(2) The globe thermometer. The usual globe thermometer apparatus
consists of a six inch hollow copper sphere painted flat black on the outside and
containing a thermometer with its bulb at the center of the sphere. The thermometer
stem protrudes to the outside through a stopper tightly fitting into a brass tube soldered
to the sphere. The sphere has two small holes near the top used for suspending the
sphere with wire or strong cords. The globe must be kept a dull black at all times, free
of dust or rain streaks, by dusting, washing, or repainting if necessary.
b. The Method of Computing the WBGT Index.
0.7 x wet bulb temperature.
+ 0.2 x black globe temperature.
+ 0.1 x shaded dry bulb temperature.
c. Use of the WBGT Index in Control of Physical Activity.
(1) Measurements must be taken in the same location or a location similar
to the environment in which soldiers will be working, exercising, etc.
(2) Look at table 4-2 for recommendations for physical activity for various
temperatures on the WBGT Index.