Document: NRC Regulatory Guide
Document ID: 8e45dce1-e1e7-4415-b1dd-7e2a610e545b
Document Type: regulatory_guide
Title: Fire Protection for Nuclear Power Plants (Rev. 4)
Source: NRC Regulatory Guide Division 1
Source URL: https://www.nrc.gov/docs/ML2023/ML20231A835.pdf
Revision Date: 2023-06
Chapter: 
Section ID: RG-1.189
CFR Part: 
CFR Title: 

Content:
tance rating of the barrier. For this example, the TET limit for Brand X cable is 83 degrees C (181 degrees F) above the cable operating temperatures within the fire barrier system at the onset of the external fire exposure. The cable TET limits in conjunction with a posttest visual cable inspection and the Hi-Pot test described above should readily demonstrate the functionality of the cable circuit during and after a fire. The normal cable operating temperature can be determined by loading cable specimens installed within a thermal barrier system in the test configuration with rated voltage and current. The TET temperature limits for most cable insulation may be obtained from the manufacturer’s published data, which are given as the short-circuit rating limit. With the known TET and normal operating temperature for each thermal barrier system configuration, the maximum temperature rise limit within a fire barrier system may then be determined. DG-1359, Appendix B, Page B-9 REFERENCES FOR APPENDIX B B-1. National Fire Protection Association (NFPA), NFPA 251, “Standard Methods of Tests of Fire Resistance of Building Construction and Materials,” Quincy, MA.2 B-2. American Nuclear Insurers Information Bulletin 5 (79), “ANI/MAERP Standard Fire Endurance Test Method to Qualify a Protective Envelope for Class 1E Electrical Circuits,” July 1979. B-3. IEEE, IEEE 690-1984, “IEEE Standard for the Design and Installation of Cable Systems for Class 1E Circuits in Nuclear Power Generating Stations,” Piscataway, NJ.3 B-4. Underwriters Laboratories Inc. (UL), UL Subject 1724, Appendix B, “Qualification Test for Circuit Integrity of Insulated Electrical Wires and Cables in Electrical Circuit Protection Systems” (Paragraph B3.16), to “Outline of Investigation for Fire Tests for Electrical Circuit Protective Systems,” Issue No. 2, August 1991.4 2 The National Fire Protection Association (NFPA) makes important safety codes and standards available for free online,