Extend Air For Dolphin rebreather

[Life-Is-Good-Diver]

Im just wondering as if anyone has any experiance with the ExtendAir CO2 absorbent retrofit and the Extend-Air CO2 absorbent canisters . I was thinking as i am the high bidder on ebay right now for the retro fit kit for the Dolphin, if anyone has any pro's and con's they would like to share or any experiance's using it. I used it on my training , both with the kit,and using the granular's , but two thing's come to mind, one is that the website that offer's it say's it last two-three times longer then the
granular's , and elimating Caustic cocktails.

Does that mean i would dive the whole weekend, and put 6+ hour's on one CO2 absorbent canister and never change it? Also they say to go by the manafactour's recomendation's as far as scrubber life, etc, on the Dolphin they recommend 3+ hour's, i have to look at the manual again, but does that mean these
CO2 absorbent canisters are used for 6+ hour's if they last 2-3 times longer?

There $120 for 4 CO2 absorbent canisters , if i can get say 4 seperate weekends of diving out of a case, for that amount, then may be worth it, but if im changing them out as regular as the granular's, that could get quit costley.

Thank's for helping a newbie out

 

[caveseeker7]

... any experiance with the ExtendAir CO2 absorbent retrofit and the Extend-Air CO2 absorbent canisters

My experience with them is minimal, I tried an ExtenAir equiped Dolphin in the pool once to see how it breathes. My 20odd hours on the Atlantis when it first came out are so long ago I couldn't really compare, but it seemed decent for the rebreather it is.

any pro's and con's ...

Pros: Handling, of course, is brilliantly simple. Chances of channeling much reduced (unless seals are defect), chances of caustic cocktail much reduced since there is pretty much no dust.

Cons: Price, the cartridges started out at $66/box of 4 in 2002, were $78/box last year and are now $120/box. So much for becoming less expensive due to availability for more RBs (first Dolphin, then Azi, now Inspiration ... makes me wonder how they'll charge once the DiveRite hits the market). Not as easy to transport as sorb. Not as easily disposed of as sorb, the plastic cartridge remains and afaik is can't be receycled. They are also harder to find than granular sorb. And finally, testing and rating leaves much to be desired. For a while the verbally stated their cartridges are good for 4 hours, but were willing to only put half of that, 2 hours in writing.

... website that offer's it say's it last two-three times longer then the
granular's ...

At DEMA I visited the Micropore booth , where they had info sheets available. According to the graph, the CO2 concentration in the loop reaches 0.5% at about 210 minutes. Testing was performed at 40 RMV, 1.35 LPM CO2 injection, 1 ata and 13 degrees C/55.4 degrees F. That's somewhay of an issue for me, as (a) it doesn't match CE or NAVY protocol and (b) duration is depth depended, so 1 ata is utterly insufficent and useless for anyone diving deeper than his bath tub.

Does that mean i would dive the whole weekend, and put 6+ hour's on one CO2 absorbent canister and never change it?

I rather doubt that, not even in FL. I certainly wouldn't push that bucket that far.

Also they say to go by the manafactour's recomendation's as far as scrubber life, etc, on the Dolphin they recommend 3+ hour's

Dräger/Aqualung's rating for the Dolphin using DiveSorb are available for download in their tech library . They seem a whole lot more reasonable than Micropore's.

Simply put, if you're able and willing to pay considerably more for the advantages listed above, and have the stock scrubber for travel, it may be worth it for you. But I'd be carefull pushing the scrubber past the 210 minute rating. What you may add in duration due to lower CO2 production you may well loose due to depth. And when the scrubber is exhausted, CO2 levels rise fast. Curves get pretty steep, I've seen them for the Prism and SM1600 scrubbers, and I have the one for the cartridge. Absorbant is cheap in comparison for the price you may pay for a CO2 hit.

 

[BigJetDriver]

According to the graph, the CO2 concentration in the loop reaches 0.5% at about 210 minutes. Testing was performed at 40 RMV, 1.35 LPM CO2 injection, 1 ata and 13 degrees C/55.4 degrees F. That's somewhat of an issue for me, as (a) it doesn't match CE or NAVY protocol and (b) duration is depth dependent, so 1 ata is utterly insufficent and useless for anyone diving deeper than his bath tub. :11: I certainly wouldn't push that bucket as far as all weekend long.

