Typical for Spherasorb behavior?

Stephane · 16th March 2007, 20:12

Hi Stuart,

Well, looks like a little bit of an ad for their products. Mine is better than yours.

Anyway, Mr Molecular Products, send me a sample of your sorb and I will test it against the Spharasorb I use.

***schford*** · 16th March 2007, 20:19

Quote: (Originally Posted by Stephane)

Hi Stuart,

Well, looks like a littlt bit of an ad for their products. Mine is better than yours.

Anyway, Mr Molecular Products, send me a sample of your sorb and I will test it against the Spharasorb I use.

Sounds fair to me - MP can you step up ?

Tom Rose · 16th March 2007, 20:29

Quote: (Originally Posted by schford)

Sounds fair to me - MP can you step up ?

What fun, Lets do this right....

Someone with some lab scales equest a pint or so of each scrubber material....Pour it into a container with a fixed volume using a few calibrated standard taps and weigh it.

But when you consider the results, some air space is needed for the gas to flow through.

I have used all of the scrubber material mentioned with no problem diving to 150 feet or less.

I was fascinated the first time I saw that the Dragersorb was shaped like little flying saucers or M&M candy. I remember that you can pack more of those into a space than spheres, but probably less than crushed material.

Interesting thread
Tom

fredrik · 17th March 2007, 11:41

Quote: (Originally Posted by fredrik)

Where did you find this information? Maby some other producer?

I didn´t read the user name before sending my post.
Now I have some questions:

Is "Molecular Products Ltd" a verified person?
Has Molecular given this "person" full authority to speak freely about their products? Can we trust this information?
Is it OK for a producer to talk like this about a competitors products?

I´ve also been told that if you would like to write, or answer qustions about your own products on Rebreather World you have to be a sponsor.

amaiel · 17th March 2007, 15:46

Quote: (Originally Posted by Molecular Products Ltd)

......

........ ....... Also, spheres have a greater distance to the centre of the particle than our 'D' shaped particles, leading to a higher amount of unused/unusable material at the centre. Both of these effects lead to less capacity per unit volume AND per unit weight.

Regards

That sounds strange to me........

The Final Report On Two Brand Name Soda Limes Comparative Testing
SPHERASORB (Intersurgical, Great Britain) And SOFNOLIME (Molecular Products,
Great Britain).
The research was made in the Moscow Vishnevski Surgery Institute anaesthetic department
(Russian Academy of Medical Science) on behalf of Moscow ScientificAnaesthetic Society.

The aim of study —

to determine actual functioning duration of two Soda Limes. The dutation was

determined from the moment of Soda Lime 1kg filling up the absorber till 0,2% EtC02 recording on a capnograf.

The inactivity time (periods between operations, week-ends) was set aside.
Testing conditions — the experiment was made with 1 kg of Soda Lime with a fresh gas flow rate equal to
1 L/min in the patient circuit. The number of tests with each type of Soda Lime — 6 (six). The total tests number
— 12 (twelve). The complete list of experiment conditions is indicated in Appendix 1. The study was held with
the patients that had operations on account of blood vessels and abdomen internal. Groups in Appendix 2
indicate the demographic data.
Duration (min) -. /./0123 4Number of test .5670185 0,2% EtC02
Spherasorb

Sofnolime

Test :1 22 hours 17 min = 1337 min. 16 hours 25 min = 985 min

Test :2 20 hours == 1200 min 13 hours 45 min == 825 min
Test :3 23 hours 30 min =1410 min 14 hours 40 min = 880 min
Test :4 19 hours 05 min =1145 min 12 hours 38 min = 758 min
Test :5 16 hours 40 min =1000 min 10 hours 30 min = 630 min
Test :6 18 hours 35 min =1115 min 15 hours 55 min = 955 min
Average duration min. (1 +/- m ) 1201,17 +/- 114,89min 838,83±101,17 min
Duration difference (hours, minutes) 362,33 =>?.= 6 hours 04 minutes
Duration difference (%) 30,17 %
Conclusion: The Spherasorb 1 kg duration exceeds the Sofnolime 1 kg duration by 30,17%
on average.
Additional experimental observation: The lawer dust content level has been noticed in Spherasorb in comparison with Sofnolime,
which is important for the reduction of dust ingress into patient lungs as well as for the extension of anaesthetic machines exploitation

(with respect to irreversible valves, etc).

