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Wireless electronic devices and health

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  • 1. Wireless electronic devices and healthThe World Health Organization has acknowledged that electromagnetic fields (EMFs) areinfluencing the environment (but not people), and that some people are worried about possibleeffects.[1] In response to public concern, the World Health Organization established theInternational EMF Project in 1996 to assess the scientific evidence of possible health effects ofEMF in the frequency range from 0 to 300 GHz. They have stated that although extensiveresearch has been conducted into possible health effects of exposure to many parts of thefrequency spectrum, all reviews conducted so far have indicated that exposures are below thelimits recommended in the ICNIRP (1998) EMF guidelines, covering the full frequency rangefrom 0–300 GHz, and do not produce any known adverse health effect.[citation needed]International guidelines on exposure levels to microwave frequency EMFs such as ICNIRP limitthe power levels of wireless devices and it is uncommon for wireless devices to exceed theguidelines. These guidelines only take into account thermal effects, as nonthermal effects havenot been conclusively demonstrated.[2] The official stance of the Health Protection Agency isthat “[T]here is no consistent evidence to date that WiFi and WLANs adversely affect the healthof the general population”, but also that “...it is a sensible precautionary approach...to keep thesituation under ongoing review...”.[3]Exposure difference to mobile phonesUsers of wireless devices are typically exposed for much longer periods than for mobile phonesand the strength of wireless devices is not significantly less. Whereas a mobile phone can rangefrom 21 dBm (125 mW) for Power Class 4 to 33 dBm (2W) for Power class 1, a wireless routercan range from a typical 15 dBm (30 mW) strength to 27 dBm (500 mW) on the high end.[4]Wireless routers can be located significantly farther away from users heads than a mobile phone,resulting in far less exposure overall. The Health Protection Agency (HPA) claims that if aperson spends one year in a Wi-Fi hotspot, they will receive the same dose of radio waves as ifthey had made a 20-minute call on a mobile phone.[5] Nevertheless, the same is not true of Wi-Fi enabled laptops, which are not as far away.The HPA also acknowledges that due to the mobile phones adaptive power ability, a DECTcordless phones radiation could actually exceed the radiation of a mobile phone. The HPAexplains that while the DECT cordless phones radiation has an average output power of 10 mW,it is actually in the form of 100 bursts per second of 250 mW, a strength comparable to somemobile phones.[6]Wireless LANMost wireless LAN equipment is designed to work within predefined standards. Wireless accesspoints are also often close to humans, but the drop off in power over distance is fast, followingthe inverse-square law.[7] However, wireless laptops are typically used close to humans. WiFi
  • 2. has been anecdotally linked to electromagnetic hypersensitivity, e.g., in Toronto, Canadaschoolchildren as well as staff workers of France National Library.[8]The HPAs position is that “...radio frequency (RF) exposures from WiFi are likely to be lowerthan those from mobile phones.” It also saw “...no reason why schools and others should not useWiFi equipment.”[3] In October 2007, the HPA launched a new “systematic” study into theeffects of WiFi networks on behalf of the UK government, in order to calm fears that hadappeared in the media in a recent period up to that time".[9] Dr Michael Clark, of the HPA, sayspublished research on mobile phones and masts does not add up to an indictment of WiFi.[10]BluetoothBluetooth also uses the microwave frequency spectrum in the range of 2.4 GHz to 2.4835 GHz.The radiated output power of Bluetooth devices varies between 1 and 100 mW, and can operatecontinuously or sporadically (on demand), so total exposure to EMF radiation is quite variable.Bluetooth devices have not been linked with any health issues.Other devicesRadio frequency in the microwave and radio spectrum is used in a number of practical devicesfor professional and home use, such as:  DECT and other cordless phones operating at a wide range of frequencies  Remote control devices for opening gates, etc.  Portable two-way radio communication devices, such as walkie-talkies  Wireless security (alarm) systems  Wireless security video cameras  Radio links between buildings for data communication  Baby monitors  Smart meters for electric energyIn addition, electrical and electronic devices of all kinds emit EM fields around their workingcircuits, generated by oscillating currents. Humans are in daily contact with computers, videodisplay monitors, TV screens, microwave ovens, fluorescent lamps, electric motors of severalkinds (such as washing machines, kitchen appliances [like electric can openers, blenders, andmixers], water pumps, etc.) and many others. A study of bedroom exposure in 2009 showed thehighest ELF-EF from bedside lights and the highest ELF-MF from transformer devices, whilethe highest RF-ELF came from DECT cordless phones and outside cellphone base stations; allexposures were well below International Commission on Non-Ionizing Radiation Protection(ICNIRP) guideline levels.[11] The highest typical daily exposure, according to a study of 2009,came from cellphone base stations, cellphones and DECT cordless phones, with the highestexposure locations in trains, airports and buses.[12] The typical background power ofelectromagnetic fields in the home can vary from zero to 5 milliwatts per meter squared.[citationneeded] Long-time effects of these electromagnetic fields on human and animal health are stillunknown.
