Just curious, I was looking at Co2 Sensors, and I ran across several IR measuring Co2 Sensors with less then 1 sec response times, like this
ICX Photonics manufactures IR gas sensors and emitters for Industrial Safety, IAQ and HVAC applications. and was wondering why something like this couldn't be used in rebreathers? They suck low power (35mW), and either return ppm or %.
The only problem with the sensor is it's pressure sensitive so the sensor would have to be sealed in an IR permeable case.