PURPOSE: To achieve a compact size and a light weight, convenient in transport and with lower equipment cost by accomplishing all kinds of testings in a single testing tank.

CONSTITUTION: In testing for temperature and humidity, air humidified with a humidifier 11 and heated with a heater 13 is sent to a testing tank 16 via an air blowing port 14 with a blow fan 12 to adjust the temperature and humidity by a circulative air blowing, where the humidifier 11 is provided a heater underwater. Air cooled with a cooler 25 is introduced into the tank in the testing for low temperature and outside air done so in the testing for drying by heated air with a blower 23 while air in the tank is blown in a circulative manner with the blow fan 12 and at the same time, it is heated with the heater 13. In the testing for spray of salt water, a salt water is sprayed from a spray column 15 to promote deterioration of a sample 4. But the blow fan 12 is stopped and in stead, the temperature adjustment in the testing tank 16 is performed with a heater 26.