On October 18, Northeast China Nuclear and Radiation Oversight Station, Ministry of Ecology and Environment of the People’s Republic of China (hereinafter referred to as the MEEP/NECNROS) carried out on-site supervision and inspection on the supervisory and witness points conducting the main loop leakage rate test of the 154 bar pressure platform and water pressure test of the 228 bar pressure platform respectively when doing the Unit 5 cold-state function test (hereinafter referred to as cold test) of Hongyanhe nuclear power plant. The supervisor carried out field inspection regarding the appearance check of the main equipment for the three loops, the gauge pressure monitoring, master control room monitoring, acoustic emission monitoring and so on respectively and confirmed the leakage rate and that the site status can meet the requirements.

Primary loop water pressure test is also known as cold test and it mainly conducts bulge test through the reactor coolant system, auxiliary pipeline and other means. Cold test is to put the primary loop under high test pressure without loading nuclear fuel so as to check whether there is any leakage or potential safety hazards. It is the first comprehensive test after the nuclear power units entering the system debugging stage and it is the first pass of the "physical examination" of the nuclear power plant. The passing of the "big test" in performance testing of the unit marks that Hongyanhe No. 5 unit has fully entered the debugging stage.