Rebreather Comparison Chart

caveseeker7

Makes sense Paul, I understand what you're saying.
And that this position certainly puts your unit at a disadvantage.

Two thoughts:

First, don't worry too much about those numbers. Steam Machines had theirs, they were good, published them unlike any competitors and few people bothered. The Meg and Kisses have been selling like hot cakes in Europe without CE, and worldwide without solid testing data. So has your unit. I rather doubt that will change.

I have a Sport Kiss and am happy with it. Doubt I sell it because the Ouroboros last longer and breathes with less effort.

Your customer seem to be happy, the unit seems to work for them.
If you want to prove just why that is no one (except maybe your banker) is keeping you from repeating the test for your (and any other unit for that matter) in any other position.

And so the second thought, not just directed at you, but at anyone selling any rebreather:

So far CE testing has always had CE certification as the goal.
Make the information, the data, the results, the knowledge the goal!
That is the important part of it after all.
Don't do the testing to get a sticker, do it to get the data and to get that data to your customers.

Saying a mCCR or a pSCR can't get certified hence we don't test is just plain wrong.
To say we don't need to sell through shops in Europe to cater to that market, or we sell all we can build elsewhere
is just a lame excuse for not supplying proper and important information to divers.
And maybe sometime soon in the future just isn't going to suffice anymore.
Not because EC requires it, but because the customer does.

__________________
Cheers
Stefan


Be Water, My Friend - Bruce Lee

Sponsor Lou in Race For Life!

bendomatic

given that there is no description of how the data was measured on the poster with the data presented then that data is meaningless and just manufacturer hype.
rachel

__________________
why deal with idiots on the net when you have to spend all day dealing with them at work.

caveseeker7

Nonsense, safe for the position of the units during the breathing resistance test all other info was supplied.

__________________
Cheers
Stefan


Be Water, My Friend - Bruce Lee

Sponsor Lou in Race For Life!

schford

Its my crappy photgraphy!!! Let me chase up the PDF.

__________________
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

caveseeker7

Thanks Stuart.

I got a bunch of pictures of the chart that should cover most all of it,
but I need to get them in my computer first, run a filter or two, crop and resize them, and the earliest I (hope I can still) do that would be tonight sometime.

PDF would be much better and quicker.

__________________
Cheers
Stefan


Be Water, My Friend - Bruce Lee

Sponsor Lou in Race For Life!

AD_ward9

This is not true. If it is CE data then the test conditions are laid out very clearly in EN14143:2003.

It is good that CCR Ltd have published this data.

There are some anomalies though, which are worthy of discussion. The Optima result is a particularly interesting one. The Optima is designed for 1.35l/min of CO2 for 3 hours. If RMV is maintained at an unrealistic level, it will break through MUCH earlier. The CE level of 1.6l/min of CO2 is unrealistic, and it causes off effects here.

Every scrubber has a maximum amount of CO2 it can absorb and a maximum amount per unit time. This means that where the gas flow is not even, as in the Optima, one part of the EAC can break down due to exceeding its CO2 per unit time figure. That is what probably causes the result CCR publish here. If they switch off the breathing machine for 5 minutes and restart, the scrubber probably comes alive again.

On the points people make about WOB and hydrostatic pressure, these two are quite separate. The WOB tests at 0 and 90 degrees optimise the loop pressure, so any hydrostatic issues should be cancelled out where the CL centroid is higher than the Suprasternal notch simply by adding gas to the loop, but are not cancelled out if the CLs centroid is under the Suprasternal notch. The lung centroid is a much better reference point and much more accurate anatomically.

Alex

lancsman

In the interest of fairness and also to try and get some more information can anyone with inside contacts get the other manufacturers to comment on the results and post their own if they have them. If they won't then we must accept the results as correct (because they would shout if not)

Just a thought.

Mark

paulraymaekers

and this one:

rEvo 142 minutes ouroborus 154 minutes

efficiency: rEvo BETTER than ouroborus: meaning the rEvo had LESS sorb in the unit then the ouroborus ... why??

the rEvo can take more kg sorb in the scrubber (2.8kg sofno fine grade) then the boris, so why was it not completely filled, according to manufacturing specs?

according to the data, with a correct filled canister, the rEvo would have given minimum 162 minutes (with 2.8kg stead of 2.45 kg)

paul

(difficult to hide that he's a bit... grrr)

__________________
www.rEvo-rebreathers.com

.... the earth is flat, Elvis is alive, and radial scrubbers give longer dwell time than axials...

schford

It was explained to me - that if the CO2 rate was lowered than the other scrubbers would do proportionally better too. So again the cartridge would be last? Is this wrong (I understand the basic theory behind it all but dont profess to be an epxert or have played with test equipment)?

Or does the amount of CO2 really make a difference with some designs more than others? I believe the Optima was designed with a target of 1.35l of CO2 rather than the 1.6 of CE and that makes the difference as no one is going to product 1.6l of CO2 for hours...


Now I just need to find out how my Meg Radial scrubber does :-) as the WOB is excellent!

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

AD_ward9

I will email Kevin and see if he is interested at doing a back to back comparison. It would mean we could each claim figures that have been independently verified.

We have a radial Meg scrubber here, so can include that.

On the scrubber point, it is not a proportional breakthrough. That is, if you exceed the CO2/min figure, you get breakthrough, and it is completely independent of the scrubber duration. That is what almost certainly gave the figure here.

Martin Parker made comments about getting a similar figure to me at DEMA last year, for the Inspo cartridge with EAC adapter. That has a similar side entry for the gas as the Optima, and we found in our own designs that if the flow is not even then you get this very early breakthrough. The EACs are more susceptible to this design fault because once in a channel, the flow has now way of evening itself out. When people see this but have not understood the cause, they tend to arrive at off the mark conclusions as to the EAC's potential. It is essential the flow cones do actually achieve even flow with EACs, otherwise though they work for 3 hours or so at 1.35l/min CO2 they can break down very early, temporarily, at 1.6l/min. Just shaking the unit or stopping the gas flow for a few minutes restores it. The only conclusion is one needs to measure scrubber endurance with a range of flows, as it is in NORSOK U-101 rather than in EN14143, to get a true comparison. I will include that in my suggestion to Kevin, as we do NORSOK tests anyway and getting more reference points would be useful to us.

Alex