BOV Ever Used in Anger?

viscya · 1st April 2007, 00:59

I over breathed the loop during excess work load. Bail out went by the book.

Switch BOV
take a breath or two while deploying bailout reg.
switch to off board bailout.

Thank instructors for great training (JasonF/Dantheman)!

laurawood · 1st April 2007, 08:06

My view is that the fact you need two hands to close the inspo mouth piece is a major disavantage. At the time you come off the loop in my view you are likely to be under stress and are likely to be in need of the spare hand. I bailed out recently to OC on the surface after electronics failure and not knowing whether my mix was hypoxic. ie getting known OC gas in my mouth was the major concern. Flooding the loop and sinking was not. Personally I think that having something where you can shut the loop and very quickly get 1 or two mouthfuls of know gas would be great. I always have my main bailout round my neck any way & would look at switching so I had a decent amount of bail out & minimum stress. I know that alternative bail out methods on closed circuit are available but why ever use them if you carry OC bail out in the 1st place? The other angle is that I have 20 years open circuit experience & reflexes (& only 1 on CC) so to bail to open circuit when under stress would be a safer option in my opinion.

Ivon · 1st April 2007, 10:29

The tread is going off target as usual, it's not about the pros and cons of a BOV, the fact that you have 20 years of OC diving doesn't mean jack, if you have a bad hit you physically won't be able to go OC, period. You can argue this until your blue in the face, and if you try it you will know doubt end up that way!

What I would like to know is how had people have found turning the knob and going OC with the BOV in there mouth after a hit.

Personally after my hit I'm not 100% convinced I could have done this when I wanted to, but the switch to OC would have been easier after I'd gone open loop, plus the danger of taking the DSV out of your mouth and involuntarily breathing is removed.

watalibi · 1st April 2007, 10:58

Quote: (Originally Posted by nigelh)

This thread is going the way they usually do.

The people who have had CO2 hits think BOVs are manna sent from God.

Those that haven't can't see the point. "Just swap regs. It's easy isn't it?"

I can't agree more.
After the first real CO2 hit you know that you are not able to remove anything from your mouth when it happens (In almost 30 years of diving I experienced OC and CC CO2 hits).
A BOV on a CC allows you two things in one 1/4 turn with one hand:
- first you breathe good gas
- and first also you close your loop.

Safe dives.

Stéphane Havard
accueil watalibi

jptaylor9 · 1st April 2007, 11:15

Is a BOV the solution to concerns about CO2 hits, or should you examine/change your diving practices?

The following is specifically about the Inspiration (what I dive) & to my mind suggests that correct prep & maintainance of the unit is the best approach.

Although I haven't had a CO2 hit, I have flooded the scrubber & had a diluent leak that de-stabilized the set point; both were my fault & avoidable.

Quote: (Originally Posted by Martin Parker / Inspiration List Posting)

I've had many people talk to me about CO2 hits and in the end they came down to the following issues:

1) one was spending 20 mins packing his scrubber and created channelling and complained of CO2 hits at 75m with very moderate breathing rates - I have hit the canister with 105 lpm breathing rate and associated CO2 production at 75m and there is no immediate breakthrough.The scrubber didn't last as long as it does at the lower breathing rates, it lasted about 35 mins from memory but there was no premature breakthrough - nothing.

2) another fitted another brand of mouthpiece which allowed the teeth to close down more and restrict the breathing - retained CO2.

3) others have fitted VR3 Y pieces but not shortened the hose and so it kinks - again creating breathing resistance

4) others have simply over-used the canister, they are expecting 3 hours out of it and do all sorts of strange things like count only the time they are at depth, as if the time in the shallows doesn't count

5) one group were taught by a well known instructor to empty the contents of the scrubber out, break up the lumps and refill the canister ( now there is no longer a clear bed of unused lime), the incident that followed was filmed by an ROV and was then subject to a HSE investigation which is sort of still ongoing - I understand they are not prosecuting but they are trying to make it into a video.

6) mouthpiece valves leaking

7) the O ring on the scrubber cartridge does need to be lubricated

8) damaged components - the spacer ring needs turning over to ensure a clean, good side, is against the O ring if damaged on both sides, it'll need replacing.

9) I've had several say they used to get headaches on every dive, changed to a loose fill and the headaches disappeared.

