The calibration of dew point hygrometerand micro-moisture meter in ultra-lowhumidityrangewas doneby usingprecisiondew point hygrometer and low range humiditygenerator.
The presence of influenza is quite rare in the spring, summer and fall, when people don't use indoor heating as much and the humidity tends to be in the comfortable 50%-to-70% range, says Dr. Marr.