The medicine still requires new, more advanced tools for better human body diagnoses. The great developments in electronics let to construct more and more sophisticated instruments. The system described in the paper lets to check functionality of one of human body subsystems - the breathing system. It can measure dynamic changes of temperature and dew point temperature (absolute value of humidity) of inspired and expired air in different places of human nose and throat. Some example results of dew point hygrometer and temperature measurements during respiration are presented. New factors describing condition and capability of human breathing system are described. ©2007 IEEE.