Page "Fault tree analysis" Paragraph 11

Within the nuclear power industry, the U. S. Nuclear Regulatory Commission began using probabilistic risk assessment ( PRA ) methods including FTA in 1975, and significantly expanded PRA research following the 1979 incident at Three Mile Island.

This eventually led to the 1981 publication of the NRC Fault Tree Handbook NUREG – 0492, and mandatory use of PRA under the NRC's regulatory authority.