electromagnetic field


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electromagnetic field

Public health
An invisible field of electromagnetic radiation on the spectrum of energetic particles that move as quanta (radiowaves, infrared, visible light, UV light and gamma radiation). EMFs are generated by moving electric charges that propagate outward from any object carrying an electric current, and result from: 
(1) The electric field that pushes or pulls ions toward or away from the field; the electrical component of an EMF is blocked by most objects, from skin to concrete, and has a strength of 1 mV/m2, which is similar to the strength of the cells’ intrinsic electrical activity;
(2) The magnetic field that acts on moving particles, pushing them perpendicularly to their direction of motion, which passes through most matter without losing strength; the actual power generated by a magnetic field is a few milligauss (1% of the strength of the earth’s magnetic field).

Tumour cells exposed in vitro to extremely low electromagnetic fields (ELF) of 60-Hz electromagnetic radiation from electrical distribution systems (power lines, video display terminals, household appliances) have increased mitotic activity; some reports have suggested that ELF radiation is associated with a 1.5–2.5-fold increase in leukaemia, lymphomas and intracranial malignancy, especially in children living near either 765-kV power lines or 15-kV distribution lines. Although ELF increases ornithine decarboxylase activity or cell membrane resistance to spontaneous lysis, the relationship of ELF to malignancy is controversial and inconclusive.

electromagnetic field

Abbreviation: EMF
The region in space in which the photons produced by moving electric charges have an effect. EMFs can be produced by power lines, radio waves, and microwaves. The energy produced in an EMF increases as the frequency of the photons increases, and EMFs produced by very high frequency photons (e.g., xrays and gamma rays) are sufficiently energetic to induce cancer.
See also: field

electromagnetic field (EMF),

n three-dimensional areas that represent the mutual interaction of magnetic and electric forces.
References in periodicals archive ?
The findings to date do not support claims that electromagnetic fields are harmful to a person's health,'' said committee chairman Charles F.
From the literature it is clear that irradiation with electromagnetic fields (EMF) affect the ionic channels permeability in the membrane of cells, and consequently influence the transport of ions into the cells and cause biological changes in the organisms (Galvanoskis and Sandblom, 1998).
Rammal et al reported decreasing of antioxidant potential of plant Lycopersicon esculentum by assessment of DPPH radical scavenging of electromagnetic field treated samples [22].
To make sure that only this ordinary microstrip line is illuminated by the electromagnetic field, the nonlinear component is placed outside the cell through a hole.
Therefore, the electromagnetic fields due to an inclined lightning channel are strongly dependent on the channel angle, the angle of the observation point and the ground reflection factor as well as other current and geometrical parameters.
The health authorities have determined that the threshold limit values for electromagnetic fields around transmitters in mobile phones and other equipment should be the same as those recommended by the International Commission on Non-ionising Radiation Protection (ICNIRP).
The carried out simulation it is crucial to determine the value of radiation strength of the electromagnetic field generated by the antenna in space, in a specific direction from the antenna.
The KSU study is seconded by a group of researchers from King Fahd University of Petroleum and Minerals (KFUPM) who had surveyed a large number of sites for measuring the level of electromagnetic fields near high-voltage lines and power-generating stations.
To analyze the characteristics of a particular type of heating oven it is necessary to find the electromagnetic field distribution inside the applicator for real loads.
On the other hand, in the centre of interest have been possible effects of the technical environment, like electromagnetic fields, on the human physiology and health.
After constructing a similar coil as those commonly used in our operating theatres around a non-conducting core, we subjected it to an electromagnetic field as generated by a typical active theatre extension lead.

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