<prompt> Bhala ukuqhubeka kwalesi sigaba - Emkhakheni wamandla enuzi, i-U.S. Nuclear Regulatory Commission yaqala ukusebenzisa izindlela ze-PRA kufaka phakathi i-FTA ngo-1975, futhi yandisa kakhulu ucwaningo lwe-PRA kulandela isigameko sango-1979 e-Three Mile Island  <response>: . futhi. Lokhu ekugcineni kwaholela ekushicilelweni kuka-1981 kwe-NRC Fault Tree Handbook NUREG0492, kanye nokusetshenziswa okuphoqelekile kwe-PRA ngaphansi kweziphathimandla zokulawula ze-NRC. 