A proposal to design a new high volume standard air filter for efficiency calibration of HPGe detector

A prototype of a standard high volume air filter was proposed and constructed by a novel method, which provides a symmetric distribution of radionuclides for accurate measurements of radioactivity in air samples. Then air samples were collected at an air flow rate of 300 m3 h−1 to 900 m3 h−1 samplers for 24 h per sample. The average concentrations of 7Be and 210Pb were measured as 3.80 ± 0.46 mBq m−3 and 0.92 ± 0.33 mBq m−3, respectively. The data can be used as a basis for related measurements in the atmospheric pollution research in Iran.