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 ?
In this context the present study examined the impact of high frequency electromagnetic fields (HF-EMF) at 900 MHz and 1800 MHz, used in mobile phone on the survival rate and on the morphology of bacterial cells.
Environmental scientist Dr Cindy Sage said: "Reductions in preventable exposures to electromagnetic fields and radio-frequency radiation should be a top public health priority.
Our model found that electromagnetic fields evoked pain that is perceived before neuroma formation; subjects felt pain almost immediately,' Romero-Ortega said.
The domains also share a set of primary and derived SI units for communicating measurements of the various properties of electromagnetic fields.
They give the microrobots their shape during the manufacturing process, and make them move and swim when an electromagnetic field is applied.
The EMF Directive exists to ensure the safety and health of workers involved in situations where electromagnetic fields are present due to the utilisation of electricity in the workplace.
The main body of the text is comprised of two parts covering fundamental theories and a variety of advanced topics and the second part covers the major computational methods utilized in analyzing electromagnetic fields for a variety of engineering applications.
S et al reported that electromagnetic fields decreased protein content and increased catalase activity of Valerian leaves, specially in dry treated seeds [8].
One of the challenges is the evaluation of electromagnetic field coupling to TL connected with a nonlinear component and the prediction of the transmitted power from this nonlinear component towards the next element/device.
Electromagnetic fields are created around an electric current, and are commonplace in our environment, particularly due to computer screens and mobile phones.
The electromagnetic fields associated with a lightning channel can be considered as a source of lightning induced voltage on power lines whereby they are strongly dependent on the shape of lightning channel, lightning current parameters at different heights along the lightning channel and a number of geometrical parameters [1-7].
The Committee has assessed the health hazards from low-level electromagnetic fields generated by radio transmitters.

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