The thermal conductivity of graphite in molten salt reactors varies based on its form and density, necessitating specific identification of the graphite type for accurate data. Users are advised to consult research specific to the chosen form of graphite, as values can differ significantly. It is important to note that a range of thermal conductivity values may be encountered, prompting the need for sensitivity analysis or the use of average values in modeling. Additionally, cumulative neutron dose (fluence) can affect the thermal conductivity of graphite. Accurate modeling in RELAP5-3D will require careful consideration of these factors.