TABLE OF CONTENTS Since the advent of the nuclear industry, it had been thought necessary to define a set of general safety and radiation protection criteria for nuclear plants. Indeed, although there were doubts on safety which characterized the birth of these plants, the practice of deriving the safety requirements from the indications of common cautiousness and from experience was not adopted, although this trial and error approach had been adopted for many other types of industrial undertakings and for other activities (e.g. the fire protection of buildings and plants). Instead an a-priori defined set of rules was preferred which would protect workers and the surrounding population from the consequences of hypothetical accidents. On the other hand, the realistic accident situations and their possible complications appeared from the start so numerous that an actual document of rules was necessary (in addition to research programmes on a multiplicity of different fields). [1]
[1]Simpler, yet very reassuring, methods such as the one then used for the safety demonstration of the first elevators, were inadequate.
In 1849, in New York, a new type of building was invented and subsequently commercialized. It was based on the use of prefabricated cast iron elements (columns, beams, ornaments) connected by bolts. This innovation gave origin to a new architectural style, the one based on cast iron buildings, various example of which still exist (Soho). In addition to the possibilities of prefabrication and the rapidity and economy of construction, the cast iron buildings could be much higher...
