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Discussion Starter #1
I have just lodged a query with SGS Ltd about their certification of the iCCR APOC and its CO2 monitoring system in light of the recent public disclosure by Dave Sutton that the CO2 monitoring system didn't work properly on the production unit he was supplied with.

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The information below was completed in the contact form:
Inquiry Type: General Inquiry
How can SGS help: I have an order for a product certified by your company, an iCCR APOC CCR.

https://www.opensafety.eu/certificates/CE_OSEL_Apocalypse_iCCR.pdf

A user of a production unit Mr Dave Sutton has recently publicly reported that the CO2 monitoring system does not work properly.

Can you please investigate the CO2 monitoring system on the product and advise provide a response to the following questions:
1. Is the certificate still current and valid?
2. Have you been advised of any problems (particularly CO2 monitoring) with the unit which have since been corrected from the production unit used by Mr Sutton?
3. The problems with the production unit predate unit certification date, but I am unaware of any public disclosure by the manufacture or the products Design Authority as to the nature of the problem and what actions have been taken to address these previously undislosed issues.

As SGS Ltd have certified this equipment, I would hope that the certification process would have been sufficiently rigorous to identify any such potential problems and have them addressed prior to certification and release of product to cuctomers.

PLease advise if you wish your response to me kept confidential. Given the criticality of the issue, I would like to release th eresponse to other interested divers.

Thanks for your assistance with this matter.
Tony Quinn


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Query has been sent to the SGS Ltd office identified on the certificate (Worle Parkway).


I await their response with some interest.


Tony
 

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Diving is expensive, live with it!
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An excellent idea - interesting to see what they come back with.

The other question people have hinted at is whether the 61508 bit of the certification is still valid, given that the organisation in the DL/OSEL matrix that holds the certification for that is in liquidation.
 

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Mr potty mouth: Sweeping generalist...............
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does co2 monitoring come under en14143?
From recall the terminology was if present is seen to be working or some such, it's there but the spec was written for inhale not exhale.....
 

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No is the short answer.

The longer answer is that if a warning device does exist it has to activate within +/- 3 mbar under section 6.10.4.2
agreed just read that from the standards but it also states inhale, no mention of measuring exhale gas. and as far as I understand it if there is no en standard then it can be ce tested to a technical file but that can be very ambiguous
 

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more weaselly than a weaselly thing
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I'd imagine the guys at SGS *love* receiving this kind of loaded question on a friday ;)
 
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Jesus don't want me for a sunbeam
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I'd imagine the guys at SGS *love* receiving this kind of loaded question on a friday ;)
They won't care, they'll just use one of their "Dear Gina" templates.
 
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I have just lodged a query with SGS Ltd about their certification of the iCCR APOC and its CO2 monitoring system in light of the recent public disclosure by Dave Sutton that the CO2 monitoring system didn't work properly on the production unit he was supplied with.
Hello Tony,

I suspect that the answer you will receive will say something like "we tested the product against the relevant standard and found that it complied".

I would be fairly certain SGS have done nothing wrong here. The standard probably required that they verify the accuracy of the CO2 monitor in measuring the CO2 level in a sample of gas presented to it. As I have said before I am sure it does this accurately. However, for the reasons that I have outlined in many previous posts, measurement of end tidal CO2 (in other words, the CO2 in the alveolar gas) at the end of the exhale hose is not just a simple case of measuring the CO2 in the gas passing the sensor. This, of course, is the ambiguity that commentators like Brad have hidden behind throughout the entire debate on this issue. As Paul R has stated previously, the standard does not address this issue at all.

Thus, in summary, SGS will have been required to verify that the sensor measures CO2 accurately in a gas sample and I am sure they will have done this. However, this certainly does not mean that the number displayed by the Apoc is an accurate end tidal CO2. Based on the few numbers cited by Brad around the time he and David Sutton were using the units it appeared to be underestimating the true values exactly as I and others predicted it would. Alex appears to have changed the processing algorithm since then but has presented no data to suggest it works. I thus have no idea of its current efficacy, though based on the description of the algorithm I and others are very skeptical. Nor do I have any idea how the manufacturers of the commercial unit (which allegedly uses the same technology) are going to portray it when that is finally released for purchase. They may not call it "end tidal CO2" at all especially if there are any concerns about accuracy. It may be "sold" as a trend monitor or something similar, but I am just speculating here.

Simon M
 

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They won't care, they'll just use one of their "Dear Gina" templates.
SGS Ltd should be happy that it is only a customer and not a coroner asking the questions.

The iCCR might be a dead product, but the umbilical unit using related technology still appears a live project so SGS need to be very cautious in these matters.

Tony
 

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Hello Tony,

I suspect that the answer you will receive will say something like "we tested the product against the relevant standard and found that it complied".

I would be fairly certain SGS have done nothing wrong here. The standard probably required that they verify the accuracy of the CO2 monitor in measuring the CO2 level in a sample of gas presented to it. As I have said before I am sure it does this accurately. However, for the reasons that I have outlined in many previous posts, measurement of end tidal CO2 (in other words, the CO2 in the alveolar gas) at the end of the exhale hose is not just a simple case of measuring the CO2 in the gas passing the sensor. This, of course, is the ambiguity that commentators like Brad have hidden behind throughout the entire debate on this issue. As Paul R has stated previously, the standard does not address this issue at all.