_________________________________________________

DURATION OF SPHERASORB VS COMPETITOR IN
THE CATO AND CICERO 1.5 KG ABSORBER:
UNIVERSITY OF DUSSELDORF JANUARY TO APRIL 1998
This report has been compiled based on figures and test information supplied by
The Anaesthetic Department at the University of Dusseldorf.
1. Test protocol:
1.1. Anaesthetic machines used: Cato and Cicero. These are Draeger machines
with the same absorber and circuitry. The difference between this machine is
software and monitoring only.
1.2. Fresh gas flows used: 0.3 to 1.4 L/min.
1.3. Type of operation: Neurosurgery.
1.4. Only actual usage time recorded.
1.5. Definition of exhaustion: 2 % Inspired Carbon Dioxide.

2. Results:

Spherasorb Sodasorb

Hours of use Hours of use

38.15 31.40
37.30 30.50
42.40 32.35
39.10 29.50
41.25 30.30
36.45 31.20
43.20 32.10
40.45 28.25
38.50 29.30
42.10 19.45
39.30 31.40
40.45 29.50
37.30 31.10
41.10 27.50
40.45 28.30
42.30 30.55
39.35 29.25
44.25 30.35
40.20 31.40

Each figure represents the accumulative usage time for one absorber fill.

_________________________________________________

Dutchy · 17th March 2007, 18:10

Quote: (Originally Posted by Molecular Products Ltd)

Spherasorb has not been passed for use in diving.

What's so different from the medical application? Well the flow is bigger. Being able to handle the bigger flow is not an achievement of the sorb. The design of the scrubber is different. More sorb and a longer path for the gas are just two factors that help increase the efficiency of a scrubber. The sorb is just one of the other factors. It is not that hard to think of a scrubber that kills you with small grain sofnolime that would work fine with with spherasorb AND the other way around. The key question is what is your scrubber designed for and is this design tolerant enough to take another sorb with different size/shape/recipe (conversion rate influencing factors) for the specific dive that you are going to make. (depth, gas mixture and mostly temperature being the key factors here)

The blanket statement here is utterly useless in this respect and may suggest something too much imho.

The technical explanation is utterly BS from the same point of view. The claimed closer packing may increase the work of breathing by too much. (but could be fine with more He)... The bottom line here would be that I think that claims like these shouldn't have a place here when brought to us as mere blanket statements unless there's a test that proves that it has lower WOB and longer duration and more absorbing capacity (both absolute and in absorbing speed) all at the same time

.

Which brings me to the counter evidence. Just as useless? With our flows being tenfold (or more!) higher it isn't just the absolute capacity that counts. Apart from being able to chemically bind a lot of CO2 (proven) it also needs to do that at a much higher (as much as 2liter/minute) rate.

Let's do Tom's experiment for both a (simulated?) deep dive and for a shallowdive and see what's sufficient and what's best...

Gilles · 18th March 2007, 07:36

I just came home after a 2 hr splash in 20-25m (edit: actually mostly 10-15m), swimming with a whale shark during the last 30 minutes or so. WOW!

My standard axial canister was on hour 7 & 8 using sherasorb. I flushed and semi-closed the last 10 minutes or so. Was feeling a bit off chasing after the shark. Could've been my imagination as I knew I was pushing the sorb.

The South China Sea is some 26 degC now and loop is about 32 degC.

I've only used Sofno once, and was pleased with it. The Divesorb (Drager) I've used has been very dusty, and significantly harder to breathe. I've gone through some 40 Kg of Sphera, and I have no issues with the stuff whatsoever.

***schford*** · 18th March 2007, 07:59

Quote: (Originally Posted by Gilles)

My standard axial canister was on hour 7 & 8 using sherasorb. I flushed and semi-closed the last 10 minutes or so. Was feeling a bit off chasing after the shark. Could've been my imagination as I knew I was pushing the sorb.
.

Please don't push your Sorb I know people who have died as they did this. 8 Hours ons a standard axial is WAY WAY more than I would dream of pushing it.

