On January 16, the comprehensive tests of the New Safe Confinement radiation monitoring system were started. Emergency situations are simulated during the tests and response of specific systems on them is checked.
Leading engineer of the Radiation Safety Shop Yevhen Stromko provides comments regarding this activity: "Tests are carried out as close as possible to the normal operating conditions of the facility. We give alarms to the safety controller, which sends signals to NSC technological systems. For example, an alarm in the ventilation system should lead to the closure of the door, shut-off of air ducts, which in turn will activate the air filtration systems. A sound and light alarm is generated".
During three days, from January 16 to January 18, similar tests were carried out in all zones of NSC. The first zone includes the main space of NSC (space under the arch) and a unit of liquid radioactive waste (hereinafter: RAW). The second zone represents the premises where radioactive waste will be managed. The third zone is intended for the personnel, this is the cleanest zone in terms of radiation safety.
"After works conducting in zones one and two, we started testing of the monitoring system for controlled release into NSC ventilation stack. In addition to these tests, also air locks performance was examined. We checked the exhausting ventilation of the main space and radiation control system located within its boundaries.
This is the most important system from the point of view of significance and safety. It assesses performance of NSC in terms of its function – retention of radioactivity in its space", — concluded Yevhen.
Read more: Project "New Safe Confinement Construction"
The main participants of NSC project took part in the testing: ChNPP, NOVARKA, Shelter Object Implementation Plan Project Management Unit (hereinafter: PMU) and the State Nuclear Regulatory Inspectorate of Ukraine.
From PMU side, providing the expert support to ChNPP, Leading engineer Maksym Saveliev commented the testing: "This is the last stage of the tests carried out by the Contractor [NOVARKA — Ed.] in presence of the Client and PMU representatives. The goal is to make sure that the radiation control system functions according to the design criteria.
The system is automated, that is, it works with a human's participation, but some safety-related commands are executed unconditionally and automatically. For example, in the case of an aerosol level excess signal, ventilation is shutdown immediately. After that, the personnel decides how to act in such a situation".
After testing of all systems it is planned to conduct 72-hour simulation of NSC functioning with all equipment involvement. Chornobyl Nuclear Power Plant will perform the simulation under control of the Contractor — NOVARKA.
In case of a successful simulation and testing NSC will be ready to obtain a permit for pilot and industrial, and subsequently for industrial operation.
