Abstract: There is a 5 MWe graphite reactor in operation in Yongbyon, North Korea. In case of a nuclear accident, China could have to take emergency response actions as a result of possible radioactive materials released into environment due to the accident, which requires China to make appropriate emergency preparedness. Transboundary emergency of the 5 MWe graphite reactor in Yongbyon is analyzed from two aspects based on limited information: international planning zone and distance, and transboundary emergency practices of Chernobyl nuclear accident. The analysis result shows that it is unlikely that China's territory is within emergency planning zones and distances of the 5 MWe graphite reactor in Yongbyon. China's emergency preparedness for transnational emergency due to its nuclear accident should focuse on local food and trade restrictions.

Key words: Yongbyon, nuclear accident, emergency planning zone and distance, transboundary emergency, emergency preparedness