Critical assessment of the monitoring sampling lines for aerosols emitted from the WWER type reactor units at the Kozloduy NPP

The assessment of the radioactive burden of the environment in the vicinity of a nuclear facility is closely connected to the correct results from the monitoring of the radio aerosol emissions, respectively to the correct sampling. In the international regulative documents are introduces few criteria for the cross section, velocity and sampling conditions using a single sampling sucker, which is the case for WWER-440 units in Kozloduy NPP. A theoretical estimation was made of possible sampling uncertainties in main ventilation channels of WWER-440 units. The probable values of total uncertainty of the results from monitoring due to sampling and transport of the samples to the 'Kalina' radiometers were calculated. (authors)