2007, Piran, Slovenia

Environmental Ergonomics XII
Igor B. Mekjavic, Stelios N. Kounalakis & Nigel A.S. Taylor (Eds.), © BIOMED, Ljubljana 2007
discomfort and the lower limits chosen behavioraly 0.73. Interestingly, the Tout perceived as
uncomfortably cold or warm was higher in all trials (albeit not significant) in female subjects
compared to male subjects. In addition, when given control over the temperature of the WPS,
female subjects chose significantly higher temperatures (i.e both upper and lower limits) than
male subjects.
Summary of the results mean (SD) are shown in table 1:
Table 1: Perceptual and behavioral thresholds of thermal discomfort
Warmth discomfort Cold discomfort
Male Female All Male Female All
Perception
of comfort
360
Trial 1 35.3 (3.0) 35.7 (2.6) 35.5 (2.7) 34.9 (1.6) 36.4 (1.9) 35.6 (1.8)
Trial 2 34.4 (3.0) 34.7 (1.6) 35.3 (2.3) 34.0 (1.9) 36.1 (1.2) 35.0 (1.9)
Trial 3 34.2 (2.5) 36.3 (4.4) 35.3 (3.6) 35.0 (2.1) 36.1 (2.0) 35.6 (2.0)
Avg 34.7 (2.1) 35.9 (2.6) 35.2 (2.3) 34.5 (1.8) 36.2 (1.5) 35.3 (1.8)
CV 5.3 % 5.8 % 5.5 % 2.3 % 2.3 % 2.3 %
Behavioral Trial 4 33.5 (0.7) 36.2 (1.3) 34.7 (1.0) 32.3 (0.9) 36.3 (0.8) 34.1 (0.8)
response CV 2.0 % 3.6 % 2.8 % 2.3 % 2.3 % 2.6 %
P 0.06 0.54 0.26 0.01 0.9 0.1
P.Corr. 0.83 0.90 0.84 0.76 0.45 0.73
P, P.Corr.– Refer to statistical difference (Paired T-test) and Pearson correlation coefficient
respectively, between the average Tout in trials 1-3 and the average of Tout in the last 3 occasions the
remote control button was pushed (last 3 high and low peaks).
DISCUSSION
The results indicate that the proposed experimental protocol enabled subjects to identify the
thresholds of warm and cold discomfort in a reproducible manner, and that behavioral
thermoregulatory responses can be measured reliably with an accuracy of 1-2°C.
On average there was a good correlation between the perception of thermal discomfort and
the initiation of behavioral response. The results are in line with previous studies indicating
gender-related differences in thermal comfort (Golja et al. 2005) suggesting that females
prefer higher temperatures for thermal comfort.
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