## 2 EMF Exposure Perturbation Effects  
In diverse circumstances, EMFs are expended daily in numerous cordial commitments. Moreover, they are engaged effectively in medical actions. Contrarily, when such fields are activated unintentionally, they may yield negative effects. The exposure to such fields could disturb apparatuses' functioning and provoke adverse BEs in living tissues. Such concerns are closely allied to the nature of the field and the radiated matter. The field intensity and frequency characterize EMFs, while the material and structural assets depict matter. The effects of EMF radiation can be divided into two sets regarding the ranges of frequency. One covers the range shared by radio, microwaves, and infrared waves that yield non-ionizing exposure, while the second concerns the range split into ultraviolet, X-, and gamma rays that fashion ionizing radiation. In this last range, field radiation on living tissues would likely cause serious adverse health effects by generating tissue harm. EMFs in the non-ionizing class operate safely in frequent circumstances but can also provoke adverse effects for excessive field strengths and exposure durations. Wireless energy transfer and propagation devices involve non-ionizing EMF exposures in the ranges of, respectively, low frequency up to 300 kHz and RF, at 10\({}^{5}\)-3 \(\times\) 10\({}^{11}\) Hz. Two categories of EMF exposures are related to the distance between the source and the target. In the first, the source is close to the target, interacting in a near-field mode focused on a point of the target, while in the second, the source is distant (approximately higher than a wavelength for RF) generating a whole target homogenous far field exposure (see Section 6 for more details). The interaction between the field and the target is dependent upon the strength and frequency of the field, the exposure duration, and the properties of the target matter. In the case of living-tissue targets, the degree of EMF exposure is evaluated by the tissue-specific absorption rate (SAR) in W/kg. This power density indicates the level of dissipated energy and its conversion to heat in a given exposure duration. This thermal outcome corresponds to the actual thermal BE of living tissues due to EMF exposure. The safety standards' fixed limits for EMF exposures correspond to the SAR, consequent temperature rise, and EMFs induced in the living tissues. Such thresholds are established functions of the specifications of the source and tissue, as well as the exposure circumstances and duration. Such data designate the specific part of the tissue, the quality of the exposed subject (human, animal, plant, etc. ), and the nature and duration of the exposure for the different situations of the subject exposed, which is related to its link with the source (fabricator, consumer, user, nearby, etc.). Excessive field strengths and exposure durations could produce a high SAR and disproportionate temperature rise, leading to adverse non-thermal BEs. These can trigger molecular disturbances, leading to tissue damage [14; 15; 16; 17; 18; 19]. Additionally, fortuitous EMF exposures in the range of an ionizing frequency can cause dangerous adverse effects related to molecular disorders, triggering tissue damage because of the high energy of photons or particles. In the case of target devices, which are usually protected against EMF radiation by the manufacturers' safety regulations, the constancy of a device can be verified via an EM compatibility (EMC) analysis. In case the operation of the device uses EMF, exposure to external field radiation or the introduction of EM-sensitive materials could disturb the device's own EMF and, thus, its constancy and reliability. Such effects would be amplified in medical devices operating in proximity to or embedded in tissues.