Design provisions related to fire control in the Alto Lazio nuclear power plant

The licensing activities at the Alto Lazio nuclear power plant included systematic revision of the fire control provisions and definition of several technical aspects related to specific design. The design of the plant was reviewed according to the Italian laws for nuclear installations in order to issue a construction permit and subsequently to allow the construction or installation of each building or system. Since the first stage of the review (construction permit and licences for civil work), special attention has been given to: analysis of fire risk, definition of fire areas and selection of materials. Specifically oriented criteria were defined in order to provide effective tools for decision making as well as adequate fire prevention and passive fire protection. Some problems that arise in applying the most recent standards were caused by limitations in the conceptual design and general layout that were already 'frozen' in the earliest stages. During the successive licensing activities, e.g. licences for system installation, it was necessary to hold further discussions on aspects such as: the extent of seismic qualification of the detection and extinguishing systems; centralized and local fire supervision; the role of smoke control and ventilation systems in fire fighting; plant control requirements in the event of control room unavailability; physical separation of equipment inside the primary containment; and the required reliability of extinguishing systems, including those features necessary to ensure manual recovery of the systems. (author). 1 fig., 1 tab