During routine test, staff closed cooling water isolation valve for standby equipment longer than permitted under technical specifications

Hong Kong authorities have stressed that an operational glitch at a nuclear plant in neighbouring Shenzhen involving the closure of a cooling water isolation valve earlier this week posed no risk to public health or the environment.

The Security Bureau said on Sunday that Guangdong’s Nuclear Emergency Committee Office had notified it of an operational event at Ling Ao Nuclear Power Station in mainland China, that occurred last Thursday.

The plant, about 50km (31 miles) north of urban Hong Kong, was undergoing a scheduled refuelling overhaul of one of its units at the time, a bureau spokesman said.

During a routine test, staff closed a cooling water isolation valve for the standby equipment to adjust the water flow before restoring water levels to normal later that day.

The spokesman said the valve had remained closed longer than permitted under technical specifications, and the incident was subsequently classified as a Level 0 deviation on May 8.

Under the International Nuclear and Radiological Event Scale, a Level 0 deviation indicates an event with no safety significance.

Source: News - South China Morning Post