Structural evolution of containment for Indian PHWRs

Present paper deals with the step by step evolution of containments for Indian PHWRs. This starts from the use of single containment with energy management system based on active components such as dousing system, to a complete double containment with passive energy management system in the form of vapour suppression pool. This evolution is based on design criteria and functional requirements as well as various research and developmental work done in different areas related to containemt design. The text initiates the discussion with the brief description of containment systems for different power reactors in India. This is followed by the design criteria and the functional requirements adopted for the containments. Identification of different areas chosen for developmental work and their influence on the design/construction of our containments are described next. It concludes with the indication of future thrust in this area. (orig./GL)