Possible C02 Hit?

jdicediver · 29th October 2007, 23:13

Quote: (Originally Posted by sunnyboy)

Pardon? Almost every person replying to your OP has stated they believe that you had a CO2 hit. Why are you not convinced you had a 'full blown' CO2 hit?

-S

1) I have never experienced one
2) The delayed headache
3) Denial, denial denial...'nuf said.

I maintain that it doesn't really matter, As previously stated, I have revised my procedures, and hopefully the banter will make others do likewise.

Quote: (Originally Posted by wedivebc)

Maybe like the lady who was only partially pregnant

Nope, that's not the case...I received the birth control from YOU, and there were no holes in the latex!

**wedivebc** · 29th October 2007, 23:29

Quote: (Originally Posted by jdicediver)

Nope, that's not the case...I received the birth control from YOU, and there were no holes in the latex!

OK you're just scaring me now

jdicediver · 29th October 2007, 23:31

Quote: (Originally Posted by wedivebc)

OK you're just scaring me now

LOL...admit it...I AM your most favorite student, righhhhttttt?

mattmexico · 30th October 2007, 00:10

yo

Some weeks ago I was asking some questions here on Rebreather World on how people practice or care for their partially spend absorbent materials in regards to potential re-use.

A lot replies came in they chuck it, period.

A lot of replies came in they bag it, so do I ... but what is the time limit. I always said no more then a couple of days but that certainly is emperical and not based on any science at all.

One reply came in explaining something about humidity needed to set of the chemical reaction and if bagging a partially used scrubber you have no humidity left to start propper chemical reaction .... no fuse so to speak .. or a very short one, depending on view point.

That really got me thinking. Am I making a large and huge mistake bagging my partially used scrubber .... and even worse, by telling other people, students, and do it in front of them in plain sight, explaining that is ok to do, am I setting people up for suicide missions ?.

That thought was and is sitting heavy on my shoulders. Maybe procedure should or need to be changed, or clearer stated, very clear, that it is not ok to re-use partially used scrubber material ... period.

I do not know but what I know is thanx to your report is it made me even more thinking .... and it aint hurt, the thinking part I mean ...

greetings
Matt

jdicediver · 30th October 2007, 02:00

Quote: (Originally Posted by mattmexico)

yo

Some weeks ago I was asking some questions here on Rebreather World on how people practice or care for their partially spend absorbent materials in regards to potential re-use.

A lot replies came in they chuck it, period.

A lot of replies came in they bag it, so do I ... but what is the time limit. I always said no more then a couple of days but that certainly is emperical and not based on any science at all.

One reply came in explaining something about humidity needed to set of the chemical reaction and if bagging a partially used scrubber you have no humidity left to start propper chemical reaction .... no fuse so to speak .. or a very short one, depending on view point.

That really got me thinking. Am I making a large and huge mistake bagging my partially used scrubber .... and even worse, by telling other people, students, and do it in front of them in plain sight, explaining that is ok to do, am I setting people up for suicide missions ?.

That thought was and is sitting heavy on my shoulders. Maybe procedure should or need to be changed, or clearer stated, very clear, that it is not ok to re-use partially used scrubber material ... period.

I do not know but what I know is thanx to your report is it made me even more thinking .... and it aint hurt, the thinking part I mean ...

greetings
Matt

Matt, I agree with you 133%. I do feel that the best procedure is to toss a can full of partially used 'sorb if it isn't used within a short period. Anyone would agree that this would be the wisest choice.

We all make decisions virtually daily that may indirectly affect the lives of others without having the slightest understanding of the amplitude or final impact of our statements having been heard. What is the reason some are elected within our political system and others are not?

How people interpret our sometimes verbose yet seemingly convincing comments is far beyond our comprehension. Take the word religious for example, throw it out there, and you will receive at least ten differing definitions from one room containing only eight people.

I have thought at times that an area that would be of benefit <although would take some time and work to develop and manage> and would prove to be functionally better than a "Search" function would be a FAQ section containing "Proven Majority Rules" If this idea is of slight interest, maybe a thread could be started regarding the possible development of same?

Let's face it, I think it has been said before...We are the Policy Makers...Let us not be wrong.

Dave O · 30th October 2007, 02:56

Quote: (Originally Posted by mattmexico)

yo

Some weeks ago I was asking some questions here on Rebreather World on how people practice or care for their partially spend absorbent materials in regards to potential re-use.

