Document: NUREG-0800
Document ID: c9c204f0-a162-491c-8c25-ee0418212f29
Document Type: srp
Title: PRESSURE-TEMPERATURE LIMITS, UPPER-SHELF ENERGY, AND PRESSURIZED
Source: NUREG-0800
Source URL: https://www.nrc.gov/docs/ML0703/ML070380185.pdf
Revision Date: 2023-06
Chapter: 5
Section ID: 5.3.2
CFR Part: 
CFR Title: 

Content:
gross failure of the RCPB that could cause a loss of reactor coolant inventory and a reduction in the capability to confine fission products. 3. GDC 31 establishes that the RCPB must be designed with sufficient margin to ensure that when stressed under operating, maintenance, testing, and postulated accident conditions, the boundary behaves in a nonbrittle manner and the probability of rapidly propagating fracture is minimized. The design must reflect consideration of service temperatures and other conditions of the boundary material and the uncertainties in determining material properties; the effects of irradiation on material properties; residual, steady-state, and transient stresses; and the size of flaws. The RCPB provides a fission product barrier, confinement of reactor coolant, and flowpaths to facilitate core cooling. Regulatory Guide 1.99 provides methods for predicting irradiation effects on fracture toughness properties that are applicable to compliance with the requirements of GDC 31. Application of GDC 31 ensures that the P-T limits for the RCPB are appropriately determined and provide sufficient margin to account for uncertainties associated with flaws and the effects of service and operating conditions, and thereby provide a minimum probability of brittle material behavior leading to rapidly propagating failure. The probability of substantial reduction in the capability to contain reactor coolant inventory, reduction in the capability to confine fission products, and interference with core cooling is thereby minimized. 4. 10 CFR 50.60 requires that all light-water nuclear power reactors meet the fracture toughness requirements, including P-T limits, as set forth in Appendix G to 10 CFR Part 50. Compliance with the requirements of this rule and Appendix G provides assurance regarding the structural integrity of the RCPB and, specifically, the reactor vessel. The next item discusses the technical rationale for this rule. 5.3.2-8 Revision 2 - March