Common Concerns



Photo: NRC File Photo


Photo: NRC File Photo

The first ever incident of reactor meltdown in nuclear power history occurred at Three Mile Island Nuclear Power Plant in the USA on 28 March 1979. The accident began with a malfunction in the secondary cooling circuit. Due to misleading instrumentation, the operator made an incorrect response which finally led to a loss of reactor cooling and a partial meltdown of the fuel in the reactor. However, as the nuclear power plant had several layers of safety protection, only a small amount of radioactivity was released to the environment as a result. Residents nearby took initiatives and evacuated themselves temporarily after the incident. There was no reported case of injury or death.

After the incident, nuclear operators in the US established the Institute of Nuclear Power Operations (INPO) to improve safety practices in nuclear power plant operation and facilitate experience sharing among nuclear operators.