Rebreather

silent running · 23rd February 2006, 09:53

Quote: (Originally Posted by Drmike)

I very much doubt the Boris scrubber is better or has longer duration than the MK15.5. I have done 11 hours on the MK15.5 - I am not expecting to be able to get that on Boris.

Very interesting Mike. Seems the MK 15.5 and the Prism have even more things in common than I thought...

silent running · 23rd February 2006, 10:08

Quote: (Originally Posted by caveseeker7)

That's one issue were both Meg and PRISM kinda suck in my opinion.

Stefan, how do they both suck and how hard? Are you thinking that it's possible to mix up the lp hoses? The Prism has a restrictor on the O2 lp hose, so I'm guessing that if someone were dumb enough to mix them up, the slow flow on descent to the adv would cause one to pause. Don't know about the Meg. Or do you just not like the gas flow direction on the units?
I'm OK with the Prism being counter clock as I'm right handed and feel the manual add dil/O2 is set up for easy right hand access.

Nad · 23rd February 2006, 11:24

Quote: (Originally Posted by Drmike)

1) -I can dive sub 170m without the buzzer flooding and destroying the electronic control
2) -I can still read my PPO2 and run the unit manually even if the primary electronics fail
3) -I can crawl through sharp wrecks/cave without fear of cutting the counterlungs
4) -I can plug in off board O2 and dil and it will run of them automatically (not me doing manual injections)
5) -I can do a dive longer that a few hours without condensation destroying my life support ppo2 sensor outputs (to be confirmed)
6) -I dont have to replace the rusted out Inspiration handset magnets every month (older model)
7) -If displays fail or subsystems flood I have 4 means to know my ppoo2

Thanks Mike, you saved me the work to write.

Hey Nick, that's enough?

Nad

Drmike · 23rd February 2006, 11:50

I very much doubt it makes a difference where the O2 is injected from a ppo2 safety/oxtox viewpoint. The small amount of O2 goes into a CL full of dil and so the ppo2 'spike' is reduced then, the gas will mix on the first breath and as you never fully evacuate your lungs when you breath the ppo2 'spike' in the lung will be further reduced by the residual gas volume in there.

We can safely breathe very high ppo2s for very short periods of time (seconds) without risk of toxing* - so I doubt the single breath momentary spike after its been reduced in magnitude by the CL vol, lung vol etc is really an issue at all.

(* I was given info from DrBH that in tests 11bar of O2 for 25 secs at a time did not induce toxing - I dont as yet have a copy of test report)

Nick uk. · 23rd February 2006, 12:11

Quote: (Originally Posted by Nad)

Thanks Mike, you saved me the work to write.

Hey Nick, that's enough?

Nad

You'll have give me a closer look at the Eudi show.

***caveseeker7*** · 23rd February 2006, 19:16

Quote: (Originally Posted by silent running)

Stefan, how do they both suck and how hard? Are you thinking that it's possible to mix up the lp hoses?

Accidently mixing up hoses isn't the issue, I doubt the dil hose could reach the O2 add valve in the first place. By the way, you don't want to plug the O2 hose into the ADV.

They suck by breaking with conventions.

Usually the rich mix (O2) is right, the lean mix is left.
On every unit I can think of with exception of the PRISM.

(Realize early CK had that too, but Gordon fixed that

)
If you dive more than one Rebreather you have to adjust, so does everyone around you who isn't a PRISM diver. Not huge, but not necessary either as seen on MK, Shadow Pack and Ouroboros rebreathers.

Same with the Meg, only unit I can think of that injects any O2 after the sensors. Just doesn't seem like a wise decision, which is probably the reason no one else does it. Using it yourself is not an issue, you'll get the hang of where to push.

Crossing hoses on purpose breaks the convention of having an O2 side and a dil side on your Rebreather. You'll add O2 on the left and fiddle with the O2 valve on the right. Again, not a big issue, certainly not if it's your rig and you're accustomed to it.

There aren't standards in that regard that manufacturer's have to follow, but there are conventions and common sense that I don't see a reason to break with.

