Electromagnetic fields surround us everywhere. Depending on their wave range, they can act differently on living organisms. Non-ionizing radiation is considered more benign, however, they are sometimes unsafe. What are these phenomena, and what effect do they have on our body?
What is non-ionizing radiation?
Energy is distributed in the form of small particles and waves. The process of its emission and propagation is called radiation. According to the nature of the impact on objects and living tissues, two main types of it are distinguished. The first - ionizing, is a stream of elementary particles that are formed as a result of the fission of atoms. It includes radioactive, alpha, beta, gamma, X-ray, gravitational and Hawking rays.
The second type of radiation includes non-ionizing radiation. In fact, these are electromagnetic waves whose length is more than 1000 nm, and the amount of released energy is less than 10 keV. It acts like microwavesreleasing light and heat as a result.
Unlike the first type, this radiation does not ionize the molecules and atoms of the substance it affects, that is, it does not break the bonds between its molecules. Of course, there are exceptions to this as well. So, certain types, for example, UV rays can ionize a substance.
Types of non-ionizing radiation
Electromagnetic radiation is a much broader concept than non-ionizing. High-frequency X-rays and gamma rays are also electromagnetic, but they are harder and ionize matter. All other types of EMR are non-ionizing, their energy is not enough to interfere with the structure of matter.
The longest among them are radio waves, whose range ranges from ultra-long (more than 10 km) to ultra-short (10 m - 1 mm). Waves of other EM radiations are less than 1 mm. After radio emission comes infrared or thermal, its wavelength depends on the heating temperature.
Visible light and ultraviolet radiation are also non-ionizing. The first is often called optical. With its spectrum, it is very close to infrared rays and is formed when bodies are heated. Ultraviolet radiation is close to X-ray, therefore it may have the ability to ionize. At wavelengths between 400 and 315 nm, it is recognized by the human eye.
Sources
Non-ionizing electromagnetic radiation can be of both natural and artificial origin. One ofThe main natural source is the Sun. It sends out all kinds of radiation. Their complete penetration to our planet is prevented by the earth's atmosphere. Thanks to the ozone layer, humidity, carbon dioxide, the effect of harmful rays is greatly mitigated.
For radio waves, lightning can serve as a natural source, as well as space objects. Thermal infrared rays can emit any body heated to the desired temperature, although the main radiation comes from artificial objects. So, its main sources are heaters, burners and ordinary incandescent bulbs that are present in every home.
Radio waves are transmitted through any electrical conductors. Therefore, all electrical appliances, as well as devices for radio communication, such as mobile phones, satellites, etc., become an artificial source. Special fluorescent, mercury-quartz lamps, LEDs, excilamps spread ultraviolet rays.
Influence on a person
Electromagnetic radiation is characterized by wavelength, frequency and polarization. From all these criteria and depends on the strength of its impact. The longer the wave, the less energy it transfers to the object, which means it is less harmful. Radiation in the decimeter-centimeter range is the most detrimental.
Non-ionizing radiation with prolonged exposure to humans can cause harm to he alth, although in moderate doses they can be useful. Ultraviolet rays can cause burns to the skin and cornea, causevarious mutations. And in medicine, they synthesize vitamin D3 in the skin, sterilize equipment, and disinfect water and air.
In medicine, infrared radiation is used to improve metabolism and stimulate blood circulation, disinfect food. With excessive heating, this radiation can greatly dry out the mucous membrane of the eye, and at maximum power it can even destroy a DNA molecule.
Radio waves are used for mobile and radio communications, navigation systems, television and other purposes. Constant exposure to radio frequencies from household appliances can increase the excitability of the nervous system, impair brain function, and adversely affect the cardiovascular system and reproductive function.
