Are nuclear power plants safe?

The Tokyo Electric Power Company said on the 15th that white steam emerged from the reactor of Unit 3 of the Fukushima Daiichi Nuclear Power Plant, and Unit 4 exploded and a fire broke out. Japanese Prime Minister Naoto Kan instructed that the refuge radius of residents be extended from 20 kilometers to 30 kilometers around the first nuclear power plant. This data photo released by the Kyodo News on March 13 is the exterior of the Fukushima Daiichi Nuclear Power Plant in Japan, taken in October 2008. From left to right, they are Units 4, 3, 2, and 1.

Nuclear power generation is currently the most important way of peaceful use of nuclear energy. Under normal operating conditions, the radiation dose generated by a nuclear power plant to the surrounding public does not pose any danger to people.

In China, the national nuclear safety regulations require that the annual radiation dose of nuclear power plants to surrounding residents under normal operating conditions shall not exceed 0.25 mSv, and the actual radiation dose generated by nuclear power plants is far below this limit. Numerous studies and survey data indicate that the impact of nuclear power plants on public health is far less than some health risks that people often encounter in their daily lives, such as smoking and air pollution. Therefore, the environmental safety of nuclear power plants under normal operating conditions has been widely accepted by people.

According to the National Atomic Energy Agency website, the core of nuclear power safety is to prevent the leakage of radioactive fission products in the reactor to the surrounding environment. In order to prevent the leakage of radioactive fission products in the reactor core, an appropriate physical barrier is set up in the project. Nuclear power plants generally have three safety barriers, which are fuel element cladding, primary circuit pressure boundary and containment.

Before the Fukushima nuclear power plant accident in Japan, there have been two major nuclear accidents worldwide, namely the Sanli Island nuclear power plant accident and the Chernobyl nuclear power plant accident. On March 28, 1979, a severe accident occurred at the Sanli Island nuclear power plant in the United States, and part of the reactor core melted and collapsed. However, due to the containment effect of the primary circuit pressure boundary and the containment, the radionuclides leaking into the surrounding environment are minimal, and there is no harm to the environment and the health of the public. Only three power station workers are slightly higher than the quarterly dose management limit Radiation exposure. On April 26, 1986, the Chernobyl nuclear power plant accident occurred in the former Soviet Union. In April 1996, more than 800 experts from 71 countries and 20 organizations met to evaluate the actual consequences of the Chernobyl nuclear power plant accident. The evaluation results showed that only 28 of the nuclear power plant staff and those who helped deal with the consequences of the accident died from radiation exposure. Over 100,000 residents evacuated from the polluted area and people still living in the lightly affected areas, the doses they receive in their lifetime are similar to or lower than the doses they receive from natural radiation sources in their lifetime.