Nad · 23rd February 2006, 23:21

Quote: (Originally Posted by Nick uk.)

You'll have give me a closer look at the Eudi show.

Ooooooooooooooooooook.

Nad

Yessic · 23rd February 2006, 23:39

Quote: (Originally Posted by Drmike)

I have done 11 hours on the MK15.5.

DrMike,

Where did you dive the MK15.5 for 11 hours? How deep, what was the deco like?

Yessic

silent running · 24th February 2006, 00:39

Quote: (Originally Posted by caveseeker7)

Accidently mixing up hoses isn't the issue, I doubt the dil hose could reach the O2 add valve in the first place. By the way, you don't want to plug the O2 hose into the ADV.

They suck by breaking with conventions.

Usually the rich mix (O2) is right, the lean mix is left.
On every unit I can think of with exception of the PRISM.

(Realize early CK had that too, but Gordon fixed that

)
If you dive more than one Rebreather you have to adjust, so does everyone around you who isn't a PRISM diver. Not huge, but not necessary either as seen on MK, Shadow Pack and Ouroboros rebreathers.

Same with the Meg, only unit I can think of that injects any O2 after the sensors. Just doesn't seem like a wise decision, which is probably the reason no one else does it. Using it yourself is not an issue, you'll get the hang of where to push.

Crossing hoses on purpose breaks the convention of having an O2 side and a dil side on your Rebreather. You'll add O2 on the left and fiddle with the O2 valve on the right. Again, not a big issue, certainly not if it's your rig and you're accustomed to it.

There aren't standards in that regard that manufacturer's have to follow, but there are conventions and common sense that I don't see a reason to break with.

Stefan, I understand the part about conventions and using more than 1 Rebreather. But don't you think there's some value in having the manual add buttonson the Prism setup to be easily reached with the right hand when most people are right handed? It probably gets the muscle memory happening faster...(no offense meant to the leftys) I'm pretty sure this was the reason given to me by Peter when I asked why he reversed the flow. -Andy

**trob09** · 24th February 2006, 01:09

Quote: (Originally Posted by caveseeker7)

Same with the Meg, only unit I can think of that injects any O2 after the sensors. Just doesn't seem like a wise decision, which is probably the reason no one else does it. Using it yourself is not an issue, you'll get the hang of where to push.

Stefan,

Just a small point of clarification here, the Meg injects O2 from the solenoid before the scrubber and sensors. The manual add is after the sensors. (I think that's what you meant, but I'm not sure)

You can (and I have seen several do this - tried it myself for a while) plumb the O2 manual add to the exhale counter lung if ox-tox is a concern.

Tim

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23rd February 2006, 09:53	#31 (permalink)
silent running Mature mouth breather Current Rebreather/s: Prism Topaz Other Rebreather/s: Join Date: Jun 2005 Location: U.S.A. Brooklyn, New York Posts: 1,813	Re: Rebreather Quote: (Originally Posted by Drmike) I very much doubt the Boris scrubber is better or has longer duration than the MK15.5. I have done 11 hours on the MK15.5 - I am not expecting to be able to get that on Boris. Very interesting Mike. Seems the MK 15.5 and the Prism have even more things in common than I thought...
(Online)

23rd February 2006, 10:08	#32 (permalink)
silent running Mature mouth breather Current Rebreather/s: Prism Topaz Other Rebreather/s: Join Date: Jun 2005 Location: U.S.A. Brooklyn, New York Posts: 1,813	Re: Rebreather Quote: (Originally Posted by caveseeker7) That's one issue were both Meg and PRISM kinda suck in my opinion. Stefan, how do they both suck and how hard? Are you thinking that it's possible to mix up the lp hoses? The Prism has a restrictor on the O2 lp hose, so I'm guessing that if someone were dumb enough to mix them up, the slow flow on descent to the adv would cause one to pause. Don't know about the Meg. Or do you just not like the gas flow direction on the units? I'm OK with the Prism being counter clock as I'm right handed and feel the manual add dil/O2 is set up for easy right hand access.
(Online)

