We are presently working on problems associated with kindergartens which, with regard to indoor climate, are quite over populated. Typically, the kindergartens are around 300 m2 inarea and 700-1,000 m3 in volume, with 60-80 children, and withnatural ventilation only. The basic air change rate is 0.2-0.4 ach. As we have shown*, users have a tremendous impact on air infiltration which, in the kindergartens, rises from the basic 0.2-0.4 to 0.7-1.5 ach when the kindergarten is in use.
The paper begins by developing the concept of CONTAINMENT and describes how the ventilation system of a nuclear plant plays amajor role in the provision of this CONTAINMENT and in ensuring that the plant can be operated safely. It continues to describe the various demands that a nuclear plant places on the ventilation system and describes the types of areas that require ventilation. The paper finally describes how BNFL Engineering Division have designed a new generation of reprocessing plants for Sellafield that have low air throughputs.