ASME SMR ROADMAP
(STP-NU-072)
Presented at:
Nuclear Energy Standards Steering Collaborative
November 3, 2014
Richard Black
AdSTM
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SMR ROADMAP BACKGROUND AND PURPOSE
• Respond to near-term SMR licensing schedules (Design
Certification Applications to NRC 2015-16) to ensure effective
licensing
• Interact with vendors, ASME and NRC to determine
Code/standard issues
• Identify issues that may present barriers or challenges to
effective licensing
• Provide recommendations and strategies to address potential
ASME issues
• Provide a framework to address other nuclear standard issues
for SMRs
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ROADMAP SCOPE
• U.S. SMR designs scheduled for near-term licensing reviews
(Submittals: 2015-2016) and commercial deployment (20222025)
• Only U.S. LWR SMR designs
– Non-LWR SMR designs considered either not ready for licensing or
ready for commercial market
– Roadmap was limited to currently proposed U.S. LWR designs
• Roadmap might be revised in the future to address
Code/Standard issues for other designs
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Roadmap Interactions
• Domestic SMR vendors
• ASME Code Committees
• NRC and other stakeholders
– NRC Public Meeting and Conference Call: 2/8/14
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ASME Nuclear Code Considerations
10 CFR 50.55(a) Requirements:
• “Reactor Coolant Pressure Boundary” for Class 1 components of
Section III, “Rules for Construction of Nuclear Power Plant
Components,” of the ASME Boiler and Pressure Vessel Code,
Subsection NB
• “Quality Group B ” for Class 2 components Section III, Subsection
NC
• “Quality Group C” for Class 3 components Section III, Subsection ND
• “Inservice Testing Requirements” for Class 1, 2, and 3 components
of the ASME Code for Operation and Maintenance of Nuclear
Power Plants (OM Code)
• “Inservice Inspection Requirements” for Class 1, 2, 3, MC (metal
containment), and CC (concrete containment) components Section
XI, “Rules for Inservice Inspection of Nuclear Power Plant
Components”
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ASME NUCLEAR CODE CASES
NRC Regulatory Guides for 10 CFR 50.55(a):
• Regulatory Guide 1.84, “Design, Fabrication, and
Materials Code Case Acceptability, ASME Section III”
• Regulatory Guide 1.147, “Inservice Inspection Code
Case Acceptability, ASME Section XI, Division 1”
• Regulatory Guide 1.192, “Operation and
Maintenance Code Case Acceptability, ASME OM
Code”
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ROADMAP FINDINGS – CODE SECTION III
• Vendors have initiated discussions with Code Committees and NRC
regarding potential issues
• Section III: Vendors believe SMR designs comply with requirements
• NRC could decide that certain Section III Code exceptions based on
small size are not acceptable for certain unique aspects and safety
functions of SMR designs, e.g.:
– Exemption for impact testing of small pipes and fittings
– Exemption for reactor coolant pressure boundary components whose
break results in leakage within the capacity of the normal makeup system
from meeting the requirements of Subsection NB (Class 1)
ROADMAP FINDINGS – SECTION XI (InService
Inspection (ISI))
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Potential Issues
ISI exemptions for certain Class 1 small components
ISI accessibility of NuScale reactor vessel with compact
design
IWE requirements for NuScale stainless clad steel
containment not applicable – visual vs. ultrasound
examinations
Interior examination of reactor vessels and
containment in iPWR design
ISI interval requirements based on a 4-year fuel cycle
– (Code Cases initiated will resolve this issue)
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ROADMAP FINDINGS – OM CODE
• Periodic testing requirements of NuScale ECCS
valves that open to establish a natural
circulation path to provide core cooling may
require consideration by OM Committee
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ROADMAP FINDINGS FOR SDOs
• SMRs are a global enterprise with potential for
world-wide fleet deployment
• Effective licensing and deployment will benefit
from international nuclear standards
• World-wide standards can be adopted by vendor
and country of licensing origin and by country of
deployment
• International collaboration on nuclear standards
is an important safety and economic function
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