Claimed to be the world’s first AP1000 nuclear power plant, Sanmen is expected to be commissioned for operations, as the test has confirmed that the reactor systems meet design pressures under operating and accident conditions.

In addition, the test signified the completion of the plant’s design and construction programs.

According to the firm, the test was completed within four hours with the unit’s reactor systems successfully maintaining a test pressure of 3,107 psig (pounds per square inch gauge) for 10 minutes without leakage.

The test also cleared the way to carry out hot functional test and inspection of initial fuel load. The hot functional test will examine all plant systems prior to loading fuel in the reactor.

Westinghouse is also planning to carry out CHT at Haiyang Unit 1 in Shandong Province in the coming weeks.

The company plans to use the best practices resulting from each CHT in the next successive tests conducted at other AP1000 plant construction projects.

The projects comprise of Sanmen Unit 2 and Haiyang Unit 2, in addition to the four units under construction in the US.

Westinghouse new plants and major projects senior vice president Jeff Benjamin said: "The commissioning and testing team performed the cold hydrostatic test in a safe and event free manner which was an important factor in the test.

"The successful completion of cold hydrostatic test is a key step in the commissioning for the AP1000 plant and puts us in a great position to load fuel – a significant milestone we expect to complete at Sanmen 1 by year end."