Scrubber Duration

Pierre Farrugia · 26th June 2005, 21:53

Hello all,

We are all teached about scrubber duration and that you cannot use it twice for a deep dive.

1. Only use Sofnolime 797
2. Maximum scrubber time 180 minutes

3. Be shallower than 50m at all times after 100 minutes use

4. Be shallower than 20m at all times after 140 minutes use

5. If in doubt, tip it out

6. Always re-grease and check the fitting of the scrubber O ring and spacer

So how do people use it from 120m dives with a 30 min bottom time ? Are we being too conservative about it's duration? (I am not implying to use it longer just plain curiosity) or there is something I am not understanding ?

What you think ?

NB: please don't tell me that it's too deep for me, I know but I am curious so 40m for me till now

***Decodiver*** · 26th June 2005, 22:34

Quote: (Originally Posted by Pierre Farrugia)

So how do people use it from 120m dives with a 30 min bottom time ? Are we being too conservative about it's duration? (I am not implying to use it longer just plain curiosity) or there is something I am not understanding ?

Well my Maltese friend,

If you do 125m for 30 mins you will still be shallower than 50m after 100 minutes run time. In fact you arrive at 24m at 104 minutes.

You will also be shallower than 20m after 140 minutes, using a dil of 6/72 with a setpoint of 1.2 PPO2 changing to 20/30 @ 1.4 PPO2. There you arrive at 15 metres at 129 minutes.

So this keeps you within the manufacturers' guidelines however you will blow the total runtime, my tables give me an RT of 353 minutes (5 hours 53 minutes) for that dive. Easily achievable on the Inspiration.

Disclaimer: These are my thoughts and not those of any particular agency. Do not copy these profiles as you may cause yourself/others serious injuries or die.

Cheers,

Dave Cooper.

***caveseeker7*** · 26th June 2005, 23:45

Nice disclaimer, Dave.

Considering the 5 hrs 53 mins runtime in your example I would like to add two points:
1. It may well be achievable, but is by no means guaranteed
2. 30 min bottomtime and several hrs deco is not the same as swimming around for 5 hrs 53 mins.

RebreatherDave · 27th June 2005, 07:28

Rumor has it the guys are getting 7 hour scrubber run times in their YBOD's when running Vision scrubbers with the axial thermistors....

Pierre Farrugia · 27th June 2005, 08:09

Thanks Dave,

Can I say you gave me a Mega Answer

an other question you said that you change from 1.2 set point to 1.4, I assume you do this manual right ?

Quote: (Originally Posted by Decodiver)

Well my Maltese friend,

If you do 125m for 30 mins you will still be shallower than 50m after 100 minutes run time. In fact you arrive at 24m at 104 minutes.

You will also be shallower than 20m after 140 minutes, using a dil of 6/72 with a setpoint of 1.2 PPO2 changing to 20/30 @ 1.4 PPO2. There you arrive at 15 metres at 129 minutes.

So this keeps you within the manufacturers' guidelines however you will blow the total runtime, my tables give me an RT of 353 minutes (5 hours 53 minutes) for that dive. Easily achievable on the Inspiration.

Disclaimer: These are my thoughts and not those of any particular agency. Do not copy these profiles as you may cause yourself/others serious injuries or die.

Cheers,

Dave Cooper.

jhaaja · 27th June 2005, 08:28

Why should it be done manually? Just go to menu mode and set high setpoint to 1,4 and let the solenoid work instead of your finger

JH
Finland

Pierre Farrugia · 27th June 2005, 08:36

Just in case,better I take my card out first

,

So can you change the set point underwater on a YBOD ? As I am no sure, is it same as onland, switch to 0.7 and the acess the menu ?

Pierre

Quote: (Originally Posted by jhaaja)

Why should it be done manually? Just go to menu mode and set high setpoint to 1,4 and let the solenoid work instead of your finger

JH
Finland

jhaaja · 27th June 2005, 09:01

Quote: (Originally Posted by Pierre Farrugia)

Just in case,better I take my card out first

,

So can you change the set point underwater on a YBOD ? As I am no sure, is it same as onland, switch to 0.7 and the acess the menu ?

Pierre

Yep, switch to low setpoint by pushing the middle slider towards the display for 2s and then just enter menu mode by pushing the left side and right side sliders towards the display inside 0,5s.

In menu mode you can then change the setpoints, brightness and reset the on-time clock.

The oxygen controller is not operating while you are in menu mode. You will leave menu mode by just going through all the steps or just leaving it alone for 15s. After 15s it will return to dive mode to low setpoint.

JH
"Also a Newbie YBOD pilot"
Finland

Pierre Farrugia · 28th June 2005, 16:27

Dave,

I know that dives like these are nearly experimental but staying 30min with a flow of 13.5bar, you should be using the upper part of scrubber, wright ? Could be a dive like this make you use scrubber more efficiently due to using different fronts or I understood everything wrongly? Do people use their scrubber for 2 deep dives, eg in the 60m range?

