2007, Piran, Slovenia

Manikins
Figure 3: Comparison among theoretical heat needed to warm all the refrigerants in the
cooling vest, real extra heat supply until steady state and that during the first 3 hours
(a) (b)
T em perature( )
40
38
36
34
32
30
28
Heat (K cal)
80
70
60
50
40
30
20
10
0
0 5 10 15 20
Time(Hour)
Type A Type B
150
125
100
75
50
25
0
Heat Flux(W /m 2 )
under
refrigerant 1
under
refrigerant 2
under
refrigerant 3
not under
refrigerant
Heat Flux
Theoretical heat
needed to warm a l
the refrigerants in
torso
Heat supplied until
steady state in
torso
Heat supplied during
the first 3 hours in
torso
Figure 4: Skin temperatures at each point covered by refrigerant 1, 2 and 3 and a noncovered
point by refrigerant in stomach. The stomach zone was covered by 3 pieces of
refrigerant. Under each refrigerant, thermistors were placed onto the skin: (a) cooling by vest
having Type A, (b) cooling by vest having Type B.
Skin temperature under type A refrigerant rose more slowly than type B. At a non-covered
point by refrigerant, skin temperature under type B was higher than type A in the early state
of cooling (Figure 4).
DISCUSSION
By using a manikin, the cooling efficiencies of two types of refrigerants were investigated
with fire-fighter’s clothing. The cool vest with 16 packs of refrigerant was dressed on torso of
the thermal manikin in a T-shirt. Though type A refrigerant (100% paraffin) had larger heat
capacitance than type B refrigerant (50% paraffin + 50% water), type A had less cooling
efficiency than type B during the first 3 hours. It is considered that type B absorbed more heat
in the early stage, because it changed the shape to fit the manikin surface, as it was gel. In
contrast, type A was solid, and it would be difficult to fit well to the manikin surface.
ACKNOWLEDGEMENTS
This study was supported in part by the Research Grant for Fire and Disaster Management in
Japan.
Tem perature( )
40
38
36
34
32
30
28
0 5 10 15 20
Time (Hour)
150
125
100
75
50
25
0
Heat Flux(W /m 2 )
under
refrigerant 1
under
refrigerant 2
under
refrigerant 3
not under
refrigerant
Heat Flux
449