In the beginning of 2019 TVO itself detected that the collection efficiency of sampling system was not taken into account in calculation of aerosols* releases. Collection efficiency describes the sampling system’s ability to collect aerosol particles passing through stack.
Aerosol releases have been reported according to measurements, but the collection efficiency has not been taken into account in the results. Thus, the results reported earlier will be specified later, after TVO has revised the efficiency of the sampling system. The effect of aerosol releases to the calculated annual environmental dose is insignificantly small.
* Aerosols are very small particles or drops existing in gas. Some of the particles or drops can be radioactive. The amount of aerosol emissions are insignificantly small in Olkiluoto, but monitoring them is important.