A lot replies came in they chuck it, period.

A lot of replies came in they bag it, so do I ... but what is the time limit. I always said no more then a couple of days but that certainly is emperical and not based on any science at all.

One reply came in explaining something about humidity needed to set of the chemical reaction and if bagging a partially used scrubber you have no humidity left to start propper chemical reaction .... no fuse so to speak .. or a very short one, depending on view point.

That really got me thinking. Am I making a large and huge mistake bagging my partially used scrubber .... and even worse, by telling other people, students, and do it in front of them in plain sight, explaining that is ok to do, am I setting people up for suicide missions ?.

That thought was and is sitting heavy on my shoulders. Maybe procedure should or need to be changed, or clearer stated, very clear, that it is not ok to re-use partially used scrubber material ... period.

I do not know but what I know is thanx to your report is it made me even more thinking .... and it aint hurt, the thinking part I mean ...

greetings
Matt

Matt,

This comes to mind

http://www.rebreatherworld.com/137949-post6.html

jdicediver · 30th October 2007, 03:19

Quote: (Originally Posted by Dave O)

Matt,

This comes to mind

http://www.rebreatherworld.com/137949-post6.html

To Plagiarize the contents of the above post for sake of timing:

Quote: (Originally Posted by Molecular Products Ltd)

The reaction sequence shown in your note is an oversimplification of the actual chemical reaction sequence that occurs. Sodium carbonate is not formed at the pH of the reactions, it is sodium bicarbonate that acts as the carrier molecule. A better description is:

Overall: CO2 + Ca(OH)2 => Ca(CO3) + H2O made up of the individual stages:

CO2 + H2O <=> CO2 in solution (it just dissolves - it does not form carbonic acid)

CO2 + NaOH => NaHCO2

NaHCO3 + Ca(OH)2 => Ca(CO3)2 + NaOH + H2O

The NaOH in stage 3 is recycled to stage 2 and behaves as a catalyst. It should also be noted that there is a net gain in water.
The overall reaction is not reversible under the conditions you describe and will not increase the capacity of the soda lime or allow it to be safely reused. Once soda lime has been left open or part used the water balance in the material is changed and the performance will be affected. Soda lime that is too dry or too wet will reduce the CO2 removal rate and place the diver at risk. It is not safe to keep part used soda lime for reuse for more than a few hours in your rebreather if it is to be again. This is because the water balance will start to redistribute and will adversely effect performance.

The thinking on redistribution is also not useful as even if the unit did become homogenous, (which it won’t) the capacity would still be less than if the unit was used all at one time. This is because the reaction zone would be larger and the effective capacity of the remaining unreacted material will therefore be reduced.

Hmmm...sobering information, from the manufacturer nonetheless. Pretty indisputable evidence I would have to say. I think this is the start of something good...

tibby · 30th October 2007, 12:43

Quote: (Originally Posted by Dave O)

Matt,

This comes to mind

http://www.rebreatherworld.com/137949-post6.html

That's it, I'm chucking mine from now on unless I'll use it the same day.

**Dsix36** · 30th October 2007, 21:48

Quote: (Originally Posted by Dave O)

Matt,

This comes to mind

http://www.rebreatherworld.com/137949-post6.html

How does this apply to an ExtendAir cartridge?

silent running · 31st October 2007, 05:53

Quote: (Originally Posted by mattmexico)

One reply came in explaining something about humidity needed to set of the chemical reaction and if bagging a partially used scrubber you have no humidity left to start propper chemical reaction .... no fuse so to speak .. or a very short one, depending on view point.

That really got me thinking. Am I making a large and huge mistake bagging my partially used scrubber .... and even worse, by telling other people, students, and do it in front of them in plain sight, explaining that is ok to do, am I setting people up for suicide missions ?.

That thought was and is sitting heavy on my shoulders. Maybe procedure should or need to be changed, or clearer stated, very clear, that it is not ok to re-use partially used scrubber material ... period.

I do not know but what I know is thanx to your report is it made me even more thinking .... and it aint hurt, the thinking part I mean ...

greetings
Matt

Hi Matt, the point about humidity being needed for sorb to start working/fuse analogy is a good one and valid. But, I think that any time you store partially used sorb in a bag, it will have a lot more moisture in it that when it comes out of the tub due to the rection being started. So much so that when I take a canister out to store overnight, I let it dry out in the air for a while to prevent clumping before putting it in the bag, it's that wet.

