text: Diffusion is linearly dependent on the partial pressure gradient, but is also temperature dependent, and the current rises about two to three percent per kelvin rise in temperature. A negative temperature coefficient resistor is used to compensate, and for this to be effective it must be at the same temperature as the cell. Oxygen cells which may be exposed to relatively large or rapid temperature changes, like rebreathers, generally use thermally conductive paste between the temperature compensating circuit and the cell to speed up the balancing of temperature.
  Temperature also affects the signal response time, which is generally between 6 and 15 seconds at room temperature for a 90% response to a step change in partial pressure. Cold cells react much slower and hot cells much faster. As the anode material is oxidised the output current drops and eventually will cease altogether. The oxidation rate depends on the oxygen reaching the anode from the sensor membrane. Lifetime is measured in oxygen-hours, and also depends on temperature and humidity
  Applications
  Gas mixture analysis
  The oxygen content of a stored gas mixture can be analysed by passing a small flow of the gas over a recently calibrated cell for long enough that the output stabilises. The stable output represents the fraction of oxygen in the mixture. Care must be taken to ensure that the gas flow is not diluted by ambient air, as this would affect the reading.