Stuart

decoweenie · 18th March 2007, 08:36

Quote: (Originally Posted by Gilles)

My standard axial canister was on hour 7 & 8 using sherasorb...

I know your local water is warm like here, but 8 hours is really pushing it especially if the previous hours involved hard work, or it just happens that you have to work hard on your 7th or 8th hour.

I am guiltly for pushing the CK scrubber in the first few years as well (i.e. curious about the limit) so can't speak too loud, but be careful and should be prepared to go off the loop as effectively as possible - if you need to.

16th March 2007, 20:12	#11 (permalink)
Stephane Hey! Ho! Let's go! Current Rebreather/s: rEvo Other Rebreather/s: rEvo Join Date: Nov 2005 Location: Nantes - France Posts: 735	Re: Typical for Spherasorb behavior? Hi Stuart, Well, looks like a little bit of an ad for their products. Mine is better than yours. Anyway, Mr Molecular Products, send me a sample of your sorb and I will test it against the Spharasorb I use. __________________ Stéphane Hammer-rEvo powered! Last edited by Stephane : 16th March 2007 at 20:22.
(Offline)

16th March 2007, 20:19	#12 (permalink)
*schford* Despotic Overlord Current Rebreather/s: Megalodon Sport Kiss Other Rebreather/s: Join Date: Jan 2005 Location: London, UK Posts: 3,671	Re: Typical for Spherasorb behavior? Quote: (Originally Posted by Stephane) Hi Stuart, Well, looks like a littlt bit of an ad for their products. Mine is better than yours. Anyway, Mr Molecular Products, send me a sample of your sorb and I will test it against the Spharasorb I use. Sounds fair to me - MP can you step up ? __________________ Bailout and Kit Management account for Murphy's Law The only bad question is one you did not ask and later wish you had. Use of Rebreather World is subject to the Rebreather World Terms & Conditions of Use
(Offline)

16th March 2007, 20:29	#13 (permalink)
Tom Rose Still Learning Current Rebreather/s: Other CCR Home Build Other Rebreather/s: Prism Topaz Other CCR Home Build Join Date: Oct 2005 Location: USA,North Carolina Posts: 330	Re: Typical for Spherasorb behavior? Quote: (Originally Posted by schford) Sounds fair to me - MP can you step up ? What fun, Lets do this right.... Someone with some lab scales equest a pint or so of each scrubber material....Pour it into a container with a fixed volume using a few calibrated standard taps and weigh it. But when you consider the results, some air space is needed for the gas to flow through. I have used all of the scrubber material mentioned with no problem diving to 150 feet or less. I was fascinated the first time I saw that the Dragersorb was shaped like little flying saucers or M&M candy. I remember that you can pack more of those into a space than spheres, but probably less than crushed material. Interesting thread Tom __________________ The 50-50-90 rule: Anytime I have a 50-50 chance of getting something right, there's a 90% probability I'll get it wrong the first time. www.atlimp.com
(Offline)

17th March 2007, 11:41	#14 (permalink)
fredrik Rekodeko. Sweden Current Rebreather/s: Classic Kiss Other CCR Other Rebreather/s: Other CCR Join Date: Apr 2005 Location: Sweden Posts: 191	Re: Typical for Spherasorb behavior? Quote: (Originally Posted by fredrik) Where did you find this information? Maby some other producer? I didn´t read the user name before sending my post. Now I have some questions: Is "Molecular Products Ltd" a verified person? Has Molecular given this "person" full authority to speak freely about their products? Can we trust this information? Is it OK for a producer to talk like this about a competitors products? I´ve also been told that if you would like to write, or answer qustions about your own products on Rebreather World you have to be a sponsor. __________________ Fredrik Rekodeko, Sweden http://www.rekodeko.se
(Offline)

