Table 1.

Standard range of temperature humidity index and index of wind effect

	THI	K
Extremely cold	< 40	< −1200
Cold	40–45	−1000 to −1200
Very cool	45–55	−800 to −1000
Cool	55–60	−600 to −800
Comfort	60–65	−300 to −600
Warm	65–70	−200 to −300
Very warm	70–75	−50 to −200
Hot	75–80	80 to −50
Extremely hot	> 80	> 80