The phenomena - reflection, absorption, refraction and scattering that accompany the spread of EMF depend on the frequency f, wavelength λ and the properties of the environment. When EMW are distributed in certain environment, part of their energy is converted into internal energy of the environment – it is heated and then we say that the environment absorb them (this heating is used in microwave ovens, induction furnaces, dielectric heating, electromagnetic therapy).

Electromagnetic waves (EMW) pass through a plate of PVC barriers, getinax, glass, etc. - dielectrics are transparent for them. At the same time they do not pass through a plate of copper, aluminum and others - metals are not transparent for them. It is important to note that one and the same substance can be transparent to the waves of one frequency, i.e., to pass them, and at the same time – not transparent for waves with different frequencies, i.e., to absorb or reflect them.

After years of research and study of the properties of the EMF Faraday discovered the following: a cage, the walls of which are made of metal in the form of a grid (non-solid barrier) for electromagnetic radiation with a certain wavelength, the cage has the property to reflect them. The application of this feature makes it possible to create a screen for EMR which in literature is known as Faraday’s cage or cage of Faraday.


There are two possible ways to protect against the harmful effects of electromagnetic radiation:

  • The first approach relies on the development of specific means to protect people working near the equipment - the source of electromagnetic radiation (EMR). This includes production of special protective clothing and personal protective equipment for personnel or protection of the room and area of residence, by special screens. They are made from textile fabrics (woven or knit) and in their structure electrically conductive threads are included.
  • The second approach involves screening (fencing) of the source of electromagnetic radiation (EMR). Where possible appliances and equipment shall be screened. For this purpose special materials are used for production of screens (screens, curtains, tents, blankets, etc.) which surround the source.


DIRECTIVE 2013/35/EU of the European Parliament and of the Council on the minimum health and safety requirements regarding the exposure of workers to the risks arising from physical agents (electromagnetic fields)