Mean radiant temperature
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Mean Radiant Temperature (MRT) is the uniform surface temperature of a black enclosure with which an individual exchanges the same heat by radiation as the actual environment considered. It describes the radiant environment for a point in space.
Radiant temperature can be approximated by a black-globe thermometer which measures the effects of radiant and convective heat transfer.
You can find all about thermal comfort and related quantities here.http://dt.fme.vutbr.cz/enviro/Pohoda/thermal.htm