Five relative humidity and temperature sensors (Tianjin meteorological instrument corporation, DHM-2A type, temperature ranges from -36 to +46°c, relative humidity ranges from 10 to 100%) were placed in different locations, 1.5 m above thr floor and out of direct sunlight. Data were recorded at 0800.1400 and 2000 h. Temperature humidity index (THI) was calculated as: THI= 0.72 , where Td is dry bulb air temperature, and Tw is wetbulb air temperature (Thom. 1959).