Personal factors in thermal comfort assessment: clothing properties and metabolic heat production.

Discusses, in the context of the Predicted Mean Vote (PMV) model, the representation and measurement of clothing parameters and metabolic rate. Identifies several problems and provides solutions to a few. Results showed the importance of the effects of body motion and air movement for clothing insulation, and suggests they should be incorporated into the model. The results also showed only small effect on dry heat exchange for stationary light work at low air movement. Suggests that algorithms for convective heat exchange in prediction models should be reconsidered. Clothing vapour resistance or induced skin wettedness should be included in some cases. Recommends that a precise measure of metabolic rate is also needed. States that methods for determining metabolic rate provided by the current standard (ISO 8996) do not provide sufficient accuracy to allow the determination of comfort in order to classify buildings to within 0.3 PMV units as proposed in the forthcoming revision of ISO 7730.