Nuclear safety in the United States inadvertently reversed pipe restraints at the Diablo Canyon Power Plant reactors, compromising seismic protection systems, which further undermined confidence in nuclear safety. All of these well-publicised events, undermined public support for the U.S. nuclear industry in the 1970s and the 1980s. In 2002, the USA had what former NRC Commissioner Victor Gilinsky termed "its closest brush with disaster" since Three Mile Island's 1979 meltdown; a workman at the Davis-Besse reactor found a large rust hole in the top of the reactor pressure vessel. Recent concerns have been expressed about safety issues affecting a large part of the nuclear fleet of
Nuclear reactor safety system down a nuclear reactor during accident conditions. The ECCS allows the plant to respond to a variety of accident conditions (e.g. LOCAs) and additionally introduce redundancy so that the plant can be shut down even with one or more subsystem failures. In most plants, ECCS is composed of the following systems: The High Pressure Coolant Injection (HPCI) System consists of a pump or pumps that have sufficient pressure to inject coolant into the reactor vessel while it is pressurized. It is designed to monitor the level of coolant in the reactor vessel and automatically inject coolant when the level drops