Nuclear power plants—Instrumentation important to safety—Radiation monitoring for accident and post-accident conditions—Part 4:Equipment for continuous in-line or on-line monitoring of radioactivity in process streams
GB/T 12726 "Nuclear Power Plants — Instrumentation Important to Safety — Radiation Monitoring for Accident and Post-accident Conditions" is comprised of 4 parts:
— Part 1: General Requirements;
— Part 2: Equipment for Continuous Off-line Monitoring of Radioactivity in Gaseous Effluents and Ventilation Air;
— Part 3: Equipment for Continuous High Range Area Gamma Monitoring;
— Part 4: Equipment for Continuous In-line or On-line Monitoring of Radioactivity in Process Streams.
This part is Part 4 of GB/T 12726.
1 Scope
This part of GB/T 12726 specifies general guidance on the design principles and performance criteria for equipment for continuous in-line or on-line monitoring of radioactivity in process stream in nuclear power plants for accident and post-accident conditions.
General requirements for technical characteristics, test procedures, radiation characteristics, electrical, mechanical, and environmental characteristics are given in GB/T 12726.1-2013. These requirements are applicable in this part unless otherwise stated.
This part is only applicable to continuous in-line or on-line measurement, i.e. monitors for which the detector measures radioactivity by being positioned in the process stream (i.e. immerged in) or adjacent to the process stream (i.e. viewing straight through a pipe or tank). It does not apply to monitors for which the detector measures a representative proportion of the stream at some remote location (sampling assembly), which are within the scope of GB/T 12726.2.
This part is only applicable to monitors for accident and post-accident conditions. Process stream radiation monitoring equipment for normal and incident conditions are within the scope of IEC 60768.
2 Normative References
The following documents are indispensable for the application of this document. For dated references, only the dated editions apply. For undated references, the latest editions (including any amendments) apply.
GB/T 2423.3-2006 Environmental Testing for Electric and Electronic Products — Part 2: Tests Methods — Test Cab: Damp Heat Steady State (IEC 60068-2-78:2001, IDT)
GB/T 2423.4-2008 Environmental Testing for Electric and Electronic Products — Part 2: Tests Methods — Test Db: Damp Heat, Cyclic (12h+12h Cycle) (IEC 60068-2-30:2005, IDT)
GB/T 12726.1-2013 Nuclear Power Plants — Instrumentation Important to Safety — Radiation Monitoring for Accident and Post-accident Conditions — Part 1: General Requirements (IEC 60951-1:2009, IDT)
IEC 60768 Nuclear Power Plants — Instrumentation Important to Safety — Equipment for Continuous In-line or On-line Monitoring of Radioactivity in Process Streams for Normal and Incident Conditions
3 Terms and Definitions
For the purposes of this document, the terms and definitions given in GB/T 12726.1-2013 apply.
4 Design Principles
Foreword II
Introduction III
1 Scope
2 Normative References
3 Terms and Definitions
4 Design Principles
4.1 General
4.2 Basic requirements related to functions
4.3 Range of measurement
4.4 In-line detectors mechanical features
5 Functional Testing
5.1 General
5.2 Environmental performance test
Table 1 Standards of SAC/TC 30/SC 2/SC 3 IV
Table 2 Additional Tests to Complement the General Tests Required in GB/T 12726.1-2013