JT

Gobfish1 · 1st April 2007, 12:49

Quote: (Originally Posted by laurawood)

My view is that the fact you need two hands to close the inspo mouth piece is a major disavantage. At the time you come off the loop in my view you are likely to be under stress and are likely to be in need of the spare hand. I bailed out recently to OC on the surface after electronics failure and not knowing whether my mix was hypoxic. ie getting known OC gas in my mouth was the major concern. Flooding the loop and sinking was not. Personally I think that having something where you can shut the loop and very quickly get 1 or two mouthfuls of know gas would be great. I always have my main bailout round my neck any way & would look at switching so I had a decent amount of bail out & minimum stress. I know that alternative bail out methods on closed circuit are available but why ever use them if you carry OC bail out in the 1st place? The other angle is that I have 20 years open circuit experience & reflexes (& only 1 on CC) so to bail to open circuit when under stress would be a safer option in my opinion.

sorry off post ,
next time stay on the loop and wack some o2 in , ( 1 year CC and 25 OC )

**Dave Sutton** · 1st April 2007, 13:41

Quote: (Originally Posted by nigelh)

This thread is going the way they usually do. The people who have had CO2 hits think BOVs are manna sent from God. Those that haven't can't see the point. "Just swap regs. It's easy isn't it?"

Yup.

In the event of a real C02 hit, as those of us who have suffered them can tell the others, all intellectual interaction with the situation ends so friggin' fast that it's scary. You *will not be willing* to take out your DSV and switch. You cannot simulate this, and you cannot learn it an easy way. It's TERRIFYING. I'll say this again: YOU WILL NOT BE WILLING TO REMOVE THE DSV FROM YOUR MOUTH. Example: I had a guy on the surface undergoing a C02 hit. He was *literally* dying on the surface. He has a good set of wings, and a good suit. His head was *above water*. All he had to do was to fill the wings and spit out the DSV. We had not less than 5 people shouting at him to do so. I looked him in the eyes (he made eye contact with me), and very slowly yelled *FILL YOUR WINGS AND SPIT OUT THE DSV*. A moment later he went limp and started sinking. He was at 10 feet and sinking when I collared him (fully clothed, mind you) and dragged him to the surface. In the on-boat debrief that afternoon, I asked him why he didn't breathe surface air. His answer was that he had no clue, that his feeling was that he was suffocating and that there was NO WAY IN HELL that he would spit out the ONLY THING KEEPING HIM ALIVE (even though it was *exactly* what was killing him). This is a classic human factor. It's predictable. You can deny it, but you'll probobably act the same way under the same circumstance. Better to simply accept it as a human factor and then remediate the risk by using the proper kit.

BOV's are an essential piece of kit. It's like an aerobatic pilots parachute. You can debate the good/bad before you fly all you like, but those who have used them when they were needed don't ever debate it again. Those that didn't have them when they needed them? They are not here to tell us about it....

BOV's? Use one.

Dave

Mdemon · 1st April 2007, 14:16

Quote: (Originally Posted by jptaylor9)

Is a BOV the solution to concerns about CO2 hits, or should you examine/change your diving practices?

Change the "or" to an "and" and I think you'll have covered it. BOV's handle a multitude of situations of your making or not.

Quote: (Originally Posted by Dave Sutton)

BOV's? Use one.

Dave

Zackly.

Dutchy · 1st April 2007, 14:53

Quote: (Originally Posted by divelermentov)

Therefor if anyone has first hand experience this would be very much appreciated.

When my plate in my SK was mal-adjusted I had too little volume in counterlungs. It was fine until I exerted myself.
I remember the great relief of tuning the knob despite the poorer WOB that OC comes with. In the next two seconds it was tuned and I felt a lot better alhough still breathing fast and feeling nausious.
I surfaced still breathing fast. (It happened @ 6m) and doubt very much if I would have been able to switch to my bailout-reg instead of using the BOV...

HelenM · 1st April 2007, 15:52

Quote: (Originally Posted by jptaylor9)

Is a BOV the solution to concerns about CO2 hits, or should you examine/change your diving practices?

The following is specifically about the Inspiration (what I dive) & to my mind suggests that correct prep & maintainance of the unit is the best approach.

If that is the case, and the absolute answer to the issue, why are AP themselves developing a BOV?

