A three-day conference hosted by the UN atomic agency started in Vienna on Monday aimed at improving public communication in a nuclear accident, more than a year since Japan's devastating Fukushima disaster.

"The objective of the meeting is to identify and analyse lessons learned from that accident and discuss best practices for improving the dissemination of information," the International Atomic Energy Agency said in a statement.

The 180 participants from 63 countries were due to share experiences and recommendations not only from Fukushima but also from the world's two other major nuclear accidents, Chernobyl in Ukraine in 1986 and Three Mile Island in the United States in 1979.

The meeting brings together national emergency response agencies, nuclear regulatory, safety and technical support organisations, nuclear power plant operators, 13 international bodies, NGOs and the media.

The gathering is among steps agreed under the IAEA's "Action Plan on Nuclear Safety" approved in the wake of March 2011's Fukushima accident.

Other measures include enhancing and strengthening IAEA expert "peer reviews" of the world's roughly 440 nuclear power facilities, developing more robust and effective national regulatory bodies and strengthening emergency preparedness.

An estimated 160,000 people were forced to evacuate the area around Fukushima Daiichi after a tsunami triggered by a huge earthquake knocked out cooling systems and triggered multiple reactor meltdowns.

The disaster was compounded, the IAEA has said, by "human and managerial failings." Many parts of a 20-kilometre (12-mile) exclusion zone around the plant are likely to remain uninhabitable for years, perhaps decades.