The Relationship between the Heat Disorder Incidence Rate and Heat Stress Indices at Yamanashi Prefecture in Japan

Table 3

The temperature thresholds of heat stress indices in each region. Abbreviations are the same as those in Table 1.

Heat stress indices	Daily max. air temp.; (°C)	Daily max. WBGT; (°C)	Daily max. WBGT; (°C)
Class interval width	Const.	Const.	Various
KF	37.4	32.5	31.4
KH	33.9	30.1	29.8
KN	34.2	31.6	31.4
KT	35.7	31.7	31.7
TB	34.3	31.5	31.4
FG	30.4	28.3	28.2

The class interval width of the heat stress index is 1°C.
The class interval width of the heat stress index was calculated from the regression equation derived from the relationship between air temperature at daily maximum WBGT and daily maximum WBGT.