Now obviously 6 weeks is a long time and storing and/or using it in a cold place is not the same as bagging a scrubber for a few days in the tropics. But the principle is the same-everytime I have removed a scrubber it was much more moist than the stuff I filled it with out of the tub. If the ambient temp is high enough and the storage short enough, then reusing sorb shouldn't be a problem. But yes, it's still just a guess and who knows exactly where the line is, without some sort of expensive, time consuming tests? -Andy

29th October 2007, 23:13	#21 (permalink)
jdicediver Single/burdened with cash Current Rebreather/s: Megalodon Other Rebreather/s: Join Date: Jun 2006 Location: Calgary, Alberta Posts: 256	Re: Possible C02 Hit? Quote: (Originally Posted by sunnyboy) Pardon? Almost every person replying to your OP has stated they believe that you had a CO2 hit. Why are you not convinced you had a 'full blown' CO2 hit? -S 1) I have never experienced one 2) The delayed headache 3) Denial, denial denial...'nuf said. I maintain that it doesn't really matter, As previously stated, I have revised my procedures, and hopefully the banter will make others do likewise. Quote: (Originally Posted by wedivebc) Maybe like the lady who was only partially pregnant Nope, that's not the case...I received the birth control from YOU, and there were no holes in the latex! __________________ Regards; "Alterations performed under controlled conditions, on a closed course by a qualified Closed Circuit Diver" "Some people shouldn't dive...others shouldn't even get wet".
(Offline)

29th October 2007, 23:29	#22 (permalink)
wedivebc FIGJAM Current Rebreather/s: Megalodon Other CCR Other Rebreather/s: Not Bought Yet Inspiration Classic Sport Kiss Other CCR Join Date: Feb 2005 Location: Vancouver Island BC Canada Posts: 1,411	Re: Possible C02 Hit? Quote: (Originally Posted by jdicediver) Nope, that's not the case...I received the birth control from YOU, and there were no holes in the latex! OK you're just scaring me now __________________ Cheers, Dave.... Man is the only animal burdened with the knowledge he will eventually die
(Offline)

29th October 2007, 23:31	#23 (permalink)
jdicediver Single/burdened with cash Current Rebreather/s: Megalodon Other Rebreather/s: Join Date: Jun 2006 Location: Calgary, Alberta Posts: 256	Re: Possible C02 Hit? Quote: (Originally Posted by wedivebc) OK you're just scaring me now LOL...admit it...I AM your most favorite student, righhhhttttt? __________________ Regards; "Alterations performed under controlled conditions, on a closed course by a qualified Closed Circuit Diver" "Some people shouldn't dive...others shouldn't even get wet".
(Offline)

30th October 2007, 00:10	#24 (permalink)
mattmexico Rebreather World Writer Current Rebreather/s: Megalodon Classic Kiss Optima RB80 / Clone Other Rebreather/s: Inspiration Classic Evolution Prism Topaz Sport Kiss RB80 / Clone Join Date: Aug 2005 Location: Mexico, Q.Roo, Playa del Carmen Posts: 762	Re: Possible C02 Hit? yo Some weeks ago I was asking some questions here on Rebreather World on how people practice or care for their partially spend absorbent materials in regards to potential re-use. A lot replies came in they chuck it, period. A lot of replies came in they bag it, so do I ... but what is the time limit. I always said no more then a couple of days but that certainly is emperical and not based on any science at all. One reply came in explaining something about humidity needed to set of the chemical reaction and if bagging a partially used scrubber you have no humidity left to start propper chemical reaction .... no fuse so to speak .. or a very short one, depending on view point. That really got me thinking. Am I making a large and huge mistake bagging my partially used scrubber .... and even worse, by telling other people, students, and do it in front of them in plain sight, explaining that is ok to do, am I setting people up for suicide missions ?. That thought was and is sitting heavy on my shoulders. Maybe procedure should or need to be changed, or clearer stated, very clear, that it is not ok to re-use partially used scrubber material ... period. I do not know but what I know is thanx to your report is it made me even more thinking .... and it aint hurt, the thinking part I mean ... greetings Matt __________________ N 20' 37.617' W 87' 04.693' www.andreaswmatthes.com
(Offline)