Quote: (Originally Posted by Decodiver)

Well my Maltese friend,

If you do 125m for 30 mins you will still be shallower than 50m after 100 minutes run time. In fact you arrive at 24m at 104 minutes.

You will also be shallower than 20m after 140 minutes, using a dil of 6/72 with a setpoint of 1.2 PPO2 changing to 20/30 @ 1.4 PPO2. There you arrive at 15 metres at 129 minutes.

So this keeps you within the manufacturers' guidelines however you will blow the total runtime, my tables give me an RT of 353 minutes (5 hours 53 minutes) for that dive. Easily achievable on the Inspiration.

Disclaimer: These are my thoughts and not those of any particular agency. Do not copy these profiles as you may cause yourself/others serious injuries or die.

Cheers,

Dave Cooper.

jhaaja · 29th June 2005, 05:59

Quote: (Originally Posted by Pierre Farrugia)

Can I say that this is

and this thread has gone tits up

so hopfully this will get us back on track on a very serious question!

It was Stuart´s fault he made us change the Avatars

In YBOD tha CO2 rich gas comes to the scrubber from the bottom. When you inhale you drag the gas through the scrubber media from bottom up. That is why on a new scrubber media the reaction starts from the bottom. When the dive proceeds the reaction area moves higher in the scrubber media.

JH
Finland

26th June 2005, 21:53	#1 (permalink)
Pierre Farrugia Custom Title Allowed! Current Rebreather/s: Inspiration Classic Other Rebreather/s: Join Date: Feb 2005 Location: Malta Posts: 636	Scrubber Duration Hello all, We are all teached about scrubber duration and that you cannot use it twice for a deep dive. 1. Only use Sofnolime 797 2. Maximum scrubber time 180 minutes 3. Be shallower than 50m at all times after 100 minutes use 4. Be shallower than 20m at all times after 140 minutes use 5. If in doubt, tip it out 6. Always re-grease and check the fitting of the scrubber O ring and spacer So how do people use it from 120m dives with a 30 min bottom time ? Are we being too conservative about it's duration? (I am not implying to use it longer just plain curiosity) or there is something I am not understanding ? What you think ? NB: please don't tell me that it's too deep for me, I know but I am curious so 40m for me till now __________________ Pierre Farrugia My wife told me " If you don't quit diving I'm going to leave you" My reply " God, I'll miss you" www.atlam.org www.divemed.com
(Offline)

