excerpt: “Three methods were used to evoke a sensation of warmth at the threshold level: (1) by increasing the intensity of the radiant heat falling on the skin over that from the solid surroundings of the cubicle by an amount which was just sufficient to evoke a sensation of warmth, and obtaining values of such threshold intensities for various areas of skin; (2) by exposing the skin to a stream of air moving at one of several velocities and determining the increase in air temperature above that in the cubicle required to evoke a sensation of warmth; and (3) by increasing the intensity of the radiation falling on the skin, and simultaneously exposing the skin to a stream of moving air.”
Source: Turner, D., Radiative and convective stimuli of threshold intensity, Environmental Hygiene Research Unit, M.R.C. Laboratories, Hampstead, London, N.W 3, J Hyg (Lond),1955 March; 53(1): 32–49. <http://www.ncbi.nlm.nih.gov/pmc/articles/PMC2217808/>
RBc: I love these old studies because much of what we know today in the world of architecture which relates to occupant comfort, comes from this type of research work. A few statements that are of interest from this paper include:
- "On the whole, a change of 1 C. in air temperature is equivalent to 1.40 C. change in mean radiant temperature in its effect upon thermal sensations."
- "Bedford & Warner (1939) found that changes in both the average value and the variability of the air speed and in the temperature had a marked effect upon impressions of freshness."
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