Design-basis events

The Pickering risk is estimated to be 2E-4 Sv/y to an individual at the site boundary and about 4L-.i person-Sv/y to the surrounding population. Both of which are less than DPSE in spite of age of station, the higher demographics, and the inclusion of beyond design basis events. The mean site economic risk was estimated to be 1.5 M /reactor-y,... 

One should keep in mind that every building has some level of blast resistance and the term is not synonymous with a bunker design. Blast resistant construction is sometimes referred to as blast proof." This is a misnomer since it is not realistic to provide an absolute level of blast protection. In other words, there is always some probability that a design basis event can be exceeded. 

Top-Level Regulatory Criteria Anticipated Operational Occurrences Design Basis Events Emergency Planning Basis Events... 

The SRDCs provide limiting design conditions for "safety-related" systems, structures, and. components (SSCs) and, as such, are included in the plant duty cycle. These conditions are used to ensure that the "safety-related" SSCs can be depended upon to respond to the design basis events (DBEs) to meet the dose limits of lOCFRlOO. Although the "safety related" design conditions (SRDCs) have been developed strictly as a licensing tool, they are included in the plant duty cycle to ensure that the "safety-related" SSCs can withstand the operating environment. 

Graphite Core Component Allowable Stress Limits Anticipated Operational Occurrence Performance Design Basis Event Performance "Safety-Related" Design Condition Performance Interfaces... 

The RCSS shall be designed to limit incremental radionuclides release from the core during short-term design basis events, such as steam ingress, with direct release to the environment ... 

The effects of the 11 postulated design basis events (DBEs) on the reactor core are discussed in the following. The effects of these events on fuel integrity are discussed in Chapter 15 which shows that the fuel integrity is... 

The control assemblies shall incorporate features which ensure that the control rods and reserve shutdown material enter their designated channels for all reactor configurations resulting from anticipated operational occurrences (AOOs) and design basis events (DBEs). 

Eleven design basis events (DBEs) are described in Chapter 15. imposed on the reactor internals are described below. 

The evaluation above constitutes the flood screening analysis for the HCF, which defines the HCF as a flood-dry site. Flooding is not a design basis event for the HCF. 

The consequences of these events are no more serious than the design-basis events evaluated in Chapter 3. 

The purpose of the plant dynamics study is to determine power, flow, temperature and pressure transients under various design basis events (DBE). These parameters are essential for deciding on the requirement of NRV, flow halving time and for arriving at reactor shutdown parameters along with the corresponding threshold values. The evaluation of temperature, pressure and flow are the input to the structural integrity assessment. 

Gonceptual design report has been prepared except chapters on I G, plant layout and civil structures. Various plant design data viz. plant life, design basis events, safety classification, seismic categorisation, applicable design and construction codes, computer codes, material data and site data have been compiled. 

B. No single active failure prevents at least one complete train of the SCS from being brought on line from the control room, whether this is during normal plant cooldown or following a Design Basis Event (DBE). 

Design Basis Events, their fi-equencies and acceptance limits during such events have been compiled. 

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