ML19221B107
| ML19221B107 | |
| Person / Time | |
|---|---|
| Issue date: | 03/31/1979 |
| From: | Office of Nuclear Reactor Regulation |
| To: | |
| References | |
| NUREG-75-087, NUREG-75-087-12.2, NUREG-75-87, NUREG-75-87 12.2, SRP-12.02, SRP-SRP-12.02, NUDOCS 7907120435 | |
| Download: ML19221B107 (4) | |
Text
NUREG-75/087 fpaacg%
e-o yi,1 O U.S. NUCLEAR REGULATORY COMMISSION I-o Wii /!
STANDARD REVIEW PLAN
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OFFICE OF NUCLEAR REACTOR REGULATION LECTICN 12.2 RADIATION SOURCES RE VIEW REMMSIBIt ITIES Priury - P3diological Asser rent Branch 'RAB) t Secondary - E f fluent Trectment Systers Sranch (ETSB) 1.
< AS UF REVIEW The f ollowing "eas of tre applicant's safety analysis report (SAnj relating to radiaticn sources are rosimed as related to in-plant raJiation protection:
1.
CONTAINFD _L'?CF5 Tre descriptico of the sources of radiation that are the b sis for the radiation pro-tection 'rogra!, as used in the shield design a olaticns (SAR Chapter 11 contains the description fo: sources contained in equipr ent of the radioactive waste managec ent systems). This should include isotcpic composition, location in the plant, source strength ar.d source geor.etry, ara the basis for the values (preliminary safety analysis report (P3AR), and update in tne final safety analysis report (FSAR). Tho descriptions should include any required byproduct, source, and special nuclear raterials.
2.
AIRCW RADICACTIVE PATERJ AL MRf ES The description of the sources of airborne radioacti se material considered in the design of the ventilation syste s, as used for design of personnel protective reasures and for dose assesscent. (SAR Chapter 11 contains the description for airborne saurces that h3ve to be considered for their contributicn to the plant effluent releases, through equipment of the radioactive waste ra"agement systens or the,lant ventilaticn syster.) The descriptions should include a tabulation of the calculated concentration of radioacti se material by nuclides expected du-ing norral operation ar.d anticipcted l
operational occurrences for ewipr ent cubicles, corridors, and operatirig areas norrally occupied by operating personnel and thculd include rodels and para eters for the calca!)tions (pSAR and update in FSAR).
i In the esent of r.ew and unused designs, ETSB will, on reques t, assist Pf3 in reviewing the sources and source tern design bases.
I II.
ACCEPTANCE CRITERIA Specific acceptance criteria for these dreas of review are as follows:
l USNRC STANDARD REVIEW PLAN Svenderd review piene are preoered for the goldence of the Office of Nucteer Reactor Reguistion seeff respor's,ble for the rew ow of erphcetions to construct and operate voucleet power p ente These documento are made evedeble to the pubbe es poet of the Cormene.non a policy to enform the riurtear mdustry and the gocersi pubhc of tegu: story procedures and pohcies Stenderd review p#ene are not subststuees for requietory guides or the Commession o regWet+one end comphence weth them no not requered The steederd review plan esctiorie are keyed to Revtseon 2 of the Stenderd Format and Cuatem of Safet; Anotyese Reporte for Nucteer Power Plants Not eli sectioas of the Stenderd Format have e correspondin g remew plan Pubhehoe etsaderd review piene wdl be revesed periodecolly. as appropriate to acc ommodeve commente and to refleut new mformation and espeveence Commente ead suggeetions f oe emprovement well be concedered and should be sent to the U S Nuclear Requietory Commession Office of Nucteer Reactor Regusation Weemington. D C Nheb dev. 1 i
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All sources of radiation that necessitate designed shielding, special ventilaticq designs, special storage locations and conditions, traffic or access control considerations, special plars and procedures, r:cnitoring equiprent, etc., shall be described to the degree needed for the shielding codes used in the design process, for establishing ralated facility design features, f or plans and procedJres deVelopTent, for assessment of occupational radiation exposures, and for equipment specifications. For contained sources, the description should include plan scale drawings of each floor of the piant on which all the sources of signifi-cance are shown and identified in a r anner that can te easily related to tables containing the pertinent and necessary quantitative source para"'eters.
Their position should be accurately indicated, as well as the approximate size and shape. Airborne sources that are createJ by leakage, by opening formerly closed containers, by storage of leaking fuel ele-rents, etc., shall be identified by lcration and tagnitude, in a ranner useful for designing appropriate ventilation syster,s and in specifying appropriate r:onitoring syster:s. The assumptions r ado in arriving at quantitative values for these various sources should be specified, either in this section or by reference to Chapter il of the SM.
l Shielding and ventilation design fissicn product source terr.s will be acceptable if developed using these bases:
(1) an offgas rate of 100,000 ; Ci/sec af ter 30 minutes delay for BWRs.
l (2) C.25 f uel cladding defects for PWRs.
