Thermal comfort draft

Thermal comfort assessments room air and operative temperatures (bur not draft risk evaluations)... 

Due to the methods and limitations outlined in Section 11.3..3, in thermal comfort analysis, draft risk evaluations cannot be performed using this type of room model. Analysis of air temperature stratification and thermal comfort for the occupant zone can be achieved only by using multi-air-node room models. 

For the models described, the usual assumption for air nodes in regard to the room air distribution is still valid. This means that each air node represents a volume of perfectly mixed air. Thus, the same limitations as for thermal and airflow models apply Local air temperatures and air velocities as well as local contaminant concentrations can he neither considered nor determined. This also means that thermal comfort evaluations in terms of draft risk cannot be performed. 

Thermal comfort may not be attainable because 1) the heat balance is unable to be satisfied for Ts and Esw, or 2) asymmetries such as drafts, asymmetric radiation, etc., exist. Defining the thermal load, L, as... 

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