NUREG-1537, Part 2 - NRC

CHAPTER4
* materials
* compatibility with the operational environment
* structural designs
* response to radiation heating and damage
* capability to be moved and replaced, if necessary.
Nuclear characteristics should be discussed in Section 4.5 of the SARP
Acceptance Criteria
The acceptance criteria for the information on neutron moderators and reflectors
include the following:
* The non-nuclear design bases such as reflector encapsulations should be
clearly presented, and the nuclear bases should be briefly summarized.
Non-nuclear design considerations should ensure that the moderator and
reflector can provide the necessary nuclear functions.
* The design should ensure that the moderator and reflector are compatible
with their chemical, thermal, mechanical, and radiation environments. The
design specifications should include cladding, if necessary, to avoid direct
contact with water orto control the escape of gases. If cladding used to
avoid direct contact with reactor coolant should fail, the applicant should
show that the reactor can continue to be operated safely until the cladding
is repaired or replaced or should shut the reactor down until the cladding is
repaired or replaced.
* The design should allow for dimensional changes from radiation damage
and thermal expansion to avoid malfunctions of the moderator or reflector.
* The design should include experimental facilities that are an integral part of
the reflector. If the facilities malfunction, the reflector components should
neither damage other reactor core components nor prevent safe reactor
shutdown.
* The design should provide for removal and/or replacement of solid
moderator or reflector components and systems, if required by operational
considerations.
* Technical specifications, if required, should be proposed according to the
guidance in Chapter 14 of the format and content guide, which describes
important design aspects, and proposes limiting conditions for operations
and surveillance requirements. The proposed technical specifications
should be justified in this section of the SAR.
NUREG-I 537. PT 2 4-8 REV 0,2/96
NUREG I1537, PART 2 48 REV 0,2/96