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

Abstract

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.

Appendix

$$\epsilon \left( \% \right) = \frac{NetArea}{{t \times Activity\left( {Bq} \right) \times P}}$$

(A.1)

$$\epsilon \left( \% \right) = (a + c \times \ln E + e \times \left( {\ln E} \right)\left( {\ln E} \right)^{2}) /\left( {1 + b \times \ln E + d \times \left( {\ln E} \right)^{2} } \right)$$

(A.2)

$$\epsilon \left( \% \right) = \frac{{\left( {a + cE + eE^{2} } \right)}}{{\left( {1 + bE + dE^{2} } \right)}}$$

(A.3)

$$MDA \left( {Bq} \right) = \frac{2.71 + (4.65 \times \sqrt {b}) }{t \times \epsilon \times P}$$

(A.4)