23rd February 2006, 11:24	#33 (permalink)
Nad Rebel to the Bone Current Rebreather/s: Ouroboros Other Rebreather/s: Not Bought Yet Inspiration Classic Join Date: Mar 2005 Location: Europe Posts: 960	Re: Rebreather Quote: (Originally Posted by Drmike) 1) -I can dive sub 170m without the buzzer flooding and destroying the electronic control 2) -I can still read my PPO2 and run the unit manually even if the primary electronics fail 3) -I can crawl through sharp wrecks/cave without fear of cutting the counterlungs 4) -I can plug in off board O2 and dil and it will run of them automatically (not me doing manual injections) 5) -I can do a dive longer that a few hours without condensation destroying my life support ppo2 sensor outputs (to be confirmed) 6) -I dont have to replace the rusted out Inspiration handset magnets every month (older model) 7) -If displays fail or subsystems flood I have 4 means to know my ppoo2 Thanks Mike, you saved me the work to write. Hey Nick, that's enough? Nad __________________ The Impossible is often the Untried
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23rd February 2006, 11:50	#34 (permalink)
Drmike Custom Title Allowed! Current Rebreather/s: MK 15.X Ouroboros Other CCR Home Build Other Rebreather/s: Inspiration Classic Other CCR Home Build Join Date: Feb 2005 Posts: 3,157	Re: Rebreather I very much doubt it makes a difference where the O2 is injected from a ppo2 safety/oxtox viewpoint. The small amount of O2 goes into a CL full of dil and so the ppo2 'spike' is reduced then, the gas will mix on the first breath and as you never fully evacuate your lungs when you breath the ppo2 'spike' in the lung will be further reduced by the residual gas volume in there. We can safely breathe very high ppo2s for very short periods of time (seconds) without risk of toxing* - so I doubt the single breath momentary spike after its been reduced in magnitude by the CL vol, lung vol etc is really an issue at all. (* I was given info from DrBH that in tests 11bar of O2 for 25 secs at a time did not induce toxing - I dont as yet have a copy of test report) __________________ Cave diving is a sport Wreck diving is a sport Diving in general is a sport 'Rebreather diving' is not a sport its the delusional obsession with a highly dangerous and often inappropriate piece of equipment
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23rd February 2006, 12:11	#35 (permalink)
Nick uk. Made in England. Current Rebreather/s: Inspiration Classic Azimuth Other Rebreather/s: Azimuth Join Date: Nov 2005 Location: Viale C.Colombo 75 Marina di Carrara. MS 54036 Italy Posts: 579	Re: Rebreather Quote: (Originally Posted by Nad) Thanks Mike, you saved me the work to write. Hey Nick, that's enough? Nad You'll have give me a closer look at the Eudi show. __________________ If it aint broke....don't fix it, and if it is.............well......get another one! divechief2000@hotmail.com
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23rd February 2006, 19:16	#36 (permalink)
*caveseeker7* Who loves ya, baby Current Rebreather/s: Sport Kiss Other Rebreather/s: Prism Topaz Join Date: Jan 2005 Location: Too far from Neverland Posts: 5,435	Re: Rebreather Quote: (Originally Posted by silent running) Stefan, how do they both suck and how hard? Are you thinking that it's possible to mix up the lp hoses? Accidently mixing up hoses isn't the issue, I doubt the dil hose could reach the O2 add valve in the first place. By the way, you don't want to plug the O2 hose into the ADV. They suck by breaking with conventions. Usually the rich mix (O2) is right, the lean mix is left. On every unit I can think of with exception of the PRISM. (Realize early CK had that too, but Gordon fixed that ) If you dive more than one Rebreather you have to adjust, so does everyone around you who isn't a PRISM diver. Not huge, but not necessary either as seen on MK, Shadow Pack and Ouroboros rebreathers. Same with the Meg, only unit I can think of that injects any O2 after the sensors. Just doesn't seem like a wise decision, which is probably the reason no one else does it. Using it yourself is not an issue, you'll get the hang of where to push. Crossing hoses on purpose breaks the convention of having an O2 side and a dil side on your Rebreather. You'll add O2 on the left and fiddle with the O2 valve on the right. Again, not a big issue, certainly not if it's your rig and you're accustomed to it. There aren't standards in that regard that manufacturer's have to follow, but there are conventions and common sense that I don't see a reason to break with. __________________ Cheers Stefan "Political Correctness is a doctrine, fostered by a delusional, illogical minority, and rabidly promoted by an unscrupulous mainstream media, which holds forth the proposition that it is entirely possible to pick up a turd by the clean end.'!"
