Abstract: A simpling method is proposed to estimate the derived air concentration (DAC) of aerosols in nuclear power plants through wiping sampling. This method considers the correction of difficult to measure nuclide 63Ni and the correction of response coefficients between different areas of measuring instruments, wiping sampling paper, and high flow rate air sampling filter paper. Based on the measurement and analysis of the average half-life of radon and its daughters in the deposition part of high flow rate air sampling filter paper, a correction method for the measurement results of high flow rate air sampling is proposed. The main conclusions are as follows: (1) The proportion of representative nuclides measured by wiping samplings is relatively consistent with that measured by actual air sampling; (2) The correction of difficult to measure nuclide 63Ni has a minor impact on the overall results, ranging from 1% to 4%; (3) A typical mixed DAC ranges from 1.62×10³ Bq/m³ to 3.02×10³ Bq/m³, which has certain reference value in similar nuclear power plants; (4) A mixed DAC on air sampling filter paper for a nuclear power plant is relate to 14-66 s^-1 measured using 6150AD5+AD17 and CF-901-DIGITAL/230 under given measurement conditions; (5) The average half-life of radon and its daughters varies from 6 minutes to 12 minutes under the set sampling time and sampling flow rate. Other nuclear power plants can refer to the above mentioned methods to measure the typical mixed DAC and the typical relationship between aerosol concentration values and surface contamination values of their nuclear power plants, in order to guide high flow rate air sampling and set aerosol contamination determination thresholds.

Key words: aerosol, wiping sampling, derived air concentration, high flow rate air sampling, radon and its daughters