The Full Form of LPSA is Living probabilistic safety assessment.

In Probabilistic Safety Assessment (PSA) all attention is paid to analyze a system which is a time consuming effort so there is a need to develop a system network to support the analyst and to reduce manpower. To handle the physical, operational and organizational changes and to utilize the PSA information effectively the development of living Probabilistic Safety Assessment (LPSA) is essential. This paper presents a detailed methodology for LPSA. One part of this methodology is Advanced Control Room Operator Support System (ACROSS) which is helpful for updating the LPSA model. This methodology also provides help to make the control rooms in Nuclear Power Plants (NPPs) more advanced and user friendly. The study also makes recommendations for further use and development of this technique in the present and future NPPs.