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iain-hsm · 14th September 2006, 14:59

Quote: (Originally Posted by jaap)

A liter of water from one Extendair cartridge!? If my chemistry is not wrong that would translate into something like an absorption of ~1400l CO2!

This is under the assumption that absorption of 1 CO2 makes the scrubber produce approx 1 H20.

Also if that much water is produced and not retained in the cartridge matrix how come the Extendairsystem is designed the way it is. The conical and O-ring sealed part in the ends of the scrubber should trap the water inside the cartridgecompartment? For me it looks like the system as it is today does not have any means to separate any water formed inside the cartridge from the cartridge?

I have an Extendair-scrubber but I don't use it since it is such a hassel to get cartridges to Sweden or any EU country.

Do you have any idea if the Extendair system will be sold in the EU anytime soon?

I would assume during the breathing trials 100% humid air or gas is used. The effect of temperature and humidity on breath samples is also an effect on the amount of water used by the humidifier to create the 100% humidity. I suggest the amount of distilled water consumed by the humidifier should be noted and in addition disclosed if it is at the 1.6 l/min C02 rate that is driving the chemical action.

The effect of humidification and warmed air or dry and cold air on the accuracy of a canister duration trial is the most interesting part to me, It shows the importance of a reference model using a conventional agreed system, IMHO that model should be examined to a referenced lung model but I can live with BS EN. (have to?)

Constancy of the values set for temperature, relative humidity and absolute humidity in the lung model if given for all measurements in both the dry and cold air tests would give a better understanding between granular type absorbents and the fabric deposited absorbents. But design considerations of the breathing bags also have a marked effect on the amount of water getting to the canister. However non more than a "hot" lime. Most granular limes are around 14% to 17% effective (Hot) if the cartrige type has increased the potency of the chemical by 30% one would expect a corresponding increase in C02 uptake. Iain Middlebrook

14th September 2006, 14:59	#23 (permalink)
iain-hsm Custom Title Allowed! Current Rebreather/s: MK 15.X Other CCR Other SCR Other Rebreather/s: Other CCR Other SCR Join Date: Mar 2005 Location: Loughborough England uk Posts: 347	Re: Extendair Quote: (Originally Posted by jaap) A liter of water from one Extendair cartridge!? If my chemistry is not wrong that would translate into something like an absorption of ~1400l CO2! This is under the assumption that absorption of 1 CO2 makes the scrubber produce approx 1 H20. Also if that much water is produced and not retained in the cartridge matrix how come the Extendairsystem is designed the way it is. The conical and O-ring sealed part in the ends of the scrubber should trap the water inside the cartridgecompartment? For me it looks like the system as it is today does not have any means to separate any water formed inside the cartridge from the cartridge? I have an Extendair-scrubber but I don't use it since it is such a hassel to get cartridges to Sweden or any EU country. Do you have any idea if the Extendair system will be sold in the EU anytime soon? I would assume during the breathing trials 100% humid air or gas is used. The effect of temperature and humidity on breath samples is also an effect on the amount of water used by the humidifier to create the 100% humidity. I suggest the amount of distilled water consumed by the humidifier should be noted and in addition disclosed if it is at the 1.6 l/min C02 rate that is driving the chemical action. The effect of humidification and warmed air or dry and cold air on the accuracy of a canister duration trial is the most interesting part to me, It shows the importance of a reference model using a conventional agreed system, IMHO that model should be examined to a referenced lung model but I can live with BS EN. (have to?) Constancy of the values set for temperature, relative humidity and absolute humidity in the lung model if given for all measurements in both the dry and cold air tests would give a better understanding between granular type absorbents and the fabric deposited absorbents. But design considerations of the breathing bags also have a marked effect on the amount of water getting to the canister. However non more than a "hot" lime. Most granular limes are around 14% to 17% effective (Hot) if the cartrige type has increased the potency of the chemical by 30% one would expect a corresponding increase in C02 uptake. Iain Middlebrook
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