17th March 2007, 15:46	#15 (permalink)
amaiel New Member Current Rebreather/s: Other SCR Other Rebreather/s: Other SCR Join Date: Dec 2005 Location: Milan Posts: 13	Re: Typical for Spherasorb behavior? Quote: (Originally Posted by Molecular Products Ltd) ...... ........ ....... Also, spheres have a greater distance to the centre of the particle than our 'D' shaped particles, leading to a higher amount of unused/unusable material at the centre. Both of these effects lead to less capacity per unit volume AND per unit weight. Regards That sounds strange to me........ The Final Report On Two Brand Name Soda Limes Comparative Testing SPHERASORB (Intersurgical, Great Britain) And SOFNOLIME (Molecular Products, Great Britain). The research was made in the Moscow Vishnevski Surgery Institute anaesthetic department (Russian Academy of Medical Science) on behalf of Moscow ScientificAnaesthetic Society. The aim of study — to determine actual functioning duration of two Soda Limes. The dutation was determined from the moment of Soda Lime 1kg filling up the absorber till 0,2% EtC02 recording on a capnograf. The inactivity time (periods between operations, week-ends) was set aside. Testing conditions — the experiment was made with 1 kg of Soda Lime with a fresh gas flow rate equal to 1 L/min in the patient circuit. The number of tests with each type of Soda Lime — 6 (six). The total tests number — 12 (twelve). The complete list of experiment conditions is indicated in Appendix 1. The study was held with the patients that had operations on account of blood vessels and abdomen internal. Groups in Appendix 2 indicate the demographic data. Duration (min) -. /./0123 4Number of test .5670185 0,2% EtC02 Spherasorb Sofnolime Test :1 22 hours 17 min = 1337 min. 16 hours 25 min = 985 min Test :2 20 hours == 1200 min 13 hours 45 min == 825 min Test :3 23 hours 30 min =1410 min 14 hours 40 min = 880 min Test :4 19 hours 05 min =1145 min 12 hours 38 min = 758 min Test :5 16 hours 40 min =1000 min 10 hours 30 min = 630 min Test :6 18 hours 35 min =1115 min 15 hours 55 min = 955 min Average duration min. (1 +/- m ) 1201,17 +/- 114,89min 838,83±101,17 min Duration difference (hours, minutes) 362,33 =>?.= 6 hours 04 minutes Duration difference (%) 30,17 % Conclusion: The Spherasorb 1 kg duration exceeds the Sofnolime 1 kg duration by 30,17% on average. Additional experimental observation: The lawer dust content level has been noticed in Spherasorb in comparison with Sofnolime, which is important for the reduction of dust ingress into patient lungs as well as for the extension of anaesthetic machines exploitation (with respect to irreversible valves, etc). _________________________________________________ DURATION OF SPHERASORB VS COMPETITOR IN THE CATO AND CICERO 1.5 KG ABSORBER: UNIVERSITY OF DUSSELDORF JANUARY TO APRIL 1998 This report has been compiled based on figures and test information supplied by The Anaesthetic Department at the University of Dusseldorf. 1. Test protocol: 1.1. Anaesthetic machines used: Cato and Cicero. These are Draeger machines with the same absorber and circuitry. The difference between this machine is software and monitoring only. 1.2. Fresh gas flows used: 0.3 to 1.4 L/min. 1.3. Type of operation: Neurosurgery. 1.4. Only actual usage time recorded. 1.5. Definition of exhaustion: 2 % Inspired Carbon Dioxide. 2. Results: Spherasorb Sodasorb Hours of use Hours of use 38.15 31.40 37.30 30.50 42.40 32.35 39.10 29.50 41.25 30.30 36.45 31.20 43.20 32.10 40.45 28.25 38.50 29.30 42.10 19.45 39.30 31.40 40.45 29.50 37.30 31.10 41.10 27.50 40.45 28.30 42.30 30.55 39.35 29.25 44.25 30.35 40.20 31.40 Each figure represents the accumulative usage time for one absorber fill. _________________________________________________
(Offline)

