Ambient temperature sampling method for detection of ⁸⁵Kr in the atmosphere

The analysis of atmospheric ⁸⁵Kr is time consuming, complicated and which does not facilitate the monitoring of continuously and automatically carried out in outside. This paper tried to study a method of sampling the ⁸⁵Kr under room temperature from the air. It do not require operated under liquid nitrogen, it uses the hollow fiber membrane to carry out the per-concentration, and the separation of Kr using CMS. The proportional counter is used for the measurement of the activity of sampled ⁸⁵Kr. The recovery rate of the device, system graduation of scale and the detection limit of the method have been analyzed and discussed in this paper. The activity of ⁸⁵Kr in the air measured with developed installation is 1.09 ± 0.06 Bq/m³ (0 ℃, 0.1 MPa) in Tai Yuan district. This method can be applied to routine monitoring of ⁸⁵Kr in the atmosphere of nuclear establishments locale. (authors)