{"abstract":"The Nuclear Regulatory Commission (NRC) is amending its regulations to provide alternate fracture toughness requirements for protection against pressurized thermal shock (PTS) events for pressurized water reactor (PWR) pressure vessels. This final rule provides alternate PTS requirements based on updated analysis methods. This action is desirable because the existing requirements are based on unnecessarily conservative probabilistic fracture mechanics analyses. This action reduces regulatory burden for those PWR licensees who expect to exceed the existing requirements before the expiration of their licenses, while maintaining adequate safety, and may choose to comply with the final rule as an alternative to complying with the existing requirements.","action":"Final rule.","agencies":[{"raw_name":"NUCLEAR REGULATORY COMMISSION","name":"Nuclear Regulatory Commission","id":383,"url":"https://www.federalregister.gov/agencies/nuclear-regulatory-commission","json_url":"https://www.federalregister.gov/api/v1/agencies/383","parent_id":null,"slug":"nuclear-regulatory-commission"}],"body_html_url":"https://www.federalregister.gov/documents/full_text/html/2010/01/04/E9-31146.html","cfr_references":[{"chapter":null,"citation_url":null,"part":50,"title":10}],"citation":"75 FR 13","comment_url":null,"comments_close_on":null,"correction_of":null,"corrections":[],"dates":"Effective Date: February 3, 2010.","disposition_notes":null,"docket_ids":["NRC-2007-0008"],"dockets":[],"document_number":"E9-31146","effective_on":"2010-02-03","end_page":29,"executive_order_notes":null,"executive_order_number":null,"full_text_xml_url":"https://www.federalregister.gov/documents/full_text/xml/2010/01/04/E9-31146.xml","html_url":"https://www.federalregister.gov/documents/2010/01/04/E9-31146/alternate-fracture-toughness-requirements-for-protection-against-pressurized-thermal-shock-events","images":{"ER04JA10.100":{"large":"https://img.federalregister.gov/ER04JA10.100/ER04JA10.100_large.png","medium":"https://img.federalregister.gov/ER04JA10.100/ER04JA10.100_medium.png","original_size":"https://img.federalregister.gov/ER04JA10.100/ER04JA10.100_original_size.png"},"ER04JA10.098":{"large":"https://img.federalregister.gov/ER04JA10.098/ER04JA10.098_large.png","medium":"https://img.federalregister.gov/ER04JA10.098/ER04JA10.098_medium.png","original_size":"https://img.federalregister.gov/ER04JA10.098/ER04JA10.098_original_size.png"},"ER04JA10.099":{"large":"https://img.federalregister.gov/ER04JA10.099/ER04JA10.099_large.png","medium":"https://img.federalregister.gov/ER04JA10.099/ER04JA10.099_medium.png","original_size":"https://img.federalregister.gov/ER04JA10.099/ER04JA10.099_original_size.png"}},"images_metadata":{"ER04JA10.100":{"large":{"identifier":"ER04JA10.100","content_type":"image/png","size":1347,"width":213,"sha":"0a071b4baed6c578a9b1268d532de6a0","url":"https://img.federalregister.gov/ER04JA10.100/ER04JA10.100_large.png","height":66},"medium":{"identifier":"ER04JA10.100","content_type":"image/png","size":523,"width":100,"sha":"06b4ef8f9a1fb79eb93ac3255ca775fa","url":"https://img.federalregister.gov/ER04JA10.100/ER04JA10.100_medium.png","height":31},"original_size":{"identifier":"ER04JA10.100","content_type":"image/png","size":381,"width":91,"sha":"c7bf390c3ed120ca608458282ab558db","url":"https://img.federalregister.gov/ER04JA10.100/ER04JA10.100_original_size.png","height":28}},"ER04JA10.098":{"large":{"identifier":"ER04JA10.098","content_type":"image/png","size":1184,"width":128,"sha":"2719b5012c34c1326774761eb234e6b6","url":"https://img.federalregister.gov/ER04JA10.098/ER04JA10.098_large.png","height":77},"medium":{"identifier":"ER04JA10.098","content_type":"image/png","size":462,"width":61,"sha":"d9ea57c13b1eb5e43e93765c13ec89eb","url":"https://img.federalregister.gov/ER04JA10.098/ER04JA10.098_medium.png","height":37},"original_size":{"identifier":"ER04JA10.098","content_type":"image/png","size":348,"width":55,"sha":"38168c23465b578c1a46c6318d85602d","url":"https://img.federalregister.gov/ER04JA10.098/ER04JA10.098_original_size.png","height":33}},"ER04JA10.099":{"large":{"identifier":"ER04