Electromagnetic fields and radiation surround useverywhere. Just click the switch - and the light comes on, turn on the computer - and you're on the Internet, dial the number on your mobile phone - and you can communicate with distant continents. In fact, it was electrical devices that created the modern world as we know it. However, recently the question has been increasingly raised that electromagnetic fields (EMF) generated by electrical equipment are harmful. Is it so? Let's try to understand.
Let's start with the definition.Electromagnetic fields, as is known from the school course of physics, represent a special kind of matter. A key feature of such fields is the ability to interact in a certain way with bodies and particles that have an electric charge. As the name implies, electromagnetic fields are a combination of magnetic and electric fields, and in this case they are so closely interrelated that they are considered to be a single whole. The features of interaction with charged objects are explained with the help of the Lorentz force.
For the first time, electromagnetic fields were mathematicallyexpressed in the theory of Maxwell in 1864. Actually, it was he who revealed the indivisibility of magnetic and electric fields. One of the consequences of the theory was the fact that any perturbation (change) in the electromagnetic field is the cause of the appearance of electromagnetic waves propagating in the vacuum at the speed of light. Calculations have shown that light (all parts of the spectrum: infrared, visible, ultraviolet) is just an electromagnetic wave. In general, by classifying radiation along the wavelength, distinguish between X-ray, radio, and so on.
The appearance of Maxwell's theory was preceded by worksFaraday (in 1831) on the study of electromagnetic induction in a conductor moving or located in a periodically changing magnetic field. Earlier, in 1819, H. Oersted drew attention to the fact that if a compass was placed next to a conductor with a current, then its arrow deviates from the natural magnetic pole of the Earth, suggesting a direct connection between the magnetic and electric fields.
All this indicates that anyan electrical appliance is a generator of electromagnetic waves. This property is particularly pronounced for some specific instruments and high-current circuits. Both the first and second are now present in almost every home. Since EMF is distributed not only in conductive materials, but also in dielectrics (for example, vacuum), the person is constantly in the zone of their action.
If earlier, when the room was only"Ilyich's bulb", the question did not bother anyone. Now everything is different: the measurement of the electromagnetic field is performed using special instruments for measuring the field strength. Both components of the EMF are fixed in a certain frequency range (depends on the sensitivity of the device). The document SanPiN specifies PDN (permissible norm). At enterprises and large companies, PDN EMF checks are periodically performed. It is worth noting that the final results of research on the impact of EMF on living organisms are still not there. Therefore, for example, when working with computer equipment, it is recommended to organize 15-minute breaks after every hour - just in case ... Everything is explained quite simply: there is a magnetic field around the conductor, hence EMF is also present. The equipment is completely safe in the event that the power cord is pulled out of the outlet.
Obviously, to completely abandonthe use of electrical equipment few people will dare. However, you can additionally secure yourself by connecting home devices to a grounded network, which allows the potential not to accumulate on the housing, but to "drain" into the ground loop. Various extensions, especially those wound in rings, enhance EMF due to mutual induction. And, of course, you should avoid the close placement of several devices.