I'd be careful pushing the scrubber past the 210 minute rating. What you may add in duration due to lower CO2 production you may well lose due to depth. And when the scrubber is exhausted, CO2 levels rise fast. Curves get pretty steep, I've seen them for the Prism and SM1600 scrubbers, and I have the one for the cartridge. Absorbent is cheap in comparison for the price you may pay for a CO2 hit.

Stefan,

All excellent points! Very well put indeed. :rofl:

Rob Davie

 

[Life-Is-Good-Diver]

My experience with them is minimal, I tried an ExtenAir equiped Dolphin in the pool once to see how it breathes. My 20odd hours on the Atlantis when it first came out are so long ago I couldn't really compare, but it seemed decent for the rebreather it is.


Pros: Handling, of course, is brilliantly simple. Chances of channeling much reduced (unless seals are defect), chances of caustic cocktail much reduced since there is pretty much no dust.

Cons: Price, the cartridges started out at $66/box of 4 in 2002, were $78/box last year and are now $120/box. So much for becoming less expensive due to availability for more RBs (first Dolphin, then Azi, now Inspiration ... makes me wonder how they'll charge once the DiveRite hits the market). Not as easy to transport as sorb. Not as easily disposed of as sorb, the plastic cartridge remains and afaik is can't be receycled. They are also harder to find than granular sorb. And finally, testing and rating leaves much to be desired. For a while the verbally stated their cartridges are good for 4 hours, but were willing to only put half of that, 2 hours in writing.


At DEMA I visited the Micropore booth , where they had info sheets available. According to the graph, the CO2 concentration in the loop reaches 0.5% at about 210 minutes. Testing was performed at 40 RMV, 1.35 LPM CO2 injection, 1 ata and 13 degrees C/55.4 degrees F. That's somewhay of an issue for me, as (a) it doesn't match CE or NAVY protocol and (b) duration is depth depended, so 1 ata is utterly insufficent and useless for anyone diving deeper than his bath tub.


I rather doubt that, not even in FL. I certainly wouldn't push that bucket that far.


Dräger/Aqualung's rating for the Dolphin using DiveSorb are available for download in their tech library . They seem a whole lot more reasonable than Micropore's.

Simply put, if you're able and willing to pay considerably more for the advantages listed above, and have the stock scrubber for travel, it may be worth it for you. But I'd be carefull pushing the scrubber past the 210 minute rating. What you may add in duration due to lower CO2 production you may well loose due to depth. And when the scrubber is exhausted, CO2 levels rise fast. Curves get pretty steep, I've seen them for the Prism and SM1600 scrubbers, and I have the one for the cartridge. Absorbant is cheap in comparison for the price you may pay for a CO2 hit.

Thank's again Stefan,

As your post are alway's very helpfull to a rebreather newbie such as myself.

I read all the webiste's and fourm's , decostop, etc, and alway's read alot of your post, as they are very informative and accurate, and very helpfull.

It concern's me, that if i want to just go do two dive's for one day, and maybe only have 2 hour's total, and then i may not dive for another 2 week's,, will the cartridge still be any good? I know the sorb, you fill it right before the dive, and after the 3 and a half hour's, it's done, and once used, even for one dive, it can't be re-used.

Thank's again !

 

[caveseeker7]

Thanks for the kind words.

Dräger has an half-fill insert if you want to do a single dive, or two short ones. Half the amount, not necessarily the time, that's not proportionate.
You should be able to order that through any Dräger/Aqualung dealer. The link will take you to W & S Water Safety in Germany, a big dealer for Dräger parts. You can check it out there. The site is German, but the ship ww and speak English if you can't find it elsewhere.

As for storing sorb in the cannister, I'm not sure what Dräger recommends (propbably buying new Dräger DiveSorb ), but most people do it. Double bag the cannister with date and hours used. I never kept it over a week or two, but probably would up to four. Just don't repack used absorbant, neither an entire or a partial filling (no "topping off" with fresh absorbant).

 

[Life-Is-Good-Diver]

Thanks for the kind words.

Dräger has an half-fill insert if you want to do a single dive, or two short ones. Half the amount, not necessarily the time, that's not proportionate.
You should be able to order that through any Dräger/Aqualung dealer. The link will take you to W & S Water Safety in Germany, a big dealer for Dräger parts. You can check it out there. The site is German, but the ship ww and speak English if you can't find it elsewhere.

