Как выбрать гостиницу для кошек
14 декабря, 2021
Сегодня каждый, кто собирается в отпуск и не знает, с кем оставить своего котика или кошку, может во[...]
Event Classification
It now remains to put accidents to the plant in their respective probability ranges. Table 3.4 gives a prospective listing of accidents, but this list is by no means final for any given plant, each system having to be considered on its own merits. Such a list is prepared on the basis of engineering judgment, although in the future it is expected that a qualitative classification will be defensible.
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TABLE 3.4 Classification of Events by Likelihood |
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Likelihood class |
Event |
Operational occurrences Reactivity control withdrawal error at power or start-up Random fuel failures
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Unlikely faults |
Human error Flow control error Loss of one pump flow due to loss of electrical supply Small seismic shock Feedwater heating supply failure Turbine stop-valve closure Loss of cover gas pressure Steam generator tube failure Offsite power failure Loss of onsite auxiliary power Failure of control rod hold-down mechanism Operating basis earthquake Pump mechanical failure Small pipe leaks Large bubbles reaching the core Loss of primary scram following an operational occurrence Independent active component failure following an operational occurence (see Section 3.3.4) |
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Unexpected faults |
Large system ruptures Large sodium fire Failure of core support allowing core movement Design basis earthquake Very large bubbles reaching the core Passive component failure following an operational occurrence (see Section 3.3.4) Loss of scram following an operational or unlikely fault Loss of offsite and onsite power supplies |
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Incredible faults |
A refueling accident leading to criticality Rod ejection Sudden local subassembly blockage |