Prior to the March 1979 events at Three Mile Island, it was thought that the danger of a nuclear meltdown was almost negligible. Though there were safety systems in place, none of them would have prevented a complete catastrophe. Since the accident, the American Nuclear Regulatory Commission (NRC) and utility companies have worked together to resolve the problems that were revealed. Among the efforts and requirements put into place were: more stringent licensing procedures for operators; better training of plant operators in the event of an emergency; wider sharing of information on emergency management systems; effort to locate new plants outside of densely populated areas; more rigid quality assurance standards at all plants; strict implementation of the standards, which are subject to review by the NRC; and emergency evacuation plans that must be approved by the Federal Emergency Management Agency (FEMA). Even with these improvements to safety programs, the accident at Chernobyl in 1986 again produced worldwide concern over the hazards of nuclear power.