Document: NRC Regulatory Guide
Document ID: 8322a959-849d-4ec6-926e-1f30ed96d71f
Document Type: regulatory_guide
Title: Periodic Testing of Protection System Actuation Functions (Rev. 0)
Source: NRC Regulatory Guide Division 1
Source URL: https://www.nrc.gov/docs/ML0833/ML083300530.pdf
Revision Date: 2023-06
Chapter: 
Section ID: RG-1.22
CFR Part: 
CFR Title: 

Content:
n these cases, acceptable methods of including the actuation devices in periodic tests of the protection system, while avoiding the undesirable effects of operation of the actuated equipment, are: (1) testing the actuation devices and the actuated equipment2 individually or in judiciously selected groups, (2) preventing the operation of certain actuated equipment during a test of their actuation devices, and (3) designing the system such that operation of the actuated equipment requires the operation of more than one actuation device, each actuation device being individually testable. Examples of utilization of these methods are, respectively: (1) testing the actuation device for a containment spray pump separately from the actuation devices for the containment spray valves, (2) moving the circuit breaker for an emergency coolant pump to a test position that prevents power being supplied to the pump during a test closure of its circuit breaker, and (3) testing individually the two solenoid operated valves that act in coincidence to control compressed air to an isolation valve. Compared to a design that permits testing the operation of all devices associated with each protection system output signal, each of the methods discussed above can have two major disadvantages. First, the ability of a system to respond to a bona fide accident signal may be partially or completely 2 The actuated equipment is included in the periodic tests to provide assurance that the protection system can initiate its operation, as required by General Design Criterion 21. This safety guide does not address the functional performance testing of actuated equipment required by other General Design Criteria; neither does it preclude a design that fulfills more than one testing requirement with a single test. RG-1.22, Page 3 bypassed. In this case, the design should include provisions that prevent a complete bypass of any protective function and indicate the status of the protection system. The