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23rd February 2006, 23:21	#37 (permalink)
Nad Rebel to the Bone Current Rebreather/s: Ouroboros Other Rebreather/s: Not Bought Yet Inspiration Classic Join Date: Mar 2005 Location: Europe Posts: 960	Re: Rebreather Quote: (Originally Posted by Nick uk.) You'll have give me a closer look at the Eudi show. Ooooooooooooooooooook. Nad __________________ The Impossible is often the Untried
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23rd February 2006, 23:39	#38 (permalink)
Yessic New Member Current Rebreather/s: Not Bought Yet Other Rebreather/s: Not Bought Yet Join Date: Jan 2006 Location: Tampa, FL Posts: 17	Re: Rebreather Quote: (Originally Posted by Drmike) I have done 11 hours on the MK15.5. DrMike, Where did you dive the MK15.5 for 11 hours? How deep, what was the deco like? Yessic Last edited by Yessic : 23rd February 2006 at 23:44.
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24th February 2006, 00:39	#39 (permalink)
silent running Mature mouth breather Current Rebreather/s: Prism Topaz Other Rebreather/s: Join Date: Jun 2005 Location: U.S.A. Brooklyn, New York Posts: 1,813	Re: Rebreather Quote: (Originally Posted by caveseeker7) Accidently mixing up hoses isn't the issue, I doubt the dil hose could reach the O2 add valve in the first place. By the way, you don't want to plug the O2 hose into the ADV. They suck by breaking with conventions. Usually the rich mix (O2) is right, the lean mix is left. On every unit I can think of with exception of the PRISM. (Realize early CK had that too, but Gordon fixed that ) If you dive more than one Rebreather you have to adjust, so does everyone around you who isn't a PRISM diver. Not huge, but not necessary either as seen on MK, Shadow Pack and Ouroboros rebreathers. Same with the Meg, only unit I can think of that injects any O2 after the sensors. Just doesn't seem like a wise decision, which is probably the reason no one else does it. Using it yourself is not an issue, you'll get the hang of where to push. Crossing hoses on purpose breaks the convention of having an O2 side and a dil side on your Rebreather. You'll add O2 on the left and fiddle with the O2 valve on the right. Again, not a big issue, certainly not if it's your rig and you're accustomed to it. There aren't standards in that regard that manufacturer's have to follow, but there are conventions and common sense that I don't see a reason to break with. Stefan, I understand the part about conventions and using more than 1 Rebreather. But don't you think there's some value in having the manual add buttonson the Prism setup to be easily reached with the right hand when most people are right handed? It probably gets the muscle memory happening faster...(no offense meant to the leftys) I'm pretty sure this was the reason given to me by Peter when I asked why he reversed the flow. -Andy
(Online)

24th February 2006, 01:09	#40 (permalink)
trob09 . Current Rebreather/s: Megalodon Other Rebreather/s: Join Date: Feb 2005 Posts: 698	Re: Rebreather Quote: (Originally Posted by caveseeker7) Same with the Meg, only unit I can think of that injects any O2 after the sensors. Just doesn't seem like a wise decision, which is probably the reason no one else does it. Using it yourself is not an issue, you'll get the hang of where to push. Stefan, Just a small point of clarification here, the Meg injects O2 from the solenoid before the scrubber and sensors. The manual add is after the sensors. (I think that's what you meant, but I'm not sure) You can (and I have seen several do this - tried it myself for a while) plumb the O2 manual add to the exhale counter lung if ox-tox is a concern. Tim
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