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Encyclopedia > Electromagnetic radiation hazard

Electromagnetic radiation can be classified into ionizing radiation and non-ionizing radiation, based on whether it is capable of ionizing atoms and breaking chemical bonds. Ultraviolet and higher frequencies, such as X-rays or gamma rays are ionizing. These pose their own special hazards: see radiation and radiation poisoning. It has been suggested that this article or section be merged with light. ... Ionization is the physical process of converting an atom or molecule into an ion by changing the difference between the number of protons and electrons. ... A chemical bond is the physical process responsible for the attractive interactions between atoms and molecules, and that which confers stability to diatomic and polyatomic chemical compounds. ... UV redirects here. ... In the NATO phonetic alphabet, X-ray represents the letter X. An X-ray picture (radiograph) taken by Röntgen An X-ray is a form of electromagnetic radiation with a wavelength approximately in the range of 5 pm to 10 nanometers (corresponding to frequencies in the range 30 PHz... This article is about electromagnetic radiation. ... Radiation as used in physics, is energy in the form of waves or particles. ... Radiation Hazard symbol. ...


Non-ionizing radiation, discussed here, is associated with two major potential hazards: electrical and biological. Additionally, induced electric current caused by radiation can generate sparks and create a fire or explosive hazard. Electromagnetic induction is the production of an electrical potential difference (or voltage) across a conductor situated in a changing magnetic flux. ...

Contents

Electrical hazards

The oscillating electric and magnetic fields in electromagnetic radiation will induce an electric current in any conductor through which it passes. Strong radiation can induce current capable of delivering an electric shock to persons or animals. It can also overload and destroy electrical equipment. The electromagnetic field is a physical field that is produced by electrically charged objects and which affects the behaviour of charged objects in the vicinity of the field. ... Electric current is the flow (movement) of electric charge. ...


Fire Hazards

Extremely high power electromagnetic radiation can cause electric currents strong enough to create sparks. These sparks can then ignite flammable materials or gases, possibly leading to an explosion. This can be a particular hazard in the vicinity of explosives or pyrotechnics, since an electrical overload might ignite them. This risk is commonly referred to as RadHaz or HERO (Hazards of Electromagnetic Radiation to Ordnance). This article is concerned solely with chemical explosives. ... Pyrotechnics is a field of study often thought synonymous with the manufacture of fireworks, but more accurately it has a wider scope that includes items for military and industrial uses. ...


Biological hazards of EMF

The best understood biological effect of electromagnetic fields is to cause dielectric heating. For example, touching an antenna while a transmitter is in operation can cause severe burns[citation needed]. Birds sitting on very high-power antennas when transmission begins can be instantly cooked by RF energy[citation needed]. In fact, that is the principle behind the operation of a microwave oven. A yagi antenna Most simply, an antenna is an electronic component designed to send or receive radio waves. ... Antenna tower of Crystal Palace transmitter, London A transmitter (sometimes abbreviated XMTR) is an electronic device which with the aid of an antenna propagates an electromagnetic signal such as radio, television, or other telecommunications. ... It has been suggested that this article or section be merged with Radio waves. ... It has been suggested that this article be split into articles entitled Microwave oven and Microwave heating. ...


This heating effect varies with the frequency of the electromagnetic energy. The eyes are particularly vulnerable to RF energy in the microwave range, and prolonged exposure to microwaves can lead to cataracts. Each frequency in the electromagnetic spectrum is absorbed by living tissue at a different rate, called the specific absorption rate or SAR, which has units of watts per kilogram (W/kg). The IEEE and many national governments have established safety limits for exposure to various frequencies of electromagnetic energy based on SAR. FreQuency is a music video game developed by Harmonix and published by SCEI. It was released in November 2001. ... Microwaves are electromagnetic waves with wavelengths longer than those of terahertz (THz) frequencies, but relatively short for radio waves. ... Cataract is also used to mean a waterfall or where the flow of a river changes dramatically. ... Legend γ = Gamma rays HX = Hard X-rays SX = Soft X-Rays EUV = Extreme ultraviolet NUV = Near ultraviolet Visible light NIR = Near infrared MIR = Moderate infrared FIR = Far infrared Radio waves EHF = Extremely high frequency (Microwaves) SHF = Super high frequency (Microwaves) UHF = Ultra high frequency VHF = Very high frequency HF = High... Specific Absorption Rate (SAR) is a measure of the rate at which radio frequency (RF) energy is absorbed by the body when exposed to radio-frequency electromagnetic field. ... The Institute of Electrical and Electronics Engineers or IEEE (pronounced as eye-triple-ee) is an international non-profit, professional organization incorporated in the State of New York, United States. ...


There is also a body of evidence which supports the existence of complex biological effects of weaker non-thermal electromagnetic fields (see Bioelectromagnetics), including weak ELF magnetic fields and modulated RF and microwave fields. The theoretical mechanism of action of non-thermal electromagnetic fields is not fully understood, but there are some established biological effects for ELF. [1] [2] Because the extent of Non-thermal effects is not fully established, they may be beneficial or harmful. A common position presented regarding these effects is that, since they are not well understood, a precautionary principle approach would suggest minimizing exposure whenever possible. However, it should be recognized that the claims of biological hazards from low-energy electromagnetic radios (e.g. from mobile phones) are considered controversial[citation needed]. Bioelectromagnetics is the study of how electromagnetic fields interact with and influence biological processes. ... The precautionary principle is a moral and political principle which states that if an action or policy might cause severe or irreversible harm to the public, in the absence of a scientific consensus that harm would not ensue, the burden of proof falls on those who would advocate taking the...


