Thermal conductivity

Mark: λ (lambda)
Unit of Measure: W/mK
A thermal characteristic that indicates how many Watts (W) of energy is released, when a material with uniform thickness (1 metre), in the event of –  1 K (Kelvin) (generally understood: 1°C) temperature difference between its two sides under a unit of time. depending on whether it is assessed from a thermal conductivity or thermal insulation point of view).
The value λ_D or declared (reported) is measured under normal (lab) conditions specified by the Manufacturer. This is different from λT or design value. The design value of the thermal conductivity can be determined by the following means, (with knowledge of the declared value):
λ_T = λ_D x F_T x F_m x F_a
Where:
λ_T = thermal conductivity factor to be taken into account under the intended environmental conditions
λ_D = heat conductivity declared under standard (known) environmental conditions
F_T = temperature correction (conversion) factor
F_m = humidity correction (conversion) factor
F_a = the aging correction (conversion) factor