JA10.099","content_type":"image/png","size":1939,"width":292,"sha":"b2798d12a35809213eaaf4790672266a","url":"https://img.federalregister.gov/ER04JA10.099/ER04JA10.099_large.png","height":70},"medium":{"identifier":"ER04JA10.099","content_type":"image/png","size":771,"width":138,"sha":"dd5776ae648324d54b33e8eb0d8968a2","url":"https://img.federalregister.gov/ER04JA10.099/ER04JA10.099_medium.png","height":33},"original_size":{"identifier":"ER04JA10.099","content_type":"image/png","size":541,"width":125,"sha":"3cd302a36b9c78f8aca771012edd2911","url":"https://img.federalregister.gov/ER04JA10.099/ER04JA10.099_original_size.png","height":30}}},"json_url":"https://www.federalregister.gov/api/v1/documents/E9-31146?publication_date=2010-01-04","mods_url":"https://www.govinfo.gov/metadata/granule/FR-2010-01-04/E9-31146/mods.xml","not_received_for_publication":null,"page_length":17,"page_views":{"count":707,"last_updated":"2026-08-24 20:15:14 -0400"},"pdf_url":"https://www.govinfo.gov/content/pkg/FR-2010-01-04/pdf/E9-31146.pdf","presidential_document_number":null,"proclamation_number":null,"public_inspection_pdf_url":null,"publication_date":"2010-01-04","raw_text_url":"https://www.federalregister.gov/documents/full_text/text/2010/01/04/E9-31146.txt","regulation_id_number_info":{"3150-AI01":{"issue":"201004","html_url":"https://www.federalregister.gov/regulations/3150-AI01/alternate-fracture-toughness-requirements-for-protection-against-pressurized-thermal-shock-events-nr","title":"Alternate Fracture Toughness Requirements for Protection Against Pressurized Thermal Shock Events [NRC-2007-0008]","xml_url":"http://www.reginfo.gov/public/do/eAgendaViewRule?pubId=201004&RIN=3150-AI01&operation=OPERATION_EXPORT_XML","priority_category":"Substantive, Nonsignificant"}},"regulation_id_numbers":["3150-AI01"],"regulations_dot_gov_info":{"supporting_documents":[{"title":"Final OMB Supporting Statement Related to Final Rule on Alternate Fracture Toughness Requirements for Protection Against Pressurized Thermal Shock Events","document_id":"NRC-2007-0008-0019"},{"title":"Summary and Analysis of Public Comments Related to the Alternate Fracture Toughness Requirements for Protection Against Pressurized Thermal Shock Events","document_id":"NRC-2007-0008-0018"},{"title":"Final Regulatory Analysis Related to Alternate Fracture Toughness Requirements for Protection Against Pressurized Thermal Shock Events","document_id":"NRC-2007-0008-0017"},{"title":"Regulatory History Related to Supplemental Proposed Rule:  Alternate Fracture Toughness Requirements for Protection Against Pressurized Thermal Shock Events","document_id":"NRC-2007-0008-0016"},{"title":"Draft OMB Supporting Statement for Supplemental Proposed Rule","document_id":"NRC-2007-0008-0009"},{"title":"Regulatory Analysis for the Supplemental Proposed Rule to Amend Alternate Fracture Toughness Requirements for Protection Against Pressurized Thermal Shock Events","document_id":"NRC-2007-0008-0008"}],"regulatory_plan":{"html_url":"https://www.federalregister.gov/regulations/3150-AI01/alternate-fracture-toughness-requirements-for-protection-against-pressurized-thermal-shock-events-nr","title":"Alternate Fracture Toughness Requirements for Protection Against Pressurized Thermal Shock Events [NRC-2007-0008]"},"comments_url":"https://www.regulations.gov/docketBrowser?rpp=50&so=DESC&sb=postedDate&po=0&dct=PS&D=NRC-2007-0008","supporting_documents_count":6,"docket_id":"NRC-2007-0008","regulation_id_number":"3150-AI01","title":"Alternate Fracture Toughness Requirements for Protection Against Pressurized Thermal Shock Events"},"regulations_dot_gov_url":null,"significant":false,"signing_date":null,"start_page":13,"subtype":null,"title":"Alternate Fracture Toughness Requirements for Protection Against Pressurized Thermal Shock Events","toc_doc":"Alternate Fracture Toughness Requirements for Protection Against Pressurized Thermal Shock Events","toc_subject":null,"topics":["Antitrust","Classified information","Intergovernmental relations","Nuclear power plants and reactors","Radiation protection","Reporting and recordkeeping requirements"],"type":"Rule","volume":75}