gianaameri
gian @ gian.ameri.name
I have in the last year or so experimented with a novel CO2 sensor mounted on the inhale side, in a modified Meg inhale counterlung, and it works very well.
No false alarms, and accurate enough for the purpose of alerting the diver when CO2 increases over a pre-set alarm amount of choice (i.e. 0.5%).
It is fairly resistant to humidity induced errors, provided it is inserted in the rebreather just before the dive, and removed from the rebreather after the dive (i.e. it is not left unnecessarily exposed to the loop humidity during transport and storage), and of course is placed in a proper location in the rebreather (not where the O2 Cells normally are).
Provided the above pre-cautions are used, it can go several hours without drifting away (usually up when it drifts) from humidity.
The product is now sold and available from a well known and reputable manufacturer, but it will not work for a number of reasons as an end-tidal CO2 monitor (i.e. on the exhale side).
I'd like to give heads-up to all homebuilders (and rebreather manufacturers) that I am working (thanks to a tip from a fellow diver through internet forums) on an end-tidal CO2 monitor based on a different technology and research. It utilises a dermal infrared sensor made by Sentec.
Recent research has shown that the measurement of transcutaneous carbon dioxide at the infraclavicular site is feasible with a digital sensor and has a good correlation with the carbon dioxide values obtained from the arterial blood gas.
I have no commercial interest in diving and the rebreathers business and I am sharing this "tip" publicly so that the more people start experimenting with this technology for our application, the sooner it will become available to all, the cheaper and the better it will be.
No false alarms, and accurate enough for the purpose of alerting the diver when CO2 increases over a pre-set alarm amount of choice (i.e. 0.5%).
It is fairly resistant to humidity induced errors, provided it is inserted in the rebreather just before the dive, and removed from the rebreather after the dive (i.e. it is not left unnecessarily exposed to the loop humidity during transport and storage), and of course is placed in a proper location in the rebreather (not where the O2 Cells normally are).
Provided the above pre-cautions are used, it can go several hours without drifting away (usually up when it drifts) from humidity.
The product is now sold and available from a well known and reputable manufacturer, but it will not work for a number of reasons as an end-tidal CO2 monitor (i.e. on the exhale side).
I'd like to give heads-up to all homebuilders (and rebreather manufacturers) that I am working (thanks to a tip from a fellow diver through internet forums) on an end-tidal CO2 monitor based on a different technology and research. It utilises a dermal infrared sensor made by Sentec.
Recent research has shown that the measurement of transcutaneous carbon dioxide at the infraclavicular site is feasible with a digital sensor and has a good correlation with the carbon dioxide values obtained from the arterial blood gas.
I have no commercial interest in diving and the rebreathers business and I am sharing this "tip" publicly so that the more people start experimenting with this technology for our application, the sooner it will become available to all, the cheaper and the better it will be.
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