Coolant and corrosion activation products so'Jrce terrs should be based on applicable reactor c;)erating experience. The buildup of activated corrosion products in varicus cor:- l ponents and systers should be nuantified, Any allowar.ces rade in design source terms for such buildups should be explained. Neutron and prcept gwa source terms should be based on reactor core physics calculations and applicable reactor cperating experience.
The tables of quantitative source para ~eters, v.hich can be placed in Chapter 12 or referenceJ to Chapter 11, will be acceptable if the accorpanying text either in this section or rther referenced sections rekes it clear hcw the values are used in a shield design calculation or in a ventilation system design. In addition, the quantities will be acceptable if the reviewer can ccofirn specific values given in the tables fron the assu~ptions given along With corron tables of nuClide decay sCher es, gama ray energies, etc. ANSI N237 and Regulatory Guide 1.112 will be used for acceptance of coolant and corrosion activation products source terrs. These documents provide guidance on estimatino e f fl uent source terns. The fuel cladding cefect (of fgas rate for BWRs), which forr:s the hisis of the calculation of ef fluent fission product source ierns, is a lower value in these documents, than the 0.25- (100,000 Ci/sec for EWRs) which should be useJ as the shielding source terms as presented acove.
For byproduct, source, and special nuclear materials,10 CFR Parts 30, 40 and 70 can be used as guidance.
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i72 Rev. 1 12.2-2
III. REVIEW PROCEDURES The reviewer detemines whether the source tem design bases are consistent with the accep-tance criteria. Then, the revirwer detemines whether source strengths, concentrations of airborne radioactivity, anJ quantitative source descriptions are consistent with the assurp-tions r.ade and the nethods used by the applicant. Locations of the contained sources I
relative to shield walls, occupied areas, traf fic pathways, in-service inspection points, sampling stat lcns, controls, etc., are exmiined for any potential probler s in assuring that occupational radiation exposures (ORE) will be as low as is reasonably achievable (ALARA).
Based on the review, PAB nay request additional 'nformation or request the applicant to reevaluate his analysis for the purp0se of nodifying thoso areas which do not reet the acce;)tance cri teria given in Subsection IT.
IV.
EVALUATION FI.DIi;GS The staf f's review shouid verify that adequate and sufficient information is contained in the SAR and anendnents to arrive at conclusions of the following type, which are to be included in the staff's Safety Evaluation Report. The report will include a sumary of the applicant's coverage, the staff's basis foa review and acceptance criteria, and the findings of the revicw. The following is a brief representation of the evaluation findings.
This section contains a description of the sources of contained and airborne radioactivity used as inputs for the dose assessuent and for the shielding and ventilation designs Also inclu d ar e the assumptions ade by the applicant in 2rriving at quantitative values for these contained and airborne source terms Inside the containment during power operation, the greatest potential for personnel dose during operation is due to nitrogen-16, noble gases, and neutrens. Outside the containment and af ter shutdown inside the containnent the prinary sources of personnel exposure are fission products ' rom fuel clad defects, and activation products, including activated corrosion products. Almost all of the airborne radioactivity within the plant is due to equipnent leakage. The fission product source tems are based on 0.25 fuel cladJing defects (FWRs). The coolant and corrosion activation product source tems are based on operating experience from reactors of similar design; allcwances are included for the buildup of activated corrosion products. Tieutron and prompt gaTa source tems are based on reactor core physics 71culations and operating experience from reactors of similar design. Othcr paramettrs used, as well as a complete description of source term development, are contained in Chapter 11 The source tems presented are corparable to estimates by other applicants with similar designs and are acceptable.
The applicant has provided a tabulatic, of the raximum expected radioactive airborne concentrations in cquipnent cubicles, corridars, and operating areas, due to equiprent leakage. The bases for these leakage calculations are in accordance with Ref. 5.
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i The ventilation system will be designed to provide (nuober) volume ch3nges per hour ii, occupied areas which nay contain significant airborne activity. Air will be routed from areas of low potential airborne contamination to areas of increasing potential airborne contamination. The resulting esticated airborne radioactivity concentrations in frequently 12.2-3 Rev. i
occuoied areas will be a small fraction of 10 CFR Part 20 limits and are acceptable. The source terms used to develop these airborne concentration values are comparable to est: mates by other applicants with similar designs and are acceptable.
V.
REFERENCES 1.
10 CFR Part 70, "Special Nuclear Material."
2.
10 CFR Part 40, " Source Material."
3.
10 CF'i Part 30, " Byproduct Material."
4.
M!SI ti237, Final Draf t by Work ing Group 18.1, " Source Tern Specification," American National Standards Institute.
5.
Regulatory Guide 1.112, " Calculation of Releases of Radioactive Materials in Gaseous ar,d Liquid Effluents from i.ght-Water-Cooled Power Reactors."
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