What is radiation?

Radiation exists in the entire universe, and is divided into ionizing radiation and non-ionizing radiation. In the field of nuclear energy, people are mainly concerned about the possible health effects of ionizing radiation and their protection. Ionizing radiation is usually simply referred to as radiation or radiation exposure.

Human beings have been exposed to natural sources of ionizing radiation throughout history, including cosmic rays and radiation produced by radionuclides on the earth. Radiation is ubiquitous, and radiation exposure exists in food, houses, sky and land, landscapes and plants, and even people. The collective radiation dose to humans is mainly from natural background radiation and medical treatment. The radiation dose generated by nuclear power plants is very small, about 0.25%.

According to the website of the National Atomic Energy Agency, people have established an effective radiation protection system based on a large number of theoretical and experimental studies on the mechanism of radiation health hazards, and have continuously developed and perfected it. At present, the three principles of radiation protection generally adopted in the world are: the legitimacy of practice, the optimization of the protection level and the personal dose limit. International basic safety standards stipulate that the individual dose limit for public exposure is 1 mSv per year, while the personal dose limit for occupational exposure is 20 mSv per year.