With regard to ionizing radiation, the UNSCEAR report states that the average annual radiation dose to an individual from natural background radiation is about 2.4 mSv (mSv stands for millisieverts). With regard to ionizing radiation, the UNSCEAR report states that the average annual radiation dose to an individual from natural background radiation is about 2.4 mSv/year. The international standard “International Basic Safety Standards for Ionizing Radiation Protection and Radiation Source Safety (IAEA No. 115)” and China’s national standard “Basic Standards for Ionizing Radiation Protection and Radiation Source Safety (GB18871-2002)” stipulate that: the annual average effective dose limit for the public is 1 mSv/year; the annual average effective dose for radiation workers is not limited to 20 mSv/year, and the standard The dose limit value does not include natural background dose and medical dose. Radiation protection 360 website (www.fushe360.com) collects and summarizes some reference values of ionizing radiation doses to which human beings are more frequently exposed, for the reference of netizens. Certain high background areas in China 3.70mSv/year Brick house 0.75mSv/year Fruit, grain, vegetables, air 0.25mSv/year Soil 0.15mSv/year Beijing to Europe by air once round trip 0.04mSv/time Living near a nuclear power plant 0.01mSv/year Medical CT 8mSv/time Chest X-ray 1.1mSv/time Chest film 0.2mSv/time Cranial CT 2mSv/time Chest CT 8mSv/time Abdomen CT 10mSv/time Pelvis CT 10mSv/time Smoking 20 cigarettes per day 0.5~2mSv/year Subway security passengers Less than 0.01mSv/year