Quote: (Originally Posted by
AD_ward9)
The same as a PSR, except electronically. This means for each breath, it gives you a certain amount of O2. On changing depth it compensates for lost O2, or extra dil. If you dil flush, ignores it and tries to keep steady state PPO2.
The sensor across the scrubber measures the tidal volume and respritory rate.
On the sensors, stopping them failing high is a long set of issues. We will try and get out that Five Year O2 sensor study we have into the public domain.
Alex
Ok, that I understand, but the actual O2 consumed by the body (and thus needing to be replaced) is a function of workload and can vary by a factor of 1000% from "at rest" to maximum exertion. While tidal volume and breathing rate IS related to this, the correlation is not exact
and is subject (to some degree) to voluntary override in the upward direction (that is, you can "overbreathe" compared to actual metabolic demand voluntarily - or involuntarily if due to fright, etc - even though that may not be correlated to actual exertion and thus metabolic requirements)
So if I have no working sensors and "breathe deep and frequently" compared to my workload, will the OR send the loop hyperoxic, thinking that I have a higher metabolic demand than I really do? Or, if I'm exerting myself, will it send it
hypoxic, not knowing because the O2 sensors are offline?
I guess what I'm failing to understand is how the system can hold setpoint for up to 30 minutes without a direct reading when, from what I can discern, all the indirect means of trying to figure it out aren't going to be correct?