26th June 2005, 22:34	#2 (permalink)
*Decodiver* Administrator Current Rebreather/s: Other CCR Other Rebreather/s: Other CCR Join Date: Jan 2005 Location: Geneva Posts: 2,190	Quote: (Originally Posted by Pierre Farrugia) So how do people use it from 120m dives with a 30 min bottom time ? Are we being too conservative about it's duration? (I am not implying to use it longer just plain curiosity) or there is something I am not understanding ? Well my Maltese friend, If you do 125m for 30 mins you will still be shallower than 50m after 100 minutes run time. In fact you arrive at 24m at 104 minutes. You will also be shallower than 20m after 140 minutes, using a dil of 6/72 with a setpoint of 1.2 PPO2 changing to 20/30 @ 1.4 PPO2. There you arrive at 15 metres at 129 minutes. So this keeps you within the manufacturers' guidelines however you will blow the total runtime, my tables give me an RT of 353 minutes (5 hours 53 minutes) for that dive. Easily achievable on the Inspiration. Disclaimer: These are my thoughts and not those of any particular agency. Do not copy these profiles as you may cause yourself/others serious injuries or die. Cheers, Dave Cooper. __________________ CCR/OC Trimix Instructor Trainer CCR Training to Mixed Gas in Switzerland, France, UK & Germany on Megalodon/COPIS-Megalodon/KISS/Sport KISS/Ouroboros/rEvo/Inspiration/Evolution/Sentinel www.zerogravitydiving.com Rebreather World Terms & Conditions
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26th June 2005, 23:45	#3 (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: 5,535	Nice disclaimer, Dave. Considering the 5 hrs 53 mins runtime in your example I would like to add two points: 1. It may well be achievable, but is by no means guaranteed 2. 30 min bottomtime and several hrs deco is not the same as swimming around for 5 hrs 53 mins. __________________ 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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27th June 2005, 07:28	#4 (permalink)
RebreatherDave Maximum **** Current Rebreather/s: Inspiration Classic Other Rebreather/s:** Join Date: May 2005 Location: L.A., where the debris meets the sea Posts: 226	Rumor has it the guys are getting 7 hour scrubber run times in their YBOD's when running Vision scrubbers with the axial thermistors....
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27th June 2005, 08:09	#5 (permalink)
Pierre Farrugia Custom Title Allowed! Current Rebreather/s: Inspiration Classic Other Rebreather/s: Join Date: Feb 2005 Location: Malta Posts: 636	Thanks Dave, Can I say you gave me a Mega Answer an other question you said that you change from 1.2 set point to 1.4, I assume you do this manual right ? Quote: (Originally Posted by Decodiver) Well my Maltese friend, If you do 125m for 30 mins you will still be shallower than 50m after 100 minutes run time. In fact you arrive at 24m at 104 minutes. You will also be shallower than 20m after 140 minutes, using a dil of 6/72 with a setpoint of 1.2 PPO2 changing to 20/30 @ 1.4 PPO2. There you arrive at 15 metres at 129 minutes. So this keeps you within the manufacturers' guidelines however you will blow the total runtime, my tables give me an RT of 353 minutes (5 hours 53 minutes) for that dive. Easily achievable on the Inspiration. Disclaimer: These are my thoughts and not those of any particular agency. Do not copy these profiles as you may cause yourself/others serious injuries or die. Cheers, Dave Cooper. __________________ Pierre Farrugia My wife told me " If you don't quit diving I'm going to leave you" My reply " God, I'll miss you" www.atlam.org www.divemed.com
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27th June 2005, 08:28	#6 (permalink)
jhaaja Custom Title Allowed! Current Rebreather/s: Inspiration Classic Other Rebreather/s: Join Date: Mar 2005 Location: Finland Posts: 885	Why should it be done manually? Just go to menu mode and set high setpoint to 1,4 and let the solenoid work instead of your finger JH Finland
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27th June 2005, 08:36	#7 (permalink)
Pierre Farrugia Custom Title Allowed! Current Rebreather/s: Inspiration Classic Other Rebreather/s: Join Date: Feb 2005 Location: Malta Posts: 636	Just in case,better I take my card out first , So can you change the set point underwater on a YBOD ? As I am no sure, is it same as onland, switch to 0.7 and the acess the menu ? Pierre Quote: (Originally Posted by jhaaja) Why should it be done manually? Just go to menu mode and set high setpoint to 1,4 and let the solenoid work instead of your finger JH Finland __________________ Pierre Farrugia My wife told me " If you don't quit diving I'm going to leave you" My reply " God, I'll miss you" www.atlam.org www.divemed.com
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27th June 2005, 09:01	#8 (permalink)
jhaaja Custom Title Allowed! Current Rebreather/s: Inspiration Classic Other Rebreather/s: Join Date: Mar 2005 Location: Finland Posts: 885	Quote: (Originally Posted by Pierre Farrugia) Just in case,better I take my card out first , So can you change the set point underwater on a YBOD ? As I am no sure, is it same as onland, switch to 0.7 and the acess the menu ? Pierre Yep, switch to low setpoint by pushing the middle slider towards the display for 2s and then just enter menu mode by pushing the left side and right side sliders towards the display inside 0,5s. In menu mode you can then change the setpoints, brightness and reset the on-time clock. The oxygen controller is not operating while you are in menu mode. You will leave menu mode by just going through all the steps or just leaving it alone for 15s. After 15s it will return to dive mode to low setpoint. JH "Also a Newbie YBOD pilot" Finland
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28th June 2005, 16:27	#9 (permalink)
Pierre Farrugia Custom Title Allowed! Current Rebreather/s: Inspiration Classic Other Rebreather/s: Join Date: Feb 2005 Location: Malta Posts: 636	Dave, I know that dives like these are nearly experimental but staying 30min with a flow of 13.5bar, you should be using the upper part of scrubber, wright ? Could be a dive like this make you use scrubber more efficiently due to using different fronts or I understood everything wrongly? Do people use their scrubber for 2 deep dives, eg in the 60m range? Quote: (Originally Posted by Decodiver) Well my Maltese friend, If you do 125m for 30 mins you will still be shallower than 50m after 100 minutes run time. In fact you arrive at 24m at 104 minutes. You will also be shallower than 20m after 140 minutes, using a dil of 6/72 with a setpoint of 1.2 PPO2 changing to 20/30 @ 1.4 PPO2. There you arrive at 15 metres at 129 minutes. So this keeps you within the manufacturers' guidelines however you will blow the total runtime, my tables give me an RT of 353 minutes (5 hours 53 minutes) for that dive. Easily achievable on the Inspiration. Disclaimer: These are my thoughts and not those of any particular agency. Do not copy these profiles as you may cause yourself/others serious injuries or die. Cheers, Dave Cooper. __________________ Pierre Farrugia My wife told me " If you don't quit diving I'm going to leave you" My reply " God, I'll miss you" www.atlam.org www.divemed.com
(Offline)

29th June 2005, 05:59	#10 (permalink)
jhaaja Custom Title Allowed! Current Rebreather/s: Inspiration Classic Other Rebreather/s: Join Date: Mar 2005 Location: Finland Posts: 885	Quote: (Originally Posted by Pierre Farrugia) Can I say that this is and this thread has gone tits up so hopfully this will get us back on track on a very serious question! It was Stuart´s fault he made us change the Avatars In YBOD tha CO2 rich gas comes to the scrubber from the bottom. When you inhale you drag the gas through the scrubber media from bottom up. That is why on a new scrubber media the reaction starts from the bottom. When the dive proceeds the reaction area moves higher in the scrubber media. JH Finland
(Offline)

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