[PSUBS-MAILIST] life support method?

[Alec Smyth <Asmyth@changepoint.com>]

	Guys,

	I can see the obvious merit of having an O2 sensor to know whether
the air you are breathing is good or bad. But why is it necessary to have it
tied back to the replenishment system, with a solenoid, etc.? Surely you can
just have a tank of O2 with a demand regulator attached (a scuba reg), which
would replenish O2 automatically as it is absorbed by the scrubber. This
would appear to be pretty simple. Am I overlooking something?

	-Alec