About a century ago, a special era began for mankind - the time of studying first natural, and then artificially created radiation. In the middle of the century, which was called the atomic one, two opposite events occurred:
- first of all, it's the atomic bombing of Hiroshima and Nagasaki;
- secondly, for the first time in the world, a nuclear power plant was opened in Obninsk.
In the latter case, destructive energy has become creative for humanity. What are radioactive materials? What is a substance that can cause radiation?
What substances are radioactive
First you need to understand which substances belong to the class of radioactive. Mendeleev's periodic system includes 120 elements. Each of them consists of atoms, and the atoms of some substances can fall apart. This releases hazardous radiation.
Radioactive material is represented by all chemical elements located after lead. In total, more than 80 dangerous radioactive elements are known. For example, it is radium, francium, polonium, strontium,bismuth, germanium, cesium. Some of them are found in nature. Others are the work of man.
Properties of radioactive substances
The danger of these substances is due to the fact that they are, first of all, invisible to the human eye. They have no color, taste or smell. For many years a person can live near a source of radioactivity without suspecting anything about it. Another dangerous property of this class of substances is their ability to travel long distances from their source. At the same time, their decay does not depend in any way on the influence of environmental factors.
Nuclear danger cannot be eliminated by physical or chemical means. Radioactive substances can be found in the air, land, food. For example, vegetables such as cabbage and beets have been proven to contain the most radionuclides.
Natural radioactive elements
Radioactive material can be found in mineral deposits, in many rocks that can contain radioactive elements in varying amounts. For example, these are the oil-producing territories of Western Siberia. There are a large number of deposits of uranium, as well as those substances that are products of its decay - radon, radium. Also, radioactive material can enter the environment through state district power plants and thermal power plants, which can operate on certain types of coal.
Regions with natural radioactive emission
Examples of radioactive places onplanet Earth, where radiation is natural, may be the Indian beaches of Kerala, the Chinese province of Guangdong, where isotopes are found in the soil, as well as some sites in Brazil. Also, increased radiation of rocks is characteristic of some regions in France, Ukraine, Sweden.
Often, nuclear materials and radioactive substances are contained in building materials. Examples are building materials such as crushed stone, alum and phosphate rock. They contain a high amount of radionuclides, while being used in the construction industry everywhere. This leads to a multiple increase in the dose of gamma radiation inside buildings.
The use of radioactive materials in construction: an invisible danger
Such cases have been established more than once. For example, in Omsk, builders often used crushed stone mined in the regions of Northern Kazakhstan to fill concrete. It contained increased amounts of radioactive uranium, resulting in a significant increase in the level of gamma radiation in buildings.
A case has also been identified where radioactive building materials were used to build residential buildings. Such a violation was recorded in the Yekaterinburg region, at the Kostousovo station. Workers used sand containing radioactive thorium to build foundations, plaster work, and other types of finishes.
There have been a huge number of cases like these. In Kazakhstan, Transbaikalia andIn many other areas, substandard uranium ores were used by builders to sprinkle streets, playgrounds, courtyards. This led to a significant increase in the dangerous radiation field.
Artificial sources of radioactivity
Radioactive material can also be the work of man. There are various sources that pollute the environment with radionuclides:
- These are nuclear explosions used in oil extraction.
- Testing at military ranges.
- Nuclear fuel cycle enterprises.
- Accidents at nuclear power plants.
- Also dangerous is the fighting, which uses atomic bombs and shells.
- Burial of radioactive substances.
- Reckless use of various technical devices.
Transportation of radioactive substances
The transportation of radioactive materials takes place according to special rules, which are approved by the Federal Law "On Atomic Energy". For many enterprises, their transportation is an integral part of all activities. There is a special security system for the transport of these substances.
Fissile - these are substances whose nuclei begin to divide when neutrons are captured. Simply, their nuclei fall apart, and energy is released in the process. An example of fissile substances is uranium-235, uranium-233, plutonium-239, and others. fissile and radioactivematerials are prohibited from being transported through customs. Through customs control, their transportation across the border is prevented.
