Hi Delon,
This is an excellent question, that most of us have asked at one point.
The consensus that I have gathered is that 10-12 feet is a reasonable distance. There is much conflicting information regarding the Health effects of "Wireless". It is good to be well versed on the subject and to realize that the bottom line, truly, is that this had not been studied for a long enough time frame for anyone to know the absolute truth. Here are some good example Pro/Con type articles;
"There is currently insufficient scientific basis for concluding either that wireless communication technologies are safe or that they pose a risk to millions of users.... FCC radio frequency radiation guidelines are based on protection from acute injury from thermal effects of RFR exposure and may not be protective against any non-thermal effects of chronic exposures."
U.S. Food and Drug Administration, February 2000
http://www.energyfields.org/science.html
Cisco Aironet 1200 Series
Wireless Systems and RF Safety Issues
This document discusses the results of research into the possible health effects of RF devices.
http://www.cisco.com/en/US/products/hw/wireless/ps430/products_white_paper09186a0080088791.shtml
All Cisco and Linksys wireless products are evaluated to ensure that they conform to the RF emissions safety limits adopted by agencies in the United States and around the world. These evaluations are in accordance with the various regulations and guidelines adopted or recommended by the Federal Communications Commission (FCC)* and other worldwide agencies**.
World Health Organization - Electromagnetic fields and public health
http://www.who.int/mediacentre/factsheets/fs304/en/index.html
Canadian university says no to WiFi over health concerns
http://arstechnica.com/news.ars/post/20060222-6235.html
Health fears lead schools to dismantle wireless networks
http://www.timesonline.co.uk/tol/life_and_style/education/article642575.ece
Low-Power Wireless Devices Pose No Known Health Risk
Do low-power wireless devices such as WLAN client cards, access points, or RFID tags pose a health threat? Available evidence today suggests that there is no clear correlation between low-power wireless use and health issues.
Recent studies strongly suggest that the use of cellular telephone equipment does not create health risks. Two important recent studies that reached this conclusion are:
• A report written by Dr. John D. Boice, Jr. and Dr. Joseph K. McLaughlin of the International Epidemiology Institute in the United States in September 2002 for the Swedish Radiation Protection Authority.
• A report to the European Commission from the Scientific Committee on Toxicity, Ecotoxicity, and the Environment, titled "Opinion on Possible Effects of Electromagnetic Fields, Radio Frequency Fields, and Microwave Radiation on Human Health."
Few studies deal directly with the affects of WLAN devices. The emission levels of WLAN and RFID tags are below RF emission levels from typical cellular telephones. Therefore, any conclusions relating to the safety of cellular telephone equipment can almost certainly be applied to WLAN or RFID devices**.
The RF emission levels from a typical WLAN are well within the safety emission level thresholds set by the World Health Organization (WHO)***
http://www.cisco.com/en/US/prod/collateral/wireless/ps5678/ps430/ps4076/prod_white_paper09186a0080088791_tk809_TSD_Technologies_White_Paper.html
This has links to quite a few interesting articles;
http://omega.twoday.net/stories/1122031/
This "clip" is very much applicable here;
'The research hasn't been done - we cannot assume that wireless networks have no effects', expert warns
http://www.independent.co.uk/life-style/health-and-wellbeing/health-news/scientists-demand-inquiry-over-wifi-446695.html
Hope this helps!
Rob
