ASTM E1461  and ISO 22007-4  specify the requirements of apparatus, test sample, and procedure for thermal diffusivity measurement by the laser flash method. In addition to the thermal diffusivity, , measured using the laser flash method, material density, , and specific heat, , need to be measured from separate experiments, to obtain the thermal conductivity using the relationship . The laser flash method is capable of measuring thermal conductivity over a wide temperature range (−120 °C to 2800 °C ) with measurement uncertainty reported to be less than 3% . The advantages of the method are not only its speed (usually 1–2 s for most solid) but also its capability to use very small samples, e.g., 5–12 mm in diameter . There are, however, some considerations that should be kept in mind before carrying out laser flash measurement. First of all, sample heat capacity and density should be known or determined from separate experiments, which may result in the “stack up” of uncertainties and lead to larger errors. Another criticism of the laser flash method is that the effect of sample holder heating could lead to significant error in the measurements if not accounted for properly . Though laser flash method can be used to measure thin films, thickness of the measured sample is limited by the timescales associated with the heating pulse and the infrared detector. Typical commercial laser flash instruments can measure samples with a thickness of ∼100 μm and above depending on the thermal diffusivity of the sample. For thin film sample with a thickness less than 100 μm, one needs to resort to the 3ω method or transient thermoreflectance techniques developed over the past two decades.