Inexhaustible CO2 Eliminator

[padiscubapro]

Ok looking through the CE standards here is what I see

there is actually a table of various ventilation rates, tidal volumes ect..
there are various levels of inspired co2 that must be tested these are
0.4, 0.9, 1.6, 2.5 and 3.0, the ventilation rate varies from 10lpm to 75lpm depending on the test, the 1.6 rate requires 40lpm rate(and an oxygen consumprion rate of 1.70lpm).

the test must be done at 4 degrees c, (it appears the co2 measurement is done under the general testing conditions - although not explicitly stated, I would like this clarified) for nitrogen/oxygen mixtures done at 5 bar while helium/oxygen tests must be run at 11bar

the official endurance is rated using the 1.6 lmp figure, and time has to be recorded when pco2 reaches 5mbar and 10mbar

 

[madmole]

Thanks PadiScubaPro

Did you buy a copy then or scrounge a set, and is there any way I can get my hands on a copy without bankrupting myself?

Any other good stuff in there?

How did the UK diving go, did you get to do much with the weather we had that week or were you forced to retire and drink beer

 

[caveseeker7]

BigJetDriver69 once bubbled...
Hello All!

I kept wondering why "Shas" is such a passionate defender of Steam Machine's Prism (et al).

Then, of course, I thought to look at the profile page. (Duh!--Sound of hand striking forehead!)

She certainly must be expected to be passionately partisan toward her company's product. One should keep this in mind when reading her posts.

Good work, Sherlock.
Shas probably is biased, who wouldn't be when your product keeps getting shot at ... and sometimes quite cheaply at that.

But there is another side to it: You've got access to the manufacturer.
Who better to answer questions? I think that's great, and outweights any bias she might have. And, having met her a couple of times and talked with her, I can tell she's both a nice person and has an unbelievable amount of knowledge about rebreathers. :wacko:

If you scroll through the posts you'll find several of users, too, and they seem to be quite happy with their units.

Besides, most people here seem to be passionate about their units, Madmole about his Inspiration, db8us about his RB80 etc. .


As for Nicky Finn, other than the yellow box itself she's probably APD's biggest asset.

 

[madmole]

OK, here is the relevent section of the CE regs
####################################

Maximum inspired partial pressure of carbon dioxide

The volume-weighted average inspired partial pressure of carbon dioxide shall not exceed 20 mbar. This shall be

fulfilled during the full endurance time of the apparatus specified by the manufacturer.

Carbon dioxide absorbent canister

The endurance of the charged carbon dioxide absorbent canister in water at (4 ± 1) °C shall be stated by the

manufacturer for each specified absorbent material. It shall maintain an end of inspiration partial pressure of carbon

dioxide of less than 5 mbar.

Testing shall be done in accordance with 6.6.1 and 6.6.2.

Inhalation temperature

The maximum inspired gas temperature shall be less than 40 °C.

If fitted an inspired carbon dioxide monitor shall have an accuracy under all conditions within ± 3 mbar and warn the

diver when inspired carbon dioxide exceeds 5 mbar.

In the event of a failure of any active warning device it shall fail so as to warn the diver. The FMECA shall be used

to identify the appropriate device.

Monitor for inspired partial pressure of carbon dioxide

Test the monitor of the inspired partial pressure of carbon dioxide by exposure to partial pressures of carbon

dioxide in the range 0,0 mbar to 30,0 mbar in increments of 5 mbar. The test shall be repeated at pressure

increments of 1,0 bar from 1,0 bar to the maximum pressure (depth) of the apparatus. The monitor shall read within

± 3 mbar of the impressed partial pressure of carbon dioxide.

Volume weighted average inspired carbon dioxide

Determine the volume weighted average inspired carbon dioxide under the conditions in accordance with 6.3.1 with

carbon dioxide injected into the exhaled gas from the breathing simulator at the rates shown in table 4.

Measure the inspired carbon dioxide at the mouth with an analyser having a response time of less than 150 ms to

95 % of the step change. The monitored carbon dioxide level should then be integrated with respect to the volume

of gas inspired rather than the time of inspiration.

Carbon dioxide absorption endurance

Maintain the exhaled gas at 30 °C ± 2 °C and a relative humidity greater than 80 %.

Test the apparatus with the breathing simulator ventilating at 40 l min-1 and carbon dioxide injected into the exhale

gas from the breathing simulator at a rate of 1,6 l min-1.

Record the time taken for the end inspired partial pressure of carbon dioxide to reach 5 mbar and 10 mbar.

On completion of the test invert the apparatus in -90° position for 1 min and measure the pH value of any water

present at the facepiece. The pH value shall not exceed 9.
##############################

Hope that helps

Yes, Shas is an assett to this forum, We have plenty of people who know the Yellow box, but few are really knowledgeable about the Prism, MEG, KISS etc, we seem to have a few RB80 folks around. Its only by exchanging info that we dispel our misconceptions about the other units. Also seems to be a lack of active Dolphin users here which is suprising considering their popularity and cost

 

[fins wake]

Guys and gals, I'm enjoying this thread immensely, it's informative and - IMHO - not a flame thread at all. Shas, you're making a valuable contribution (as is Madmole and others), so please stay on the board.

You've made some very good points. Unfortunately, this doesn't extend to your comments on the European market.

