Airflow measuring products help buildings meet the minimum outdoor air requirements of ASHRAE Standard 62.1 or California Title 24 by providing accurate monitoring and control of outside air.
Differential pressure based airflow measuring products use an array of air pressure pick-ups to compare the total pressure going through the airflow station with the static pressure in the station.
Thermal dispersion technology utilizes an array of thermal dispersion nodes positioned across the face of a duct or opening. Each node contains a pair of precision matched thermistors. One thermistor measures the ambient air temperature and the other is heated to a preset temperature differential above ambient. Each node measures air velocity. These use the known relationship between heat transfer and air velocity along with measuring power consumption needed to maintain the fixed temperature difference between the thermistors.