Emergency Systems Survivability Analysis (ESSA) is the systematic assessment process to identify all key emergency systems of the major accident events and ensure that the systems are suitable, survivable, and safe for sufficient time to perform the design functions. An ESSA includes identifying the major accident events; defining the system’s survivability requirement, and estimating the probability of the emergency system failing to perform its safety function due to the effects of the major accident events.
Reference Definition by Petrorisk.com: The objective of the ESSA is to identify those systems that are essential for the preservation of human life following any major accidental event and necessary to maintain life support on the installation. ESSA shall systematically assess the capability of the identified emergency systems to operate as intended during emergency conditions, i.e. fire, toxic gas release, explosion, etc. Findings of QRA and other safety studies, to be carried out as part of the present project scope, shall be utilized in the assessment.
Related Definitions in the Project: The HSE Management; Process Safety Engineering