CE may be relevant to your market, but sorry Europe isn't the only market. Yes, it's a large one, but it's also saturated,

It isn't as a matter of fact, not even close. Only in the United Kingdom has there been there been anything approaching a true mass-market following. There are still several thousand dedicated deep wreckies in Italy, France, Scandinavia and Germany, just to pick a few examples, who would benefit from a CCR. But remember, it has to be CE-certified over here.

I'm impressed by the PRISM:s performance in the US Navy trials, and of course it means a lot to prospective purchasers and civilian users, too. But it still doesn't give SMI the European market ... which is way ahead of the US market. (This is useful for setting the correct strategies in the US later, BTW.)

None of this detracts from the Inspiration. This isn't a zero-sum game. There's room for many good RB:s out there. That's the goal. The "zero-sum" aspect shows in itself that the market is way too small right now.

Anyway, perhaps a small hint for future CE-certification trials ...I believe that the PRISM has a very similar scrubber to that of the DCSC ... There you go, Shas!

Madmole, Shas, Caveseeker, Padiscubapro et al, keep up the good work!

 

[saturated]

Thanks guys,

This thread has been very informative. Shas welcome aboard. I dive several different units and find them all to be good in their own right. I think competition is what will bring the quality and safety of these units up. There are so many things I like about so many different units. I love the analog back up on the prizm, great idea. Got me thinking about an anslog gauge for my inspiration, just in case. Shas please dont leave the board, as we can all learn from you. This site for me is all about knowledge, not the "my dad is bigger than your dad" statements. Most of the breathers posted on here are fine units and definately have there place. I'm not sure what the best breather is.

It's like saying the Corvette is the best car. Not if you live on a dirt road it is'nt.

thank you all for your hard work and information provided.

 

[padiscubapro]

madmole once bubbled...
OK, here is the relevent section of the CE regs
####################################

Maximum inspired partial pressure of carbon dioxide

The volume-weighted average inspired partial pressure of carbon dioxide shall not exceed 20 mbar. This shall be

fulfilled during the full endurance time of the apparatus specified by the manufacturer.

Carbon dioxide absorbent canister

The endurance of the charged carbon dioxide absorbent canister in water at (4 ± 1) °C shall be stated by the

manufacturer for each specified absorbent material. It shall maintain an end of inspiration partial pressure of carbon

dioxide of less than 5 mbar.

Testing shall be done in accordance with 6.6.1 and 6.6.2.

Inhalation temperature

The maximum inspired gas temperature shall be less than 40 °C.

If fitted an inspired carbon dioxide monitor shall have an accuracy under all conditions within ± 3 mbar and warn the

diver when inspired carbon dioxide exceeds 5 mbar.

In the event of a failure of any active warning device it shall fail so as to warn the diver. The FMECA shall be used

to identify the appropriate device.

Monitor for inspired partial pressure of carbon dioxide

Test the monitor of the inspired partial pressure of carbon dioxide by exposure to partial pressures of carbon

dioxide in the range 0,0 mbar to 30,0 mbar in increments of 5 mbar. The test shall be repeated at pressure

increments of 1,0 bar from 1,0 bar to the maximum pressure (depth) of the apparatus. The monitor shall read within

± 3 mbar of the impressed partial pressure of carbon dioxide.

Volume weighted average inspired carbon dioxide

Determine the volume weighted average inspired carbon dioxide under the conditions in accordance with 6.3.1 with

carbon dioxide injected into the exhaled gas from the breathing simulator at the rates shown in table 4.

Measure the inspired carbon dioxide at the mouth with an analyser having a response time of less than 150 ms to

95 % of the step change. The monitored carbon dioxide level should then be integrated with respect to the volume

of gas inspired rather than the time of inspiration.

Carbon dioxide absorption endurance

Maintain the exhaled gas at 30 °C ± 2 °C and a relative humidity greater than 80 %.

Test the apparatus with the breathing simulator ventilating at 40 l min-1 and carbon dioxide injected into the exhale

gas from the breathing simulator at a rate of 1,6 l min-1.

Record the time taken for the end inspired partial pressure of carbon dioxide to reach 5 mbar and 10 mbar.

On completion of the test invert the apparatus in -90° position for 1 min and measure the pH value of any water

present at the facepiece. The pH value shall not exceed 9.
##############################

Hope that helps

Yes, Shas is an assett to this forum, We have plenty of people who know the Yellow box, but few are really knowledgeable about the Prism, MEG, KISS etc, we seem to have a few RB80 folks around. Its only by exchanging info that we dispel our misconceptions about the other units. Also seems to be a lack of active Dolphin users here which is suprising considering their popularity and cost

I am guessing someone got you a copy of the new ce rules.. let me know if you dont have the entire document

 

[BigJetDriver]

caveseeker7 once bubbled...


Good work, Sherlock.
Shas probably is biased, who wouldn't be when your product keeps getting shot at ... and sometimes quite cheaply at that.

____________________________________________________

I appreciate the snide bit about "Sherlock", Caveseeker, but it was I who pointed out originally that I should have looked at the profile first.

I am glad that you felt it necessary to reiterate MY point that, while she would of course be biased, that fact did NOT negate the value of her information. I also stated that I did not know the lady personally. I will take your remarks about her personality and character to heart.

As for your comment about Nicky Finn, I could not agree more!