathers for Beginners ?
Quote:
Originally Posted by lateral
"Lateral, wow 3 ATA on O2? I bet that was an interesting hit. "
That was thirty years ago. As you probably are aware oxygen tolerance tests have long been disgarded. Too many many candidates succumbing at 100% O2.
Very cool unit unit you have. No doubt you will treat it with the respect it deserves.
|
Yes sir, I will.
|
|
|
11-01-2012, 15:32
|
#57
|
Registered User
Join Date: Feb 2010
Location: London, Ontario
Boat: Hunter 340
Posts: 637
|
Re: Rebreathers for Beginners ?
Good plan!
|
|
|
16-01-2012, 10:47
|
#58
|
Registered User
Join Date: Jul 2010
Location: East Tennessee
Boat: 1989 50 ft Roberts
Posts: 859
|
Re: Rebreathers for Beginners ?
After spending 10 hours in the class room yesterday, I have to say that this rebreather IS suited for certain beginner divers. This unit is unique in that it does a hyperoxic linearity test (It tests the o2 sensors to a Ppo2 of 1.6 the others only test up to a Ppo2 of 1.0) and throughout the dive plots a regression curve on the o2 sensors. Then it gives you a confidence level of those sensors. If anything goes wrong, depending on what it is, you will get a signal and instructions as to how to fix it, or to abort and go to open circuit.
This unit is intended for 100 feet, non decompression dives, it has 2 types of bail out, a heads up display, tactile and visual alerts and an LED display that displays all your dive parameters.
It is still a rebreather so Co2 is a concern. This unit uses a prepacked canister that will work at 4F for a minimum of 4 hours under heavy work conditions. The students are instructed to replace the canisters every 3 hours.
If the diver follows the training I feel these things are very safe. However if a student decides to come up with a "better" way or ignors the training, then ANY rebreather will kill you.
It's not for everybody, but I'm a happy customer.
|
|
|
16-01-2012, 18:11
|
#59
|
Senior Cruiser
Join Date: Oct 2007
Location: 29° 49.16’ N 82° 25.82’ W
Boat: Pearson 422
Posts: 16,306
|
Re: Rebreathers for Beginners ?
Quote:
Originally Posted by Matt sachs
This unit is intended for 100 feet, non decompression dives.
|
I really can't see why you would need a rebreather for 100' non deco dive. A single Al 80 does that job quite well for a fraction of the cost and a fraction of the complexity and risk.
__________________
The water is always bluer on the other side of the ocean.
Sometimes it's necessary to state the obvious for the benefit of the oblivious.
Rust is the poor man's Loctite.
|
|
|
16-01-2012, 23:29
|
#60
|
Registered User
Join Date: Sep 2009
Location: on board, Australia
Boat: 11meter Power catamaran
Posts: 3,648
|
Re: Rebreathers for Beginners ?
Quote:
Originally Posted by skipmac
I really can't see why you would need a rebreather for 100' non deco dive. A single Al 80 does that job quite well for a fraction of the cost and a fraction of the complexity and risk.
|
Decompression similarly is easily managed at that depth.
|
|
|
|
|
Thread Tools |
Search this Thread |
|
|
Display Modes |
Rate This Thread |
Linear Mode
|
|
Posting Rules
|
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts
HTML code is Off
|
|
|
|
Advertise Here
Recent Discussions |
|
|
|
|
|
|
|
|
|
|
|
|
Vendor Spotlight |
|
|
|
|