In severe heat strain, the heat stress index (HIS) is -
Heat stress: Heat stress is the burden of the heat that must be dissipated if the body is to remain in thermal equilibrium. The amount of heat gained by the body must be equaled to the amount of heat lost from it. Heat stress index represents the % of the heat storage capacity of an average man. HSI values are 0 - no thermal stress 10-30 - moderate to mild heat strain 40-60 - severe heat strain 70-90 - very severe heat strain 100- the upper limit of heat tolerance
30-Oct
40-60
70-90
100
Environment and health