2007, Piran, Slovenia

Environmental Ergonomics XII
Igor B. Mekjavic, Stelios N. Kounalakis & Nigel A.S. Taylor (Eds.), © BIOMED, Ljubljana 2007
Figure 3. Rectal temperature (n=6). An increase in rectal temperature is observed after 120
minutes (85 minutes in the chamber). The shaded area demonstrates the point in time at which
all the PCM has changed to a liquid state for all subjects.
Figure 4. Subjective sensation of body wetness (n=6). An change in the sensation of body
wetness is observed after 90 minutes.
DISCUSSION
In a warm environment, when protective clothing is worn, there is an interaction
between temperatures in the clothing where the PCM is located, and physiological
heat loss effector mechanisms. When the PCM have changed to a liquid phase, the
temperature of the PCM itself rises. Physiological effector mechanisms follow;
vasodilatation measured as increased skin temperatures at the location, increased
sweating measured as an increase in relative humidity at the location, and an increase
in rectal temperature. The results thus support the hypothesis that the time course of
physiological thermoregulatory heat defence mechanisms will follow the dynamics of
temperature development in the PCM.
178
Temperature ( °C)
Rating ballots:
Rest Start test in the climatic chamber (27 °C, 50% RH)
37,6
37,4
37,2
37,0
36,8
36,6
36,4
0 20 40 60 80 100 120 140 160
6 = body wet;
clothing sticks on the
skin
5 = body wet
4 = chest and back
wet
3 = chest and back
slightly wet
2 = normal dryness
1 = more dry than
normal
6
5
4
3
2
1
Time (minutes)
How does your skin feel?
0
-10 0 10 20 30 40 50 60 70 80 90 100 110 120
Time (minutes)