C.2 Temperature and humidity contro

C.2 Temperature and humidity controlC.2.1 Because of the sensitivity to temperature of some fabrics,accurate,close control of the test temperature is extremely important in tests made by this procedure. The temperature is measured and controlled using either a black-standard thermometer or a black-panel thermometer, which is mounted on the revolving specimen rack so that its surface is in the same relative position and subjected to the same influences as thetest specimens. C.2.2 The exposure apparatus is enclosed in an insulated cabinet to minimize the effects of any variation in rom temperature. A ventilation system provides a continuous stream of air through the test chamber and over the test specimens. The temperature of the air is automatically controlled by re-circulating warm ar from the test chamber mixed with cooler room air. It may be necessary to adjust and control the fan speed to meet both the specified black-panel temperature and the specified test chamber temperature.