17th March 2007, 18:10	#16 (permalink)
Dutchy SK#007 Current Rebreather/s: Sport Kiss Other Rebreather/s: Join Date: Apr 2006 Location: Nieuwegein (The Netherlands) Posts: 724	Re: Typical for Spherasorb behavior? Quote: (Originally Posted by Molecular Products Ltd) Spherasorb has not been passed for use in diving. What's so different from the medical application? Well the flow is bigger. Being able to handle the bigger flow is not an achievement of the sorb. The design of the scrubber is different. More sorb and a longer path for the gas are just two factors that help increase the efficiency of a scrubber. The sorb is just one of the other factors. It is not that hard to think of a scrubber that kills you with small grain sofnolime that would work fine with with spherasorb AND the other way around. The key question is what is your scrubber designed for and is this design tolerant enough to take another sorb with different size/shape/recipe (conversion rate influencing factors) for the specific dive that you are going to make. (depth, gas mixture and mostly temperature being the key factors here) The blanket statement here is utterly useless in this respect and may suggest something too much imho. The technical explanation is utterly BS from the same point of view. The claimed closer packing may increase the work of breathing by too much. (but could be fine with more He)... The bottom line here would be that I think that claims like these shouldn't have a place here when brought to us as mere blanket statements unless there's a test that proves that it has lower WOB and longer duration and more absorbing capacity (both absolute and in absorbing speed) all at the same time . Which brings me to the counter evidence. Just as useless? With our flows being tenfold (or more!) higher it isn't just the absolute capacity that counts. Apart from being able to chemically bind a lot of CO2 (proven) it also needs to do that at a much higher (as much as 2liter/minute) rate. Let's do Tom's experiment for both a (simulated?) deep dive and for a shallowdive and see what's sufficient and what's best... __________________ = This post is environmentally friendly. It is composed of 100% recycled electrons only. = SK #007
(Offline)

18th March 2007, 07:36	#17 (permalink)
Gilles Worship the feminine Current Rebreather/s: Megalodon Other Rebreather/s: Join Date: Sep 2005 Location: Den Haag (Netherlands) Posts: 762	Re: Typical for Spherasorb behavior? I just came home after a 2 hr splash in 20-25m (edit: actually mostly 10-15m), swimming with a whale shark during the last 30 minutes or so. WOW! My standard axial canister was on hour 7 & 8 using sherasorb. I flushed and semi-closed the last 10 minutes or so. Was feeling a bit off chasing after the shark. Could've been my imagination as I knew I was pushing the sorb. The South China Sea is some 26 degC now and loop is about 32 degC. I've only used Sofno once, and was pleased with it. The Divesorb (Drager) I've used has been very dusty, and significantly harder to breathe. I've gone through some 40 Kg of Sphera, and I have no issues with the stuff whatsoever. __________________ Gilles http://www.dirrebreather.com Last edited by Gilles : 18th March 2007 at 07:46.
(Offline)

18th March 2007, 07:59	#18 (permalink)
*schford* Despotic Overlord Current Rebreather/s: Megalodon Sport Kiss Other Rebreather/s: Join Date: Jan 2005 Location: London, UK Posts: 3,671	Re: Typical for Spherasorb behavior? Quote: (Originally Posted by Gilles) My standard axial canister was on hour 7 & 8 using sherasorb. I flushed and semi-closed the last 10 minutes or so. Was feeling a bit off chasing after the shark. Could've been my imagination as I knew I was pushing the sorb. . Please don't push your Sorb I know people who have died as they did this. 8 Hours ons a standard axial is WAY WAY more than I would dream of pushing it. Stuart __________________ Bailout and Kit Management account for Murphy's Law The only bad question is one you did not ask and later wish you had. Use of Rebreather World is subject to the Rebreather World Terms & Conditions of Use
(Offline)

18th March 2007, 08:36	#19 (permalink)
decoweenie Crash Test Dummy Current Rebreather/s: Other CCR Other Rebreather/s: Other CCR Join Date: Feb 2005 Location: Cairo Posts: 5,510	Re: Typical for Spherasorb behavior? Quote: (Originally Posted by Gilles) My standard axial canister was on hour 7 & 8 using sherasorb... I know your local water is warm like here, but 8 hours is really pushing it especially if the previous hours involved hard work, or it just happens that you have to work hard on your 7th or 8th hour. I am guiltly for pushing the CK scrubber in the first few years as well (i.e. curious about the limit) so can't speak too loud, but be careful and should be prepared to go off the loop as effectively as possible - if you need to. __________________ "...after a while you get bored offering advice to a bull that like to keep butting the fence with its head rather than walking through the open gate..." - Rebreather World PM
(Offline)

Thread Tools
Show Printable Version Email this Page
Display Modes
Linear Mode Switch to Hybrid Mode Switch to Threaded Mode