Content of ²¹⁰Po in Blank Aerosol Sampling Membrane and Its Influence on Sample Analysis

In this paper, four kinds of aerosol sampling membranes made of different materials with two kinds of commonly used size specifications were analyzed, and the contents of ²¹⁰Po were given. The results show that the contents of ²¹⁰Po in domestic glass fiber membrane and polypropylene membrane are higher, and the two sampling membranes are the most widely used in daily monitoring. By measuring the uranium content in the glass fiber membrane, it is known that the high content of ²¹⁰Po is caused by the raw material for producing the membrane. The influences of blank sampling membrane on the determination of actual aerosol samples were quantitatively analyzed by actual sample determination and relative synthesis standard uncertainty estimation. The ratios of ²¹⁰Po content in the single sampling membrane of the glass fiber membranes A and B (produced by domestic A and B manufacturers) and polypropylene membrane A (produced by domestic A manufacturers) to that in the aerosol samples are higher. The influence of the determination results cannot be ignored. Therefore, it is recommended to deduct the ²¹⁰Po content in the blank sampling membrane when analyzing aerosol samples with ²¹⁰Po content greater than 30 mBq. When the ²¹⁰Po content in the aerosol is as low as tens of μBq/m³, the uncertainty of the measurement result is large after subtracting the blank sampling membrane, and a sampling membrane with a low content of ²¹⁰Po (such as quartz fiber material) should be selected.