Derivation and validation of a novel Semi Empirical Deposition Estimation Model (SEDEM)

Predictive models are necessary in order to minimize potential damages in the event of a nuclear or radiological release. For this reason, a novel model for the calculation of both wet and dry deposition from airborne radioactivity is proposed. Full derivation of the model and the estimation of uncertainty are presented, and the validity of the model is evaluated by calculating deposition based on several measured airborne activities in different countries. The results are compared with the corresponding measured deposition activities and the predictive power of the model is found to be good, i.e. calculated depositions being within the limits of measurement uncertainty. Additionally, limitations of the model and possible sources of error in the calculations are discussed. •Novel Semi Empirical Deposition Estimation Model based on probabilistic approach.•Takes into account both dry and wet deposition.•Dry deposition is found to be very susceptible to changes in the particle distribution.•Wet deposition is found to increase to the power of 0.315 of precipitation intensity, instead of increasing linearly.