TOKYO - A reactor at the Takahama nuclear plant in central Japan marked its 50 years of operations on Thursday, becoming the first in the country to reach the milestone.

The No 1 reactor of the facility in Fukui prefecture is the oldest operational nuclear power reactor in the country. It began commercial operation in November 1974, as the eighth commercial reactor in the country. All the older ones have been decommissioned.

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Last month, Japan's Nuclear Regulation Authority (NRA) approved changes to safety regulations at the plant, allowing the Takahama No 1 reactor to operate beyond 50 years.

The operator, Kansai Electric Power Company, applied to the NRA in November last year to operate the plant for a further 10 years after conducting an aging technical evaluation and formulating a long-term facility management policy.

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In Japan, reactors are allowed to operate for up to 60 years. Laws were revised in May last year to allow them to operate beyond that limit by excluding time spent on inspections and other periods they are offline when calculating the total service life.