Japan's nuclear regulatory body will consult experts about the most effective way to implement the "indoor sheltering" provision for people around nuclear power plants when accidents coincide with natural disasters.

Guidelines set by the Nuclear Regulation Authority after the 2011 triple meltdown at the Fukushima Daiichi nuclear power plant call for residents within 5 kilometers of a plant to evacuate immediately after a serious accident.

Residents living between 5 and 30 kilometers of the plant are asked to shelter indoors, but evacuate if radiation levels exceed a certain level.

The powerful earthquake that hit the Noto Peninsula in central Japan on New Year's Day destroyed many houses and structures, isolating many communities around the Shika nuclear power plant.

This prompted the authority to discuss how to keep residents safe if an accident at a nuclear plant coincides with a natural disaster.

Japan's Basic Disaster Management Plan calls for residents whose homes have collapsed to shelter at evacuation sites, and to evacuate if they cannot stay indoors.

The authority on Wednesday confirmed the effectiveness of combining evacuation and indoor sheltering to avoid radiation exposure.

The authority decided to set up a team including outside experts to consider how to flexibly judge when to call for indoor sheltering, when to lift such an instruction, and areas targeted, depending on how the natural disaster and nuclear accident are unfolding.

The authority's secretariat plans to compile a report by the end of fiscal 2024.