Nuclear Power Safety

Introduction

Three Mile Island Nuclear Power Plant
(click image to enlarge)

On March 28, 1979 a sequence of events took place at the TMI-2 reactor at the Three Mile Island Nuclear Power Plant near Middletown, PA that resulted in the most serious accident in U.S. commercial nuclear power plant operating history. It was later determined that, due to design deficiencies, mechanical malfunction and human error, the reactor overheated and about half of the reactor core melted. Very small amounts of radiation leaked from the reactor into the surrounding areas.


The event transformed the nuclear industry and the governmental policies regulating the industry's safety standards. Sweeping changes at the Nuclear Regulatory Commission (NRC) and its policies greatly altered the safety requirements for all nuclear power plants and the design criteria that were expected for new construction.