Within the IAEA program EMRAS, an exercise has been performed by 7 countries to evaluate the consequences of an acute atmospheric release of tritium (10g). This study aimed at giving practical technical information to decision-makers. Three scenarios with different meteorological conditions were modeled.

The objective of this paper is to give the main information about transfer and impact, evaluate uncertainties in models/assessments and so help to set countermeasures. From the results of this exercise, reference activity values for countermeasures can be discussed.

All pathways and chemical forms (HTO-HTOBT) are considered.