NUREG-1537, Part 2 - NRC

I I ACCIDENTANALYsES
appendices for research'reactors licensed before January I, 1994, and 10 CFR
20.1001 through 20.2402 and appendices for research reactors licensed on or after
January 1, 1994). 'For research reactors licensed before Januaiy 1, 1994, the doses
that the staff has generally found acceptable for accident analysis results are less
than 5 rem whole body and 30 rem thyroid for occupationally exposed persons and
less than 0.5 rem whole body and 3 rem thyroid for members of the public. For
research reactors licensed on or after January 1, 1994,'occupational exposure is
discussed in 10 CFR 20.1201 and public exposure is discussed in 10 CFR 20.1301.
In several instances, the staff has accepted very conservative accident analysis with
results greater than the 10 CFR Part 20 dose limits discussed above.
If the facility conforms to the definition of a test reactor, the results of the accident
analysis should be compared with the criteria in 10 CFER Part 100. As discussed in
the footnotes to 10 CFR 100.11, the doses given in 10 CFR Part 100 are reference
values and are not intended to imply that the dose numbers constitute acceptable
limits for emergency doses to the public under accident conditions. Rather, they
are values that can be used in the evaluation of reactor sites with respect toF
potential reactor accidents of exceedingly low probability of occurrence and low
risk of exposure of the publicto radiation.'
For MIAs for research reactors, acceptable consequences may exceed 10 CFR
Part 20 limits. The reviewer will evaluate this on a case-by-case basis. The
applicant should discuss why the MHA is not likely to occur during the operating
life of the facility. -
Review Procedures
Information in the SAR should allow the reviewer to follow the sequence of events
in the accident scenario from initiation to a stabilized condition. The reviewer
should confirm the following:
* The credible accidents were categorized, and the most limiting accident in
each group was chosen for detailed analyses.
* The reactor was assumed to be operating normally under applicable
technical specifications before the initiating event. However, the reactor
..may be in the most limiting technical specificationcondition at the initiation
of the event.
* Instruments, controls, and automatic protective systems were assumed to
be operating normally or to be operable before the initiating event.
Maximum acceptable nonconservative instrument error may be assumed to
exist at accident initiation..
REv. 0,2/96 13-3 Smxw REVIEW PLAN
REV., O. 296 13-3 STANDARD REviEwPLAN,