Influence of the migration of radioactive contaminants in soil, resident occupancy, and variability in contamination on isodose lines for typical Northern European houses.

In the remedial phase following an accidental radioactive release, it is important that soil decontamination measures are carried out on the areas that contribute most to the radiation dose. In this study, the newly developed concept of isodose lines was applied to the area around typical Swedish dwellings to identify these areas. The influence of the most common building materials in Sweden, wood and brick, and the importance of the positions of doors and windows on the isodose lines were demonstrated for specific positions inside the houses, as well as for the entire house, assuming the residents exhibit typical resident occupancy.

European decision support modelling of long-term external doses received in inhabited areas contaminated by a nuclear power plant accident - 2: Post deposition contaminant mobility on outdoor surfaces.

To enable estimation of time-integrated external doses to persons staying in an inhabited area radioactively contaminated by aerosols and gases released in connection with a large nuclear power plant accident, additional knowledge to that described in the first part of this paper is needed on the post-deposition migration of different types of contaminants on the various relevant types of environmental surface. This part of the paper describes how the migration processes are modelled dynamically in the European standard inhabited area dose model, ERMIN, and presents the newest parametric datasets. It is explained how the total information in both parts of the paper may be used to estimate doses received over time by populations in radioactively contaminated inhabited areas.

European decision support modelling of long-term external doses received in inhabited areas contaminated by a nuclear power plant accident - 1: Initial relative dose rate contributions from different contaminated outdoor surfaces.

Dose prediction tools making use of existing knowledge on the environmental behaviour of radiocontaminants are essential for justification and optimisation of recovery countermeasure strategies for contaminated inhabited areas. In this context, one necessary requirement is to estimate the relative initial contaminant distribution on different types of surfaces in the environment and the resultant initial dose rates to humans staying in the environment. This paper reports on the latest parametric refinements in this context for use in the ERMIN inhabited area dose model, which is an integral part of the European emergency management decision support systems ARGOS and RODOS.

Joint Nordic nuclear research to strengthen nuclear emergency preparedness after the Fukushima accident.

Contrary to most areas of Europe, the Nordic countries (Denmark, Finland, Iceland, Norway, Sweden, and the Faroe Islands) have for many years shared a regional research and development program on nuclear reactor safety and emergency preparedness - NKS. In spite of its project results having received great recognition and having been integrated in state-of-the-art emergency preparedness tools over the world, NKS as an organization does not seem well known outside the Nordic countries. Although the Fukushima accident had no health impact at all in Nordic areas, it taught a number of lessons of generic nature with respect to new R&D tasks that could further strengthen and secure future maintenance of the Nordic region's capability to effectively respond to such events.

Comparison of experimental and calculated shielding factors for modular buildings in a radioactive fallout scenario.

Experimentally and theoretically determined shielding factors for a common light construction dwelling type were obtained and compared. Sources of the gamma-emitting radionuclides Co and Cs were positioned around and on top of a modular building to represent homogeneous fallout. The modular building used was a standard prefabricated structure obtained from a commercial manufacturer.

Revision of deposition and weathering parameters for the ingestion dose module (ECOSYS) of the ARGOS and RODOS decision support systems.

The ECOSYS model is the ingestion dose model integrated in the ARGOS and RODOS decision support systems for nuclear emergency management. The parameters used in this model have however not been updated in recent years, where the level of knowledge on various environmental processes has increased considerably. A Nordic work group has carried out a series of evaluations of the general validity of current ECOSYS default parameters.

Effect of Nordic diets on ECOSYS model predictions of ingestion doses.

The ECOSYS model is used to estimate ingestion dose in the ARGOS and RODOS decision support systems for nuclear emergency management. It is recommended that nation-specific values for several parameters are used in the model. However, this is generally overlooked when the systems are used in practice.