Yes, what you say is correct - but there is more to the story than this. CO2 hits do happen, even when kit is meticulously prepared. When they happen, you will not be able to take the mouthpiece out of your mouth for long enough to bail out. I know this to be true. I had a reg in my hand. I knew I needed to bail out onto it. It was, however, physically impossible for me to do so.

I will steal a line from Benjamin Franklin, and say "experience is a dear teacher, but fools will learn at no other".

Entirely up to you, but if you ever have the misfortune to suffer a bad hit you are going to feel a real f***ing idiot for not listening to all the comments from those who have actually experienced this. I only hope that you manage to get out of it alive.

1st April 2007, 00:59	#21 (permalink)
viscya Wrecking Crew Current Rebreather/s: Classic Kiss Other Rebreather/s: Join Date: Oct 2005 Location: Marlton New Jersey Posts: 138	Re: BOV Ever Used in Anger? I over breathed the loop during excess work load. Bail out went by the book. Switch BOV take a breath or two while deploying bailout reg. switch to off board bailout. Thank instructors for great training (JasonF/Dantheman)! __________________ "There is nothing majestic or dignified about being left to silently rot and collapse under heaps of old fishing net forgotten and unappreciated in dark and unvisited waters." DrMike
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1st April 2007, 08:06	#22 (permalink)
laurawood New Member Current Rebreather/s: Inspiration Classic Other Rebreather/s: Join Date: Mar 2007 Location: Dorset Posts: 8	Re: BOV Ever Used in Anger? My view is that the fact you need two hands to close the inspo mouth piece is a major disavantage. At the time you come off the loop in my view you are likely to be under stress and are likely to be in need of the spare hand. I bailed out recently to OC on the surface after electronics failure and not knowing whether my mix was hypoxic. ie getting known OC gas in my mouth was the major concern. Flooding the loop and sinking was not. Personally I think that having something where you can shut the loop and very quickly get 1 or two mouthfuls of know gas would be great. I always have my main bailout round my neck any way & would look at switching so I had a decent amount of bail out & minimum stress. I know that alternative bail out methods on closed circuit are available but why ever use them if you carry OC bail out in the 1st place? The other angle is that I have 20 years open circuit experience & reflexes (& only 1 on CC) so to bail to open circuit when under stress would be a safer option in my opinion.
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1st April 2007, 10:29	#23 (permalink)
Ivon Custom Title Allowed! Current Rebreather/s: Inspiration Classic Other Rebreather/s: Join Date: Feb 2006 Location: Hull, East Yorkshire, England Posts: 318	Re: BOV Ever Used in Anger? The tread is going off target as usual, it's not about the pros and cons of a BOV, the fact that you have 20 years of OC diving doesn't mean jack, if you have a bad hit you physically won't be able to go OC, period. You can argue this until your blue in the face, and if you try it you will know doubt end up that way! What I would like to know is how had people have found turning the knob and going OC with the BOV in there mouth after a hit. Personally after my hit I'm not 100% convinced I could have done this when I wanted to, but the switch to OC would have been easier after I'd gone open loop, plus the danger of taking the DSV out of your mouth and involuntarily breathing is removed.
(Offline)