Thus, in summary, SGS will have been required to verify that the sensor measures CO2 accurately in a gas sample and I am sure they will have done this. However, this certainly does not mean that the number displayed by the Apoc is an accurate end tidal CO2. Based on the few numbers cited by Brad around the time he and David Sutton were using the units it appeared to be underestimating the true values exactly as I and others predicted it would. Alex appears to have changed the processing algorithm since then but has presented no data to suggest it works. I thus have no idea of its current efficacy, though based on the description of the algorithm I and others are very skeptical. Nor do I have any idea how the manufacturers of the commercial unit (which allegedly uses the same technology) are going to portray it when that is finally released for purchase. They may not call it "end tidal CO2" at all especially if there are any concerns about accuracy. It may be "sold" as a trend monitor or something similar, but I am just speculating here.

Simon M
Hello Simon,

Thank you for your thoughtful response.

I also suspect that SGS Ltd have some wriggle room, but not for the reason you suggest. Accuracy of measurement of CO2 is but the first requirement, how representative the sample being tested would be an equally basic and obvious requirement (which fails in this case for the reasons you have elaborated on many times).

It is more likely that SGS Ltd will try to use the EN61508 certification as an excuse to have not evaluated the efficacy of the CO2 monitoring system at all (excluded from what they certified).

The problem for SGS Ltd with this argument is that they certified against the Manufacturer's Technical File. It would be expected that field reports from divers would form some part of this documentation (it can't have been all just PDF's). It is hard to believe that if Dave Sutton's splash in a pool could identify problems with the CO2 monitoring, that other divers during their test program had not also found and reported this issue.

Handling of the CO2 monitoring problems needs to be contrasted with DeepLife's handling of the ALBOV freefllow/cracking pressure problem. In the later, reports of problems from divers in their test program were publicly disclosed, as well as actions taken by Deeplife to redesign the ALBOV to rectify the problem.

With respect to the CO2 monitoring problems, there has been until very recently, no public dislosure of a problem despite repeated concerns being raised by people wiith significant expertise in the field; quite the contrary, all public statements have been that there were no problems ("it all works").

The manufacture's file is going to make fascinating reading on this matter in light of recent dislosures. Have Deeplife omitted important information, or did SGS Ltd just not understand what was required?

How Dave Sutton can readily find a problem with the CO2 monitoring that Brad couldn't, is also of concern. It is fortunate Deeplife recalled Brad's faulty CO2 Pod before he was further exposed to harm from a fault he was unaware of. To his credit, Brad did pick up on the ALBOV problem.

Regards,
Tony
 

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Can anyone point me to the relevant area of the threads regarding the reported issue from Dave Sutton regarding the operation of the CO 2 monitor.
 

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Can anyone point me to the relevant area of the threads regarding the reported issue from Dave Sutton regarding the operation of the CO 2 monitor.
It's on another forum, CCRExplorers.
 

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Can anyone point me to the relevant area of the threads regarding the reported issue from Dave Sutton regarding the operation of the CO 2 monitor.
ear u go

seem to have loaded wrong link ,, but cant seem to get rid now ,, Help please (MOD,s )
 

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Hello Tony,

I suspect that the answer you will receive will say something like "we tested the product against the relevant standard and found that it complied".

I would be fairly certain SGS have done nothing wrong here. The standard probably required that they verify the accuracy of the CO2 monitor in measuring the CO2 level in a sample of gas presented to it. As I have said before I am sure it does this accurately. However, for the reasons that I have outlined in many previous posts, measurement of end tidal CO2 (in other words, the CO2 in the alveolar gas) at the end of the exhale hose is not just a simple case of measuring the CO2 in the gas passing the sensor. This, of course, is the ambiguity that commentators like Brad have hidden behind throughout the entire debate on this issue. As Paul R has stated previously, the standard does not address this issue at all.

Thus, in summary, SGS will have been required to verify that the sensor measures CO2 accurately in a gas sample and I am sure they will have done this. However, this certainly does not mean that the number displayed by the Apoc is an accurate end tidal CO2. Based on the few numbers cited by Brad around the time he and David Sutton were using the units it appeared to be underestimating the true values exactly as I and others predicted it would. Alex appears to have changed the processing algorithm since then but has presented no data to suggest it works. I thus have no idea of its current efficacy, though based on the description of the algorithm I and others are very skeptical. Nor do I have any idea how the manufacturers of the commercial unit (which allegedly uses the same technology) are going to portray it when that is finally released for purchase. They may not call it "end tidal CO2" at all especially if there are any concerns about accuracy. It may be "sold" as a trend monitor or something similar, but I am just speculating here.

Simon M

Simon - regarding the CO2 monitoring issue - am I right in thinking that the issue is that for low volume inhalation/exhalation due to the volume in the lungs and windpipe - the peak CO2 concentration doesn't reach the sensor in the apoc and is also diluted due to the volume of gas in the exhale hose?

At larger tidal volumes in your view would this issue go away, and hence if the apoc uses a warning to breath deep ie senses volume expired and warns the user if it falls below a certain level, in your view would this address the issue?


From memory I seem to remember that they were planning to measure the depth of breaths by a temperature sensor in the mouth piece.
 
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