  • 3. Related Links:http://www.articlemayhem.com/Art/373180/32/The-right-mode-to-Turn-out-toward-be-a-Cisco-Licensed-Internetwork-Expert-Safety-CCIE-Safety.htmlhttp://article.chanderkamal.com/2011/09/pt-supplements-bodily-tools-through-permitting-ccna-students-to-make-networkshttp://www.articledirectoryzone.com/Art/58153/32/How-to-activate-routing-on-local-and-wide-area-networks-on-Windows-Server-2003.htmlhttp://alphaarticle.com/the-things-you-can-be-taught-in-the-ccna-research-information-intended-for-the-icnd2-examhttp://www.a2zarticlesdirectory.com/tag/bookhttp://duuuude.co.cc/2011/07/22/ccna-the-issues-are-the-capabilities-of-a-router-in-computinghttp://www.internet-marketing-cafe.com/Art/225483/31/The-Chances-Are-That-You-Should-Begin-Through-Your-CCNA.htmlhttp://www.articleintelligence.com/Art/142332/4/Natural-Remedies-for-Sinusitis.htmlhttp://www.dnnmodules.org/ccna-test-the-things-is-an-ip-address-extra-in-relation-to-ip-deal-withhttp://www.onlyarticles.com/ipv6-introduction-intended-for-ccna-larger-handle-space-and-options-of-ipv6http://www.go-see.info/Article/Boost-Your-Profession-via-Comptia-Certifications/617917http://www.onlyarticles.com/fb-google-be-part-of-on-the-website-future-warninghttp://www.allexpertarticles.com/computers/construct-up-ccna-home-lab-kits/93019http://webmasterarticles.net/ccna-one-issue-that-helped-build-up-meant-for-that-was-that-the-novell-exams-were-adaptivehttp://www.articlekingpro.com/Article/CCNA-Certification--What-is-an-IP-Address--More-Regarding-IP-Address/809149http://articles2win.com/computers/ccnp-is-of-the-top-paying-it-trainings-certifications-2011-portfoliohttp://www.dnnmodules.org/guide-toward-the-apache-http-server-computer-software
  • 4. http://shared4all.org/technology/ccna-exam-ip-handle-extra-iphttp://www.mcmcse.com/forums/viewtopic.php?p=86816http://www.go-see.info/Article/IPv6-Introduction-used-for-CCNA--Bigger-tackle-house-and-Options-of-IPv6/767291http://article2008.com/Art/682903/265/What-You-Can-Learn-In-Cisco-Press-Ccna-Examine-Guide-In-favor-of-Icnd1.htmlhttp://menamark.com/index.php?page=article&article_id=12483http://www.articlesbase.com/computers-articles/how-to-change-the-preference-levels-for-routing-sources-4180941.htmlhttp://www.hotarticlesonline.com/2011/07/how-toward-improve-networks-for-business-worldhttp://www.onlyarticles.com/guide-to-the-apache-http-server-software-packagehttp://www.bizshark.com/directory?l=N&p=7http://www.onlyarticles.com/4-tips-to-assessment-a-ccna-study-information-completelyhttp://www.articlesbase.com/networks-articles/how-to-add-a-routing-interface-to-your-windows-2003-server-4150161.htmlhttp://menamark.com/index.php?page=article&article_id=40526http://directory-software.com/index.php?page=article&article_id=27394