1st April 2007, 10:58	#24 (permalink)
watalibi New Member Current Rebreather/s: Inspiration Vision Megalodon Sport Kiss Other Rebreather/s: Inspiration Classic Evolution Join Date: Nov 2005 Location: France Posts: 42	Re: BOV Ever Used in Anger? Quote: (Originally Posted by nigelh) This thread is going the way they usually do. The people who have had CO2 hits think BOVs are manna sent from God. Those that haven't can't see the point. "Just swap regs. It's easy isn't it?" I can't agree more. After the first real CO2 hit you know that you are not able to remove anything from your mouth when it happens (In almost 30 years of diving I experienced OC and CC CO2 hits). A BOV on a CC allows you two things in one 1/4 turn with one hand: - first you breathe good gas - and first also you close your loop. Safe dives. Stéphane Havard accueil watalibi
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1st April 2007, 11:15	#25 (permalink)
jptaylor9 Member Current Rebreather/s: Inspiration Vision Other Rebreather/s: Inspiration Classic Join Date: Feb 2005 Location: London, UK Posts: 318	Re: BOV Ever Used in Anger? Is a BOV the solution to concerns about CO2 hits, or should you examine/change your diving practices? The following is specifically about the Inspiration (what I dive) & to my mind suggests that correct prep & maintainance of the unit is the best approach. Although I haven't had a CO2 hit, I have flooded the scrubber & had a diluent leak that de-stabilized the set point; both were my fault & avoidable. Quote: (Originally Posted by Martin Parker / Inspiration List Posting) I've had many people talk to me about CO2 hits and in the end they came down to the following issues: 1) one was spending 20 mins packing his scrubber and created channelling and complained of CO2 hits at 75m with very moderate breathing rates - I have hit the canister with 105 lpm breathing rate and associated CO2 production at 75m and there is no immediate breakthrough.The scrubber didn't last as long as it does at the lower breathing rates, it lasted about 35 mins from memory but there was no premature breakthrough - nothing. 2) another fitted another brand of mouthpiece which allowed the teeth to close down more and restrict the breathing - retained CO2. 3) others have fitted VR3 Y pieces but not shortened the hose and so it kinks - again creating breathing resistance 4) others have simply over-used the canister, they are expecting 3 hours out of it and do all sorts of strange things like count only the time they are at depth, as if the time in the shallows doesn't count 5) one group were taught by a well known instructor to empty the contents of the scrubber out, break up the lumps and refill the canister ( now there is no longer a clear bed of unused lime), the incident that followed was filmed by an ROV and was then subject to a HSE investigation which is sort of still ongoing - I understand they are not prosecuting but they are trying to make it into a video. 6) mouthpiece valves leaking 7) the O ring on the scrubber cartridge does need to be lubricated 8) damaged components - the spacer ring needs turning over to ensure a clean, good side, is against the O ring if damaged on both sides, it'll need replacing. 9) I've had several say they used to get headaches on every dive, changed to a loose fill and the headaches disappeared. JT
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1st April 2007, 12:49	#26 (permalink)
Gobfish1 Custom Title Allowed! Current Rebreather/s: Inspiration Classic Other Rebreather/s: Inspiration Classic Inspiration Vision Evolution Join Date: Apr 2005 Location: Manchester UK Posts: 363	Re: BOV Ever Used in Anger? Quote: (Originally Posted by laurawood) My view is that the fact you need two hands to close the inspo mouth piece is a major disavantage. At the time you come off the loop in my view you are likely to be under stress and are likely to be in need of the spare hand. I bailed out recently to OC on the surface after electronics failure and not knowing whether my mix was hypoxic. ie getting known OC gas in my mouth was the major concern. Flooding the loop and sinking was not. Personally I think that having something where you can shut the loop and very quickly get 1 or two mouthfuls of know gas would be great. I always have my main bailout round my neck any way & would look at switching so I had a decent amount of bail out & minimum stress. I know that alternative bail out methods on closed circuit are available but why ever use them if you carry OC bail out in the 1st place? The other angle is that I have 20 years open circuit experience & reflexes (& only 1 on CC) so to bail to open circuit when under stress would be a safer option in my opinion. sorry off post , next time stay on the loop and wack some o2 in , ( 1 year CC and 25 OC ) __________________ Steve G Apparently not the only gay diver in the village http://drinkingliberally.org/blogs/o...nzee-glock.gif http://www.scubatunes.com/audio/vol01/mp3/HiTech.mp3
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1st April 2007, 13:41	#27 (permalink)
