ML19312C754
| ML19312C754 | |
| Person / Time | |
|---|---|
| Site: | Oconee  |
| Issue date: | 08/19/1969 |
| From: | US ATOMIC ENERGY COMMISSION (AEC) |
| To: | |
| Shared Package | |
| ML19312C752 | List: |
| References | |
| NUDOCS 7912190964 | |
| Download: ML19312C754 (4) | |
Text
,
e DRS TECHNICAL SAFETY GUIDE ON
' CONTAINMENT LFM TESTING-Definitions Class A test:
Integrated leak test Class B test:
Penetrations Class C test:
Isolation Valves Class D test:
ESF for leak control Use of B&C tests serve to justify reduced - pressure A-test The guide proposes a graduated increase in the test interval for the first three Class A tests, based in part on the design leak rate and calculated peak accident pressure.
In the section under testing, further definitions are:
P:
calculated peak accident pressure P
P:
test pressure, between 0.5P and 1.0 P t
p p
L
- Leakage at P, initially p
p L
leakage at P, initially tg:
tech-spec allowabic operationa'l leak rate, measured at P L
L,:
a measured leak rate at P (re-tes t) g L:
tech spec limit for leak 0 P t
t L:
lictit for leak @ P P
P L,:
DBA-icak rate limit ~
Some' suggested requirements are:
1.
If L > L, revise retest schedule.
2*
If Lm > L, even-for 1-year test interval, then increase margin between tech-spec limit L and L Y912190p
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3.
If,'after repairs,'L
>L n
. pera e.
ass B te'sts will a
to, be performed at P.
Repair and retest. criteria are cited.
Class B test intervals should not exceed one year.
Some mathematical relationships are:
\\
fR T L
=
P P P L
'R T /
a i a a L.=fP g k pl p
to "
t( ~^
L where a represents a margin factor, a function of test' interval and classification.
The proposed tech specs specify peak accident pressure as 53.3 psig (P )
The test pressure P = 1/2 P, or 26.65 psig. Fessing from the tech specs is apecification of L,, margin at P, and a 40-year tes ting scheme.
In fact, it is not clear on the face of the tech spec that leakages are to extrapolated up to P, although measured at P.
No ' individual penetrations (valves, seals, hatches) ' leak rate is listed in the tech. specs.
Our guide. Paragraph 5.31 'has a repair and retest proviso en single-isolation valve leak rates.
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4.
L..
REACTOR BUILDING LEAK RATE CALCULATIONS FOR OCONEE 4
Oconee Tech Spec 15.4.3 (pp15-50 et. seq.) deal with RB leak rate.
They use these terms:
Lev = net equivalent leak rate in terms of iodine total leak rate L
=
T leak rate through liner and untested penetrations L
=
RB L
= leak rates through tested penetrations p
T RB +
~
pent Since L is filtered (90% efficiency for iodines) then Lev " bRB + (
- pent a
f pent) + (0.10)Lpent (L
~b or L
=
y T
L,
=L
- 0.90 L,
or T
Technical specification 15.4.3A provides :
1.
L < 0.25% by volune/24 hours T
2.
L,
< 0.275%/24 hours Section A2 permits L to be as high as 0.50%/24. hours, provided half or 0.25% goes through'RBthe penetration room.
Tech spec. 15.4.3B indicates a test schedule.
Unit 1 would have an initial full-pressure test and half-pressure before fuel loading, and another half-pressure af ter hot functional testing.
Unit 1 would be retested af ter the first refueling outage.
No further tests are scheduled; the test results would be used to determine future needs.
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e Paragraph C-1 of 15.4.3_ concerns penetration testing. Listed are
- a. Valves and' Electrical Penetration
- b. '. Ratch seals I
'c.
Fuel transfer tube seals,
d.
Isolation valves Not listed are weld test channels and angles Acceptance criteria-is in-paragraph C-2 for the penetration tests.
Comments:
It appears that the proposed tech specs would permit a leak rate of 2.75%
per day (gross, or L pr vided it all went through the penetration room.
T That is, L = 2.75%
T L
=0 g
L
= 2.75%
pent L
=LRB + 0.'10 L ev pent L,y = 0 + (0.10) (2.75) = 0.275%
This is 'S 1/2 times the leak rate assumed in the FSAR, p 14-65.
Since the noble gases are unfiltered, the whole body dose may be 10 rem instead of the 1.9 - rem mentioned.
It seems like some limit on L is indicated.
^
pent I also wonder how the charcoal heat load was calculated, if these high leak rates to the penetration room do in. fact occur.
Mention is made on p 15-53 about 2/3 down the page, of a "0.5 percent allowable 1imit at the design pressure".
I did not see that limit as a
~
tech spec._ A sentence near the top of p. 5-55 is similarly vague.
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