ExtendAir Absorbant

[carlislere]

Does anyone have experience using the ExtendAir canister and absorbant for the Drager Dolphin? If so, what do you think of the products? Thanks.

 

[caveseeker7]

If so, what do you think of the products?

I've tried it in a Dolphin once.
WOB was fine as Dolphins go, the ease of handling can't be beat. Open cannister, insert cartridge, close cannister. Done. No slow filling, no dust, no tapping. Those are the advantages, especially the lack of dust as it makes the cartridge more resistant to caustic cocktails when you develop a leak.

The downside are the high expense and short duration (which again raises the price/hour). You need to get a replacement cannister that retails for $350. Most people around here use Sodasorb, so I can compare the price to that. I don't know what it would be for Dräger's DiveSorb. But the price of the replacement cannister buys you 3 buckets of Sodasorb, each one good for 7 stock Dräger cannister fills. If you stay at Dräger's consevative scrubber rating of three hours the 21 fills add up to 63 hours of diving ... :11:

And that's just the admission for the use of cartridges.
So far no testing data has been made available to the public, even though the cartridges are used in Dolphins, Azis, Inspirations and at least one Meg. At both DEMA '02 and '03 the company promised testing would be finished soon and available to the public. In conversations the reps keep insisting the cartridges are good for 4 hrs, but will only rate them at 2hrs in writing. And even for that number they didn't disclose any of the relevant test parameters (depth, temperature and CO2 production). So two hours it is, at least in my book, which is 2/3 of what you get from granular absorbant.

A box of 4 retails at$76, giving you 8 hrs dive time. That's $19 per fill and $9.50 per hour. Compare that to the before mentioned Sodasorb. A 37 lbs bucket retails for $90, enough for 7 fills. That's $12.85 per fill and $4.29/hr based on the 3 hrs rating.

So unless the convenience of handling the cartridge is of very high value for you, or money is not an objective in your life, the cartridges don't make a lot of sense. Not at the current price and usefull life, anyway.

If they ever come up with independent testing data for the various applications that show a longer cartridge duration the equations will change in favor of the cartridges. If they increase production and reduce the price it'll be the same.
Both would make them a feasible replacement for granules.

 

[poseidan]

I have about 40 dives on my dolphin, at least half of them using the extend air. I think its great, for me the two biggest positives are the ease of packing and the decreased probability of caustic cocktails. The ease of packing can't be overstated, especially if you are on a boat, takes 10 seconds, open the cansister slide in cartridge, and close it. And you just don't have to worry about dust. WOB, maybe you can tell the difference, I couldn't. I think the shelf life is two years, which is longer than sorb, but I'm not sure about this.

Price depends on how you use it. When I'm doing multiple dives over multiple days, in a warm water location with easy diving then I use them for about four hours. This makes it more price competive with sorb. Generally don't use it for my cold water diving, where my dive times are shorter and not doing diving over multiple days. I do half packs of sorb in this case, then the cartridge, which only comes in a full pack(they are working on a half pack), is not price competive with sorb. And since its cold water I like doing sorb changes more often.

The service from Micropore has been great, I usually have them ship to cartridges to where I'm diving, as long as it is a developed location, US or Carib. That way I don't have to worry about the transport. I know Dive Tech on Grand Cayman stocks them, but not many other places in the Carib have them.

If you have any other questions just PM me.

 

[caveseeker7]

WOB, maybe you can tell the difference, I couldn't.

I couldn't either, that's what I ment.
I'm just accustomed to o-t-s bags which feel different than the Dräger's backmounted ones.

Price depends on how you use it. When I'm doing multiple dives over multiple days, in a warm water location with easy diving then I use them for about four hours.

Under those conditions Dräger rates the Dolphin's scrubber duration at four hours, too. So the cost per hour on the cartridge is down to $4.75, for granules it would be about $3.25 ... getting a lot closer.

At that price the ease of handling makes it worth consideration.
I hope Micropore manages to produce the promised 4hrs cartridge (and data - just doubling the rating on my own would keep me nervous throughout the dive). At least for CCR applications that would be a step forward.