to study, develop and advise the CCT on issues related to optical methods for temperature measurement, including the reporting of uncertainty budgets;

to maintain good links/interface with the radiometry community; and

to provide formal liaison between the CCT and CCPR.

Working Group 5 is tasked with producing a document on uncertainty in radiation thermometry at temperatures below the Ag freezing point, with the coordination of thermodynamic measurement results at higher temperatures, with continuing the examination and coordination of activities related to high-temperature fixed points, and with providing appropriate input into the mise en pratique for the realization of the kelvin.