30th October 2007, 02:00	#25 (permalink)
jdicediver Single/burdened with cash Current Rebreather/s: Megalodon Other Rebreather/s: Join Date: Jun 2006 Location: Calgary, Alberta Posts: 256	Re: Possible C02 Hit? Quote: (Originally Posted by mattmexico) yo Some weeks ago I was asking some questions here on Rebreather World on how people practice or care for their partially spend absorbent materials in regards to potential re-use. A lot replies came in they chuck it, period. A lot of replies came in they bag it, so do I ... but what is the time limit. I always said no more then a couple of days but that certainly is emperical and not based on any science at all. One reply came in explaining something about humidity needed to set of the chemical reaction and if bagging a partially used scrubber you have no humidity left to start propper chemical reaction .... no fuse so to speak .. or a very short one, depending on view point. That really got me thinking. Am I making a large and huge mistake bagging my partially used scrubber .... and even worse, by telling other people, students, and do it in front of them in plain sight, explaining that is ok to do, am I setting people up for suicide missions ?. That thought was and is sitting heavy on my shoulders. Maybe procedure should or need to be changed, or clearer stated, very clear, that it is not ok to re-use partially used scrubber material ... period. I do not know but what I know is thanx to your report is it made me even more thinking .... and it aint hurt, the thinking part I mean ... greetings Matt Matt, I agree with you 133%. I do feel that the best procedure is to toss a can full of partially used 'sorb if it isn't used within a short period. Anyone would agree that this would be the wisest choice. We all make decisions virtually daily that may indirectly affect the lives of others without having the slightest understanding of the amplitude or final impact of our statements having been heard. What is the reason some are elected within our political system and others are not? How people interpret our sometimes verbose yet seemingly convincing comments is far beyond our comprehension. Take the word religious for example, throw it out there, and you will receive at least ten differing definitions from one room containing only eight people. I have thought at times that an area that would be of benefit <although would take some time and work to develop and manage> and would prove to be functionally better than a "Search" function would be a FAQ section containing "Proven Majority Rules" If this idea is of slight interest, maybe a thread could be started regarding the possible development of same? Let's face it, I think it has been said before...We are the Policy Makers...Let us not be wrong. __________________ Regards; "Alterations performed under controlled conditions, on a closed course by a qualified Closed Circuit Diver" "Some people shouldn't dive...others shouldn't even get wet".
(Offline)

30th October 2007, 02:56	#26 (permalink)
Dave O Wreck Diver Current Rebreather/s: Sport Kiss Classic Kiss Other Rebreather/s: Sport Kiss Join Date: Aug 2007 Location: NJ Posts: 122	Re: Possible C02 Hit? Quote: (Originally Posted by mattmexico) yo Some weeks ago I was asking some questions here on Rebreather World on how people practice or care for their partially spend absorbent materials in regards to potential re-use. A lot replies came in they chuck it, period. A lot of replies came in they bag it, so do I ... but what is the time limit. I always said no more then a couple of days but that certainly is emperical and not based on any science at all. One reply came in explaining something about humidity needed to set of the chemical reaction and if bagging a partially used scrubber you have no humidity left to start propper chemical reaction .... no fuse so to speak .. or a very short one, depending on view point. That really got me thinking. Am I making a large and huge mistake bagging my partially used scrubber .... and even worse, by telling other people, students, and do it in front of them in plain sight, explaining that is ok to do, am I setting people up for suicide missions ?. That thought was and is sitting heavy on my shoulders. Maybe procedure should or need to be changed, or clearer stated, very clear, that it is not ok to re-use partially used scrubber material ... period. I do not know but what I know is thanx to your report is it made me even more thinking .... and it aint hurt, the thinking part I mean ... greetings Matt Matt, This comes to mind http://www.rebreatherworld.com/137949-post6.html __________________ Only people who bat for the wrong team wash their undersuits......... I wanna smell piss when I go diving, not ferkin' fabric softener! <decodiver> Schizophrenics never dive solo. My Blog
(Offline)

