Document: NRC Regulatory Guide
Document ID: 4b34bbdf-f837-4227-9a0d-3f0ad3778b30
Document Type: regulatory_guide
Title: Protection of Nuclear Power Plant Control Room Operators Against an Accidental Chlorine Release (Rev. 1)
Source: NRC Regulatory Guide Division 1
Source URL: https://www.nrc.gov/docs/ML1229/ML12298A134.pdf
Revision Date: 2023-06
Chapter: 
Section ID: RG-1.95
CFR Part: 
CFR Title: 

Content:
U.S. NUCLEAR REGULATORY COMMISSION REGULATORYGUIDE OFFICE OF STANDARDS DEVELOPMENT REGULATORY GUIDE 1.95 PROTECTION OF NUCLEAR POWER PLANT CONTROL ROOM OPERATORS AGAINST AN ACCIDENTAL CHLORINE RELEASE Revision 1 January 1977 A. INTRODUCTION Criterion 4, "Environmental and missile design bases," of Appendix A, "General Design Criteria for Nuclear Power Plants," to 10 CFR Part 50, "Licens- ing of Production and Utilization Facilities," re- quires, in part, that structures, systems, and compo- nents important to safety be designed to accom- modate the effects of and to be compatible with the environmental conditions associated with operation, maintenance, testing, and postulated accidents. Criterion 19, "Control room," requires that a control room be provided from which actions can be taken to operate the nuclear power unit safely under normal conditions and to maintain it in a safe condition un- der accident conditions. The release of chlorine could potentially result in the control room operators becoming incapacitated. This guide describes design features and procedures that are acceptable to the NRC staff for the protec- tion of nuclear plant control room operators against an accidental chlorine release. The Advisory Com- mittee on Reactor Safeguards has been consulted concerning this guide and has concurred in the regulatory position. B. DISCUSSION Many nuclear power plants use chlorine for water treatment in the circulating water system and in other auxiliary systems. Chlorine is normally stored on the site as liquified gas in one-ton tanks or large railroad cars (typically 16 to 55 tons). * Lines indicate substantive changes from previous issue. Regulatory Guide 1.78, "Assumptions for Evaluating the Habitability of a Nuclear Power Plant Control Room During a Postulated Hazardous Chemical Release," identifies chlorine as a hazardous chemical which, if present in the control room at- mosphere in sufficient quantity, could result in the control room becoming