Document: NUREG-0800
Document ID: 9f13abda-ee55-4fa1-8276-db55ac2094ef
Document Type: srp
Title: CONTROL ROOM HABITABILITY SYSTEM
Source: NUREG-0800
Source URL: https://www.nrc.gov/docs/ML0520/ML052070449.pdf
Revision Date: 2023-06
Chapter: 6
Section ID: 6.4
CFR Part: 
CFR Title: 

Content:
nt should not result in loss 25 of the system's functional performance. All the components of the control room emergency filter train should be considered active components. See Appendix A to this SRP for criteria regarding valve or damper repair. 3. Pressurization Systems 6.4-5 DRAFT Rev. 3 - April 1996 Ventilation systems that will pressurize the control room during a radiation emergency should meet the following requirements: a. Systems having pressurization rates of greater than or equal to 0.5 volume changes per hour should be subject to periodic verification (every 18 months) that the makeup is + 10% of design value. During plant construction or after any modification to the control room that might significantly affect its capability to maintain a positive pressure, measurements should be taken to verify that the control room is pressurized to at least 3.2-mm (1/8-in) water gauge relative to 26 all surrounding air spaces while applying makeup air at the design rate. b. Systems having pressurization rates of less than 0.5 and equal to or greater than 0.25 volume changes per hour should have identical testing requirements as indicated in (1) above. In addition, at the CP, combined license (COL), or standard design certification stage, an analysis should be provided (based on the 27 planned leaktight design features) that ensures the feasibility of maintaining 3.2- mm (1/8-in) water gauge differential with the design makeup airflow rate. 28 c. Systems having pressurization rates of less than 0.25 volume changes per hour should meet all the requirements for (2) above, except that periodic verification of control room pressurization (every 18 months) should be specified. 4. Emergency Standby Atmosphere Filtration System The atmosphere filtration system is reviewed by ETSB under SRP Section 6.5.1. The ETSB will determine the credit for iodineIodine removal for this system should be in accordance with the guidelines of Regulatory Guide 1.52 and will advise the AEB