As for storing sorb in the cannister, I'm not sure what Dräger recommends (propbably buying new Dräger DiveSorb ), but most people do it. Double bag the cannister with date and hours used. I never kept it over a week or two, but probably would up to four. Just don't repack used absorbant, neither an entire or a partial filling (no "topping off" with fresh absorbant).

Thanks, i'll look them up as well.

I bought the HS Explorer PPO2 Meter , single cell for PPo2 read out's, but i can't find anywhere on their site how to install it and where? I downloaded their link on page 8, and their manual, here:
http://www.hs-eng.com/PPO2 Manual.PDF

But it dosn't show anywhere how to connect the O2 sensor, and the unit?

Does it install in the lung?? Or punch a hole in one of the bag's , like inhale?

Weird, no pictures on how to install it onto the unit it's self, i have the Drager P connection, more home work to do.

By the way, i bought the book off Pipedope, he's an active SB member, called
Mastering Rebreather's , great book, upto chapter 5 now, thank's again !!

 

[carlislere]

I have been using the Extend Air with the Dolphin since last fall. I used the first cartridge for 213 minutes over 4 dives. The dives were in twos about a week to 10 days apart. I have 110 minutes on my second cartridge that I dove a week ago, but I will not dive the rebreather again till next week at the earliest. I plan on diving the same profile again. No complaints so far. Saves some time on assembly and disassembly and cleanup.
I checked into the Extend Air at DEMA. I spoke to the folks at the booth and tracked down Jeff Bozanic on the DEMA floor. I introduced myself and asked him about it. He spoke very favoribly about the Extend Air and he said he had been using it for years with the Dolphin, Azimuth and Inspiration.
There had been rumors that AquaLung may drop Drager. I ran into problems with getting parts when Drager dropped US sales and Aqualung took it over. I couldn't dive the unit for almost two years before we could get parts again. I am covering my six just in case this happens again!

 

[Life-Is-Good-Diver]

I have been using the Extend Air with the Dolphin since last fall. I used the first cartridge for 213 minutes over 4 dives. The dives were in twos about a week to 10 days apart. I have 110 minutes on my second cartridge that I dove a week ago, but I will not dive the rebreather again till next week at the earliest. I plan on diving the same profile again. No complaints so far. Saves some time on assembly and disassembly and cleanup.
I checked into the Extend Air at DEMA. I spoke to the folks at the booth and tracked down Jeff Bozanic on the DEMA floor. I introduced myself and asked him about it. He spoke very favoribly about the Extend Air and he said he had been using it for years with the Dolphin, Azimuth and Inspiration.
There had been rumors that AquaLung may drop Drager. I ran into problems with getting parts when Drager dropped US sales and Aqualung took it over. I couldn't dive the unit for almost two years before we could get parts again. I am covering my six just in case this happens again!

Really, couldn't you go back to the orignal scrubber and dive with that and the sorb?

I have a bid on ebay right now, but if it goes to high im just going to let it go. I only plan on diving the Dolphin for 6-12 month's, as i know im going to get into CCR.
I thought for now the experiance at least getting my feet wet diving a rebreather would be great, but i appreciate the feedback, as i know little about them.

The way you and Stepan describe it, sounds like it wouldn't be as costley as i thought. I was thinking of $130 for 4 cartridges, means $33 about a pc, + nitrox for the tank,another $10, so im at almost $50 for 1 cartridge and 1 tank filled with Nitrox !! But i guess by the time you would compare it, 4 OC tanks filled with Nitrox=$40, plus all the tanks and visual's and hydro's , it's all come's out to the same.

 

[carlislere]

You cannot use the Drager scrubber with the ExtendAir. The refit kit comes with a scrubber that the cylinder fits into perfectly thus not allowing channeling.
If you plan to only use the Dolphin for less than a year, I would recommend you stay with the sorb. It's not worth the cost for so short a use period.

 

[caveseeker7]

The way I read Ron the ExtendAir makes him a bit less dependent on Dräger.

Anyway, in regards to cost, for the CCR the 20 cu.ft O2 costs $10, air diluant is between $5 and free. A scrubber charge costs $16 for 6-12 Sodasorb (though in the future plus shipping), so that's $21 for 5-6 hours locally at recreational depths.

Even to an SCR that compares favorably, to OC Nitrox it's a no-brainer.
For 5 hours I'll need 8 tanks at $10 a fill, that's about 4 times as much.

Annually you have the two onboard tanks, viz and hydro as required, plus three sensors ($225 for 3) O-rings and the usual small stuff. Every 40 hours or so a new $3 battery.