Temperature range of measurements:

-150°C to 1800°C (the high temperature range is unique for heat insulation and rough materials)

Gas composition and pressure:

Thermophysical properties can be evaluated at any temperature and in a range of different gas atmospheres and gas pressures.
Note that thermal conductivity and diffusivity of materials with open porosity of over 2-5% can change 5-10 times depending on the ambient gas composition and pressure.

Note: One can see a large increase in apparent thermal conductivity at high temperature; extrapolation of low temperature data can give a large error.