Interfacing systems LOCA V

This sequenee is caused by the break of the two double-disk valves between the primary system and the residual heat removal (RHR) system. The release of high pressure water in the low pressure pipe eauses the seals in the RHR pumps to break discharging 

During discharge of gases and vapours in the auxiliary system, a simultaneous transport of radioactive products takes place these products finally deposit on interior surfaces beeause of the continuous condensation of steam. It is estimated that the percentages released to the outside are rather small and the external consequenees are negligible. No short-term casualties result and only an increase of a fraction per ten thousand of the natural oecurrence of tumours in the surrounding zone are estimated. 

Procedures have been, moreover, studied to further mitigate the consequenees of the accident by the intervention of operators. The first is based on keeping the RHR pumps submerged by flooding their room by the use of fire-fighting hoses routed through the stairs. In this way the wash down of fission products is increased and their release is decreased. 

The second technique, even more effeetive, is based on preserving core cooling through  

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