What is ISO 20890‑4 about?
ISO 12749-4 is the fourth part of the multi-series European standard that specifies guidelines for pre-service inspection (PSI) and in-service inspections (ISI) for reactor coolant circuit components of light water reactors and their installations as direct or remote visual testing in the form of a general visual testing (overview), or selective visual testing (specific properties).
ISO 20890‑4 focuses on the requirement of remote (mechanized) visual testing but also specify global requirements for direct visual testing.
Note: Data concerning the test section, test extent, inspection period, inspection interval and evaluation of indications is defined in the applicable national nuclear safety standards.
Note: ISO 20890‑4 is not applicable to tests in respect to the general state that are carried out in conjunction with pressure and leak tests and regular plant inspections.
ISO 20890‑4 guidelines are also applicable to other components of nuclear installations.
Who is ISO 20890‑4 for?
ISO 20890‑4 on light water reactors is applicable to:
- Nuclear power plants
- Mechanical Engineers
- Chemical engineer
- Nuclear research organisations
- Nuclear research scientists and researchers
- Nuclear regulatory authorities
Why should you use ISO 20890‑4?
Light-water reactors (LWRs) are neutron reactors in which normal water serves as both their coolant and neutron moderator, while solid forms of fissile elements serve as their fuel.
ISO 20890‑4 provide guidelines for pre-service inspection (PSI) and in-service inspections (ISI) for reactor coolant circuit components of light water reactors, which extends the service life and efficiency of the light water reactor.
ISO 20890‑4 specifies test methods that allow deviations from the expected state to be recognised, requirements for the equipment technology and test personnel, the preparation and performance of the testing as well as the recording to ensure the reliability and comparability of tests performed on reactor coolant components of light water reactors.
Pre-service inspection (PSI) and in-service inspections (ISI) of reactor coolant circuit components of light water reactors and their installations are critical procedures that should be carried out in accordance with defined instructions and guidelines.
Overall, ISO 20890-4 provides guidelines for pre-service and in-service inspection of reactor coolant circuits using automated ultrasonic testing devices which will benefit the users as they can inspect the components earlier than they will break down and therefore save from any accident conditions.