ML20012G424
| ML20012G424 | |
| Person / Time | |
|---|---|
| Issue date: | 02/18/1992 |
| From: | Office of Nuclear Reactor Regulation |
| To: | |
| References | |
| HPPOS-254, NUDOCS 9303020117 | |
| Download: ML20012G424 (5) | |
Text
_ _ _ _ _ _ _ _ _ _ _ _ _ _
t
?
254 4
RECORD #254 l
l TITLE:
HEALTH PHYSICS POSITION: DEFINITION OF UNPLANNED RELEASE l
l l
l l
l l
l
~
l i
i l
254 nonno7 9303020117 920218 e'
~o L Y' v ')b l' Q,{.
y.
PDR ORO NRRB PDR jt'LD hw b(W@l l
1
J k3 ElC
'o UNITED STATES
~,,
8
(
g NUCLEAR REGULATORY COMMISSION g.k
- E WASHINGTON, D. C. 20555 i
28 (vj February 18, 1992 MEMORANDUM FOR:
James H. Joyner, Chief, EPRBP, DRSS, Region I William E.
Cline, Chief, EPRPB, DRSS, Region II L. Robert Greger, Chief, RPB, DRSS, Region III L. Joseph Callan, Director, LRSS, Region IV Gregory P.
Yuhas, Chief, EPRPB, DRSS, Region V
FROM:
LeMoine J. Cunningham, Chief Radiation Protection Branch Division of Radiation Protection and Emergency Preparedness Office of Nuclear Reactor Regulation
SUBJECT:
DEFINITION OF UNPLANNED RELEASE Our November 26, 1992 memorandum presented to you for comment the definition for the term " unplanned release" for inclusion as a Health Physics Position (HPPOS).
Comments were received from two of the Regions.
These comments have been incorporated into the HPPOS.
The changed page is shown with the former verbiage struckout and the replacement verbiage redlined.
If.there are any questions, please contact Jack Hayes (504-3167).
I
//
LeMoine J.
Cunningh m, Chief Radiation Protection Branch Division of Radiation Protection and Emergency Preparedness Office of Nuclear Reactor Regulation
Enclosure:
As stated
4 i
l I
Definition of Unplanned Release UNPLANNED RELEASE l
2 Definition:
The unintended discharge of a volume of liquid l
or airborne radioactivity to the environment.
l 1
Guidance:
An unplanned release is the unintended discharge
[
of radioactive material from a source.
Typical examples of an unplanned release are the discharge of the contents of the wrong waste gas decay tank or the wrong liquid radwaste release tank.
Another example of an unplanned release is the l
discharge of a source, e.
g.
turbine building sump, that is designed to divert its contents to the liquid radwaste system j
for processing on either the detection of activity or a l
certain level of activity and, instead of being diverted, is discharged offsite.
It should be noted that instances as described above are rare.
l j
Clarification:
It should be noted that a change in activity i
level from a release source or the release from a new or i
different source is not necessarily considered an unplanned release.
Consider the following cases.
l Case 1:
Inadvertent release of the contents of a waste d
t i
gas decay tank through the plant vent.
4 j
The release point is the same as that for other sources and although the source is new, the l
important fact is that the discharge is i
unplanned.
Therefore, the release would be j
considered an unplanned release because no discharge of any waste gas decay tank was planned.
Case 2:
Inadvertent release of the contents of the j
wrong waste gas decay tank through the plant vent.
4 t
j The release point is the same as that for all waste gas decay tanks and although the source is
- new, the important fact is that the
{
t discharge is not the intended one.
It is the 3
wrong tank.
The release was meant to be the contents of a different tank.
Therefore, the release is unplanned.
4 l
Case 3:
Leakage from various pipes and valves in the Auxiliary Building are r'eleased from the plant 3
vent via the Auxiliary Building ventilation system.
l l
l i
f 8
i s
2-t The ful. tion of the Auxiliary Building Ventilation System is to ventilate areas of the Auxiliary Building.
In the course of performing this function, it is designed to handle the leakage associated with various pipes and valves. This would not be considered an. unplanned release since the design of the system is to treat the airborne leakage associated with various pipes and valves.
Normal expected leakage would not be considered an unplanned release since the system is designed to treat routine leakage from various pipes and valves.
However, large leaks due to unexpected valvo or pipe failures that resulted in a grantity of release such that a 10 CFR 50.72 or 10 CF9 50.~i3 report is required, would be censidered an unplanned release.
B h
A '.
i r
s 9 3 The function of the Auxiliary Building Ventilation System is to ventilate areas of the Auxiliary Building.
In the cour.se of i
performing this function, it is designed to handle the leakage associated with various pipes and valves. This would not be considered an unplanned release since the design of the system is to treat the airborne leakage associated with various pipeh and valves?
leekegc.
!!as--t-he-scurce change 3?
Nc!
It 13 st4-1-1-the Icakage assoelat+d-vit4t--tim-varieue pipes and valves.
- as the--quant-ity of the i
release changed?-Possibly4-But-quent-ity plays no-rele-in-determining-whether o release is planned-or-unplenned.
The hcy concept is
-intent.
N6EshlT6kpdEtisd 31eskag e W6H1dinoti bs 1
66ns idefed i fahtunf}/N th5atyrout!ineilsakage
!!nnedVrelsaset 7sinceF the histSmfi'sfdssigned from :variousipipesiandt valvesh JEoweverf.:ilarge le aks Ldu e*tstunexp e cte'd ivalVeloripipsif a ilure s that? resultdd Vin ; al.:iquantitylof s releass Fsu6h Ehat[ajl0:1CFR' 502.72E'or[10} CFk50373Jfepbrtlis pequ ired hjould gbeyon^s id e(sd MjnMunp} anned r,e, leas.e;-
~ -a i
I r
i i
1 e
[
1