ML19309C460
| ML19309C460 | |
| Person / Time | |
|---|---|
| Issue date: | 11/05/1979 |
| From: | Bender M Advisory Committee on Reactor Safeguards |
| To: | Advisory Committee on Reactor Safeguards |
| Shared Package | |
| ML19309C446 | List: |
| References | |
| RTR-REGGD-01.097, RTR-REGGD-1.097, TASK-OS, TASK-RS-917-4 ACRS-1688, NUDOCS 8004080628 | |
| Download: ML19309C460 (3) | |
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UNITED ETATES O
NUCLEAR REGULATORY COMMISSION f
g ADVISORY COMMITTEE ON REACTOR SAltEGUARDS
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W AsMiMctoN. D. c. EeH6 e
Movember 5, 1979 h
I. Bender FRCM:
CXINEWS CN RinUIATCRY GUIDE 1.97 SUE 7ECT:
h e Regulary Guide still does not have the proper approach to accident l
f the information. W e requirements are too pervasive and the purpose o i
he 1MI-2 experience showed that a few carefully se all that was required to respond to the emergency.
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Se guide should differentiate between instrumentation needed prompt y if available the time of an accident and that which can be provided laterFor exam of primary coolant, containment, filter effluents should be permanent on a standby basis.
l installed installed but the reasuring instnanents need not be per d
h
-ident would allow ample time for such instruments to be installed once t e ac Instruments intended to show early progression oC an Fuel temperatures and outlet coolant tea-event is identified.
Core coolant voiding is anotaer.
cecident need special attention.
peratures are exemplary of this capability.Ec guide should req d tMn establish how they are to be measured.
apability It is unwise to specify accident instrumentation that has performance c b bility of unique to a specific accident unless that accident has a high pro aFor ex i
imposing the performance demands.
f settings tut it is i
to be measurable to some level above the pressure relie If bursting unnecessary to measure the pressure level up to t t rs would bursting, it not be able to respond to the event.
pressure relief valves. If we were interested in a pressure nearA mean i
i would be only because we might want to reuse the vessel.
but that is not an structural strain would be valuable in such a circumstanceThe pressure measuri instnanent to follow the course of an accident.
Ioss of in-contairunent for contairinent is an entirely different problem.
ssure over a cooling could cause overheating and consequent ight be installed sometime after the accident had been initiated.
vering the It is import, ant that this guide not become a set of requirements coS e i
an monitoring of every minor accident. help the operator in emergen l
accident on a timely basis.
.l-l b
f 3 -L 800.4080628
hvember 5, 1979 The following is a logical approach:
Establish the classes of accidents that need to be monitored with special instrianents e.g., gross fuel damage, radio-1.
acitivity release to containment, primary system rupture, MWS type reactivity excursions.
Examine the plant to determine what is normally provided as instrunentation of use in accident circumstances.
2.
Determine whether any important accident parameters c
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3.
instruments should be permanently installed.
Determine what contingent provisions are needed to allow for instument and sampling capability in the event of an accident.
4.
Determine whether provision to add instrunents in the event of an accident is appropriate and if so how?
5.
Use some type of probabilitic approach to determine how to cpalify instrumentation for this purpose (e.g. how of ten 6.
?)
is a the use of normal instrumentation to follow the course it exists. Too ment a part of this accident monitoring capability becauseWe want to specify much monitoring capability is confusing to the operator.the m ily interpretable i
i with respect to accident mitigation during emergencies.
A conscious decision needs to be made as to where to dr is specifically intended to follow the accident over a i d of time It is igortant as a basis for operational guidance and emergency response.
f the accident.
that emergency monitoring information be related to symp h w the Core outlet tagera-condition of equipnent needed during accident recovery.ture is superheated and thus the fuel is not being adequately cooled.
is no se<:endary concurrent with high coolant pressure may indicate that there Differenti-coolant or that primary coolant flow through the c diagnostic
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instrumentation, for example, core pressure drop.
d be take to In establishing the qualifications for instrumentation, care aboul i t d measuring avoid imposing requirements that result in a highly sophist ca e I
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November 5,1979
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ring device to satisfy circumstances that have low probability of occur Fbr example, cimultaneously with the type of event to be monitored.
i a fission countet that is called upon to work becaus i
cill respond to a demand at 0.2g might be a more likely requirement 8
3, and might be easily met with existing te&nology.
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