Document: NUREG-0800
Document ID: 38291c4d-6d61-4922-8b44-6af61374cfaa
Document Type: srp
Title: ENGINEERED SAFETY FEATURES MATERIALS
Source: NUREG-0800
Source URL: https://www.nrc.gov/docs/ML0523/ML052340646.pdf
Revision Date: 2023-06
Chapter: 6
Section ID: 6.1.1
CFR Part: 
CFR Title: 

Content:
e for Welding Low-Alloy Steel." 11. Regulatory Guide 1.54, "Quality Assurance Requirements for Protective Coatings Applied to Water-Cooled Nuclear Power Plants." 12. Standard Review Plan Section 3.11, Appendix, "Chemical and Radiological Environment in Containment During Postulated Accidents." 13. Standard Review Plan Section 5.2.3, "Reactor Coolant Pressure Boundary Materials." 14. Standard Review Plan Section 6.2.5, "Combustible Gas Control in Containment." 15. Standard Review Plan Section 6.5.2, "Containment Spray as a Fission Product Cleanup System." 16. Standard Review Plan Section 10.3.6, "Steam and Feedwater Systems Materials." 17. Branch Technical Position MTEB 5-7, "Material Selection and Processing Guidelines for BWR Coolant Pressure Boundary Piping" (attached to SRP Section 5.2.3). 18. Branch Technical Position MTEB 6-1, "pH for Emergency Coolant Water For PWRs," attached to this SRP section. 6.1.1-12 Rev. 2 - July 1981 BRANCH TECHNICAL POSITION MTEB 6-1 pH FOR EMERGENCY COOLANT WATER FOR PWRs A. Background To establish the minimum value of pH in post-accident containment sprays in pressurized water reactors, the Chemical Engineering Branch has reviewed the available information and recommended the criteria listed in the Branch Tech- nical Position below. The minimum pH value of 7.0 follows from the Westinghouse report (Ref. 1) conclusion that, in ECCS solutions adjusted with NaOH to pH 7.0* or greater, no cracking should be observed at chloride concentrations up to 1000 ppm during the time of interest. Figure 7 of the Westinghouse report shows that the time for initiation of cracking of sensitized and nonsensitized U-bend specimens of Type 304 austenitic stainless steel in solutions of 7.0 pH having 100 ppm chloride was 7-1/2 months and 10 months, respectively. The great majority of tests reported in the Oak Ridge report, Reference 2, were performed with pH of 4.5, and only two tests were conducted with pH values other than 4.5. Some cracking was