Some studies have even suggested that a small percentage of the population may be electromagnetically sensitive and can physically react to very low level fields even in double-blind experiments, such as participants withdrawing from background levels in the 2006 Rubin study[3]. It does not seem to be a congenital condition and theories have been put forth that some form of external trigger such as previous chemical exposure may bring about this electrical sensitivity (ES)[4]. The double blind is ray charles is ray charlesis ray charlesis ray charlesis ray charlesis ray charlesis ray charlesis ray charlesis ray charlesis ray charlesis ray charlesis ray charlesis ray charlesis ray charlesis ray charlesis ray charlesis ray charlesis ray charlesis ray charlesof the scientific method, used to prevent research... Electrical sensitivity (ES), sometimes also called electrosensitivity or electromagnetic hypersensitivity (EHS), is a condition in which a person reports physical and / or psychological symptoms which appear to be aggravated by electric or magnetic fields or other electromagnetic waves at exposure levels tolerated by the general public. ...


However, the 2006 Rubin study concluded that "No evidence was found to indicate that people with self reported sensitivity to mobile phone signals are able to detect such signals or that they react to them with increased symptom severity. As sham exposure was sufficient to trigger severe symptoms in some participants, psychological factors may have an important role in causing this condition." It is important to note that the sham was also emitting RF radiation at a lower level, and that the reaction of participants to the sham exposure may also be related to EMFs [5]


U.S. military definition

In Federal Standard 1037C, the United States government adopts the following definition: Federal Standard 1037C, entitled Telecommunications: Glossary of Telecommunication Terms is a United States Federal Standard, issued by the General Services Administration pursuant to the Federal Property and Administrative Services Act of 1949, as amended. ...

Electromagnetic radiation hazards (RADHAZ or EMR hazards): Hazards caused by a transmitter/antenna installation that generates electromagnetic radiation in the vicinity of ordnance, personnel, or fueling operations in excess of established safe levels or increases the existing levels to a hazardous level; or a personnel, fueling, or ordnance installation located in an area that is illuminated by electromagnetic radiation at a level that is hazardous to the planned operations or occupancy. These hazards will exist when an electromagnetic field of sufficient intensity is generated to: (a) induce or otherwise couple currents and/or voltages of magnitudes large enough to initiate electroexplosive devices or other sensitive explosive components of weapon systems, ordnance, or explosive devices; (b) cause harmful or injurious effects to humans and wildlife; (c) create sparks having sufficient magnitude to ignite flammable mixtures of materials that must be handled in the affected area.

Department of Defense Dictionary of Military and Associated Terms It has been suggested that this article or section be merged with light. ... The magnitude of an electric field surrounding two equally charged (repelling) particles. ... In physics, intensity is a measure of the time-averaged energy flux. ... The Department of Defense Dictionary of Military and Associated Terms is a compedium of terminology used by the United States Department of Defense (DOD). ...


See also

Electromagnetism is the physics of the electromagnetic field: a field which exerts a force on particles that possess the property of electric charge and magnetic charge, and is in turn affected by the presence and motion of those particles. ... A Greenfield-type tower used in base stations for mobile telephony A mobile phone (Samsung) Mobile phone radiation and health concerns have been raised, especially following the enormous increase in the use of wireless mobile telephony throughout the world (as of August 2005, there were more than 2 billion users... For mobile phones see Mobile phone radiation and health With the focus on health concerns of mobile phones, people are also beginning to question the health risks of other wireless devices now being increasingly used at work and in the home, such as wireless local area networks, wireless phones, Bluetooth... Specific Absorption Rate (SAR) is a measure of the rate at which radio frequency (RF) energy is absorbed by the body when exposed to radio-frequency electromagnetic field. ...

External links

  • [6] World Health Organization information page on electromagnetic fields.
  • The Dangers Of Electro Magnetic Radiation (EMF)

  Results from FactBites:
 
Encyclopedia: Electromagnetic radiation hazard (458 words)
Electromagnetic radiation is a combination of oscillating electric and magnetic fields propagating through space and carrying energy from one place to another.
Klystrons give off both ionizing radiation in the form of X-rays and non-ionizing radiation in the form of radio and microwave, all of which are forms of electromagnetic radiation.
EM radiation with a wavelength between 400 nm and 700 nm is detected by the human eye and perceived as visible light.
Electromagnetic radiation hazard - Wikipedia, the free encyclopedia (558 words)
Additionally, induced current caused by radiation is a significant danger in the handling of electrically initiated explosives or pyrotechnics.
This risk is commonly reffered to as RadHaz or HERO (Hazards of Electromagnetic Radiation to Ordnance).
Each frequency in the electromagnetic spectrum is absorbed by living tissue at a different rate, called the specific absorption rate or SAR, which has units of watts per kilogram (W/kg).
  More results at FactBites »


 
 

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