(1) will be a temperature index, i.e. the air temperature of a reference environment that provides the same heat exchange conditions as the actual environment under consideration,

(2) should cover the whole continuum of thermoregulation. That implicates that there is a relative wide range of thermal conditions within which people theoretically are able to adapt by behaviour (here: clothing) in order to keep comfort,

(3) will deal with total body conditions as well as with bare skin problems to avoid frostbite risks,

(4) will be based on the most advanced multi (65)- node models of human thermoregulation.

Ad (2): It is assumed that people adapt by clothing more or less reasonable to the thermal environment in a wide range of heat exchange conditions in order to achieve thermal comfort (probably 0.5-2.0 clo). Outside the theoretical comfort range the clothing value will be kept fix.

Ad (3): This requires at least a model that distinguish between bare skin and covered compartments. It seems reasonable to revert to an already published model. However, it is understood that everybody can use any model that fulfils demonstrably and sufficiently the model comparison (see 4).

Ad (4): The some thousand simulation results of Dusan Fiala's et al. 65-node model (combinations of Ta, Tmrt, v, rh, clo) available for comparisons as Excel files. Richard de Dear took care to manage comparable input conditions for the Japanese Tanabe 65-node model. So I bargain for the results shortly. Unfortunately the American Berkley group was not able to participate. So the physiological data base is defined by the two mentioned model outcomes plus the findings of the Michel Ducharme/ Randall Oschewski institute for the very cold end.