30th October 2007, 03:19	#27 (permalink)
jdicediver Single/burdened with cash Current Rebreather/s: Megalodon Other Rebreather/s: Join Date: Jun 2006 Location: Calgary, Alberta Posts: 256	Re: Possible C02 Hit? Quote: (Originally Posted by Dave O) Matt, This comes to mind http://www.rebreatherworld.com/137949-post6.html To Plagiarize the contents of the above post for sake of timing: Quote: (Originally Posted by Molecular Products Ltd) The reaction sequence shown in your note is an oversimplification of the actual chemical reaction sequence that occurs. Sodium carbonate is not formed at the pH of the reactions, it is sodium bicarbonate that acts as the carrier molecule. A better description is: Overall: CO2 + Ca(OH)2 => Ca(CO3) + H2O made up of the individual stages: CO2 + H2O <=> CO2 in solution (it just dissolves - it does not form carbonic acid) CO2 + NaOH => NaHCO2 NaHCO3 + Ca(OH)2 => Ca(CO3)2 + NaOH + H2O The NaOH in stage 3 is recycled to stage 2 and behaves as a catalyst. It should also be noted that there is a net gain in water. The overall reaction is not reversible under the conditions you describe and will not increase the capacity of the soda lime or allow it to be safely reused. Once soda lime has been left open or part used the water balance in the material is changed and the performance will be affected. Soda lime that is too dry or too wet will reduce the CO2 removal rate and place the diver at risk. It is not safe to keep part used soda lime for reuse for more than a few hours in your rebreather if it is to be again. This is because the water balance will start to redistribute and will adversely effect performance. The thinking on redistribution is also not useful as even if the unit did become homogenous, (which it won’t) the capacity would still be less than if the unit was used all at one time. This is because the reaction zone would be larger and the effective capacity of the remaining unreacted material will therefore be reduced. Hmmm...sobering information, from the manufacturer nonetheless. Pretty indisputable evidence I would have to say. I think this is the start of something good... __________________ Regards; "Alterations performed under controlled conditions, on a closed course by a qualified Closed Circuit Diver" "Some people shouldn't dive...others shouldn't even get wet".
(Offline)

30th October 2007, 12:43	#28 (permalink)
tibby untitled Current Rebreather/s: Megalodon Other Rebreather/s: Join Date: May 2007 Location: Salt Lake City, UT Posts: 337	Re: Possible C02 Hit? Quote: (Originally Posted by Dave O) Matt, This comes to mind http://www.rebreatherworld.com/137949-post6.html That's it, I'm chucking mine from now on unless I'll use it the same day. __________________ Does the voice of reason change when you add helium to the mix?...hmm
(Offline)

30th October 2007, 21:48	#29 (permalink)
Dsix36 Going Down? Current Rebreather/s: Optima Other Rebreather/s: Join Date: Aug 2007 Location: Deerfield Beach, Florida Posts: 976	Re: Possible C02 Hit? Quote: (Originally Posted by Dave O) Matt, This comes to mind http://www.rebreatherworld.com/137949-post6.html How does this apply to an ExtendAir cartridge? __________________ THE MORE THAT I LEARN, THE MORE THAT I STILL NEED TO LEARN!!!!!!
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31st October 2007, 05:53	#30 (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: 1,814	Re: Possible C02 Hit? Quote: (Originally Posted by mattmexico) One reply came in explaining something about humidity needed to set of the chemical reaction and if bagging a partially used scrubber you have no humidity left to start propper chemical reaction .... no fuse so to speak .. or a very short one, depending on view point. That really got me thinking. Am I making a large and huge mistake bagging my partially used scrubber .... and even worse, by telling other people, students, and do it in front of them in plain sight, explaining that is ok to do, am I setting people up for suicide missions ?. That thought was and is sitting heavy on my shoulders. Maybe procedure should or need to be changed, or clearer stated, very clear, that it is not ok to re-use partially used scrubber material ... period. I do not know but what I know is thanx to your report is it made me even more thinking .... and it aint hurt, the thinking part I mean ... greetings Matt Hi Matt, the point about humidity being needed for sorb to start working/fuse analogy is a good one and valid. But, I think that any time you store partially used sorb in a bag, it will have a lot more moisture in it that when it comes out of the tub due to the rection being started. So much so that when I take a canister out to store overnight, I let it dry out in the air for a while to prevent clumping before putting it in the bag, it's that wet. Now obviously 6 weeks is a long time and storing and/or using it in a cold place is not the same as bagging a scrubber for a few days in the tropics. But the principle is the same-everytime I have removed a scrubber it was much more moist than the stuff I filled it with out of the tub. If the ambient temp is high enough and the storage short enough, then reusing sorb shouldn't be a problem. But yes, it's still just a guess and who knows exactly where the line is, without some sort of expensive, time consuming tests? -Andy
(Offline)

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