There is no radioactive radiation distance without protection. Because it is impossible to avoid radiation from radioactive rays, background exposure exists around the environment in everyday life. The sources of rays for background irradiation are cosmic rays, rays present in the earth, and rays produced by isotopes of hydrogen and carbon elements in the human body.
There are three basic methods of radiation protection: first, time protection; second, distance protection; third, shielding protection.
Expanded Information:
People are familiar with and unfamiliar with the dangers of radiation. In the common people's impression, is associated with the explosion of the powerful atomic bomb, hydrogen bomb, with the world's peaceful use of nuclear energy calls for the rise of the ban on the use of nuclear weapons, nuclear testing has been greatly reduced, people seem to have been away from radiation hazards.
However, with the wide application of radioisotopes and ray devices in various fields such as industry and agriculture, medical care and scientific research, the possibility of radiation hazards is increasing.
On September 30, 1999, a serious nuclear leak occurred at JCO's uranium enrichment processing plant in Ibaraki Prefecture, Japan, where three workers suffered severe radiation exposure and were unconscious when rescuers brought them to a local hospital.
At the same time, the accident caused the adjacent areas around the plant to suffer varying degrees of contamination, the radiation level is 10,000 times the normal value of the danger of radiation once again to mankind to sound the alarm.
Baidu Encyclopedia - Radiation
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