Dave Sutton Diveshop of Horrors Current Rebreather/s: Sport Kiss MK 15.X rEvo Other CCR Azimuth Home Build Other Rebreather/s: Classic Kiss rEvo Other CCR Azimuth Home Build Join Date: Jun 2006 Location: Narragansett, Rhode Island and Hackettstown, New Jersey Posts: 2,672	Re: BOV Ever Used in Anger? Quote: (Originally Posted by nigelh) This thread is going the way they usually do. The people who have had CO2 hits think BOVs are manna sent from God. Those that haven't can't see the point. "Just swap regs. It's easy isn't it?" Yup. In the event of a real C02 hit, as those of us who have suffered them can tell the others, all intellectual interaction with the situation ends so friggin' fast that it's scary. You will not be willing to take out your DSV and switch. You cannot simulate this, and you cannot learn it an easy way. It's TERRIFYING. I'll say this again: YOU WILL NOT BE WILLING TO REMOVE THE DSV FROM YOUR MOUTH. Example: I had a guy on the surface undergoing a C02 hit. He was literally dying on the surface. He has a good set of wings, and a good suit. His head was above water. All he had to do was to fill the wings and spit out the DSV. We had not less than 5 people shouting at him to do so. I looked him in the eyes (he made eye contact with me), and very slowly yelled FILL YOUR WINGS AND SPIT OUT THE DSV. A moment later he went limp and started sinking. He was at 10 feet and sinking when I collared him (fully clothed, mind you) and dragged him to the surface. In the on-boat debrief that afternoon, I asked him why he didn't breathe surface air. His answer was that he had no clue, that his feeling was that he was suffocating and that there was NO WAY IN HELL that he would spit out the ONLY THING KEEPING HIM ALIVE (even though it was exactly what was killing him). This is a classic human factor. It's predictable. You can deny it, but you'll probobably act the same way under the same circumstance. Better to simply accept it as a human factor and then remediate the risk by using the proper kit. BOV's are an essential piece of kit. It's like an aerobatic pilots parachute. You can debate the good/bad before you fly all you like, but those who have used them when they were needed don't ever debate it again. Those that didn't have them when they needed them? They are not here to tell us about it.... BOV's? Use one. Dave __________________ "Changes in Lattitudes, Changes in Attitudes, Nothing remains quite the same".... www.nobubblediving.com
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1st April 2007, 14:16	#28 (permalink)
Mdemon SiegeEngine II Current Rebreather/s: Inspiration Classic Home Build Other Rebreather/s: Inspiration Classic Home Build Join Date: Feb 2007 Location: SWUK Posts: 1,927	Re: BOV Ever Used in Anger? Quote: (Originally Posted by jptaylor9) Is a BOV the solution to concerns about CO2 hits, or should you examine/change your diving practices? Change the "or" to an "and" and I think you'll have covered it. BOV's handle a multitude of situations of your making or not. Quote: (Originally Posted by Dave Sutton) BOV's? Use one. Dave Zackly.
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1st April 2007, 14:53	#29 (permalink)
Dutchy Rene Warries Current Rebreather/s: Sport Kiss Other Rebreather/s: Join Date: Apr 2006 Location: Nieuwegein (The Netherlands) Posts: 769	Re: BOV Ever Used in Anger? Quote: (Originally Posted by divelermentov) Therefor if anyone has first hand experience this would be very much appreciated. When my plate in my SK was mal-adjusted I had too little volume in counterlungs. It was fine until I exerted myself. I remember the great relief of tuning the knob despite the poorer WOB that OC comes with. In the next two seconds it was tuned and I felt a lot better alhough still breathing fast and feeling nausious. I surfaced still breathing fast. (It happened @ 6m) and doubt very much if I would have been able to switch to my bailout-reg instead of using the BOV... __________________ = This post is environmentally friendly. It is composed of 100% recycled electrons only. =
(Online)

1st April 2007, 15:52	#30 (permalink)
HelenM Custom Title Allowed! Current Rebreather/s: Inspiration Classic Other Rebreather/s: Join Date: Feb 2005 Location: Cheltenham Posts: 116	Re: BOV Ever Used in Anger? Quote: (Originally Posted by jptaylor9) Is a BOV the solution to concerns about CO2 hits, or should you examine/change your diving practices? The following is specifically about the Inspiration (what I dive) & to my mind suggests that correct prep & maintainance of the unit is the best approach. If that is the case, and the absolute answer to the issue, why are AP themselves developing a BOV? Yes, what you say is correct - but there is more to the story than this. CO2 hits do happen, even when kit is meticulously prepared. When they happen, you will not be able to take the mouthpiece out of your mouth for long enough to bail out. I know this to be true. I had a reg in my hand. I knew I needed to bail out onto it. It was, however, physically impossible for me to do so. I will steal a line from Benjamin Franklin, and say "experience is a dear teacher, but fools will learn at no other". Entirely up to you, but if you ever have the misfortune to suffer a bad hit you are going to feel a real f***ing idiot for not listening to all the comments from those who have actually experienced this. I only hope that you manage to get out of it alive. __________________ Would paper take tortoise?
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