Design of the ventilation system of the nuclear facility(I). General requirements

To assure that the operation of the nuclear ventilation system is effective and economic, the reasonable design of system is essential. As the nuclear ventilation system has to meet the particular conditions; to keep the rooms at an below atmospheric pressure at all times and, furthermore, to maintain frequent air circulation in the rooms, the system needs the big rotating machinery. Consequently, the construction cost and the operational cost of the ventilation system is very high. For maximum function with the minimum cost, areas are to be divided into several zones depending on the level of radioactivity and the once-through air flow in the shortest route should be adopted. The pressure difference between the zones and the number of air circulations per unit time in the rooms must be reasonable, thus, the venting air volume should be of minimum. (author). 19 refs., 7 tabs., 21 figs