For this topic I think a Wi-Fi vendors input is actually extremely valuable as we tend to see a lot more discussion on this topic than any individual organization. We (all vendors) continue to address this topic innumerable times from worldwide concerns.
Some background: On May 31, 2011, the International Agency for Research on Cancer released the following: "The WHO/International Agency for Research on Cancer (IARC) has classified radiofrequency electromagnetic fields as possibly carcinogenic to humans (Group 2B), based on an increased risk for glicoma, a malignant type of brain cancer, associated with wireless phone use." Link: http://www.iarc.fr/en/media-centre/pr/2011/pdfs/pr208_E.pdf Since release of that document multiple organization, both private and governmental have performed hundreds of 'studies' and with just a little bit of research you can find a study to confirm your own specific beliefs. To this day I have yet to see any conclusive analysis/report that confirms or invalidates the health threat, however as we all know it is impossible to prove a negative (I.e. - Wi-Fi is not a possible threat). A key point of the report, often overlooked is that radiofrequency electromagnetic fields were classified as 2B - possibly carcinogenic to humans. The 2B classification identifies ~300 other products/activities and includes coffee, pickled vegetables, firemen, etc. I do not mean to make light of carcinogenic concerns, however it is important to understand what a rating of 2B implies. - http://monographs.iarc.fr/ENG/Classification/ClassificationsGroupOrder.pdf Technical thoughts: Wi-Fi is a low power technology; an RSSI value of -65 means a power level of only ~ millionth of a watt - http://www.moonblinkwifi.com/dbm_to_watt_conversion.cfm Many other common technologies, including cell phones are of much greater power and closer to the individual, in fact that was the focus of the study Note- the 802.11 standard does not define any relationship between RSSI value and power level in mW or dBm. Vendors and chipset makers provide their own accuracy, granularity, and range for the actual power (measured as mW or dBm) and their range of RSSI values. (Wikipedia) RF Comparison between Cell and Wi-Fi service (varies by products) Characteristic Cell Phone Wi-Fi Client Wi-Fi AP User distance from radio In contact 0.3 meters 3-30 meters Transmit power levels Up to 2 Watts Up to 40 mW Up to 100 mW / radio Transmit duty cycle Constant Intermittent Intermittent per radio Additionally as mentioned by another respondent the RF 'threat' in any specific area by Wi-Fi probably pales compared to the cellular, Bluetooth, microwaves, power lines, ... in the same area. Disabling the AP in the cafeteria will do nothing about the hundreds of clients that will generate even more probe traffic (high power/low data rate) and cellular traffic. Medical Thoughts: This is touchier topic as the reports are all over the place and there is a significant emotional impact here. There was one school that performed a study with their students and identified more health problems on school days than weekends. Problem with that study is I recall the same thing when I went to school, at that time we didn't have Wi-Fi, cell phones or even calculators (abacus generated no RF energy), so this demonstrates that you can 'validate' your own belief if you look hard enough. I also agree with an earlier respondent who implies that hiding the AP or disabling the light may serve a placebo effect. Final thought, everyone is different and as sulfur and penicillin are wonder drugs to some, they are also potentially fatal to others. I believe it is possible some individuals are more sensitive to RF energy than others, however if that is the case I personally believe the potential threat from Wi-Fi signals is far less than other RF technologies. As for how to deal with students/staff/parents on this topic can be difficult as their concerns may be very real to them. The first question I would ask is if they use cell phones, cordless phones and microwave ovens, etc. If the answer is yes than chances are Wi-Fi is probably not as big a problem as they think. But no black and white answers here. For more information: As mentioned above there is tons of reports out there, I recommend the following as a starting place Wi-Fi Alliance Information http://www.wi-fi.org/knowledge-center/articles/wi-fi-and-health http://www.wi-fi.org/files/kc/Wi-Fi_Health_Brochure_2011.pdf World health Organization (WHO) Information http://www.who.int/mediacentre/factsheets/fs193/en/index.html An Interesting Article - "It has been estimated that you get a bigger dose of microwaves from one 20-minute phone call than from a year's Wi-Fi." http://www.theguardian.com/technology/askjack/2012/sep/27/wi-fi-health-risks Perry Perry Correll Principal Technologist 805 376 5437 office | 321 505 7726 mobile xirrus.com | twitter.com/xirrus | facebook.com/xirrus [cid:[email protected]] [cid:[email protected]] If you received this message in error, the information in or attached may be confidential or privileged, so please delete it and contact the sender. We appreciate your trust and good judgment and pledge to show you the same in return. Please consider the environment before printing this email. From: The EDUCAUSE Wireless Issues Constituent Group Listserv [mailto:[email protected]] On Behalf Of Danny Eaton Sent: Sunday, September 01, 2013 7:54 AM To: [email protected]<mailto:[email protected]> Subject: Re: [WIRELESS-LAN] Sickness for rf (802.11) I usually try to talk with the student, understand what their concerns are, and at the very least, turn the light off. I did move one ap to a different location from the bedroom to a common room. Connected by Motorola Walter Reynolds <[email protected]<mailto:[email protected]>> wrote: So if you get these requests, how do you handle them? Shutting down the AP in a users room is obviously going to affect overall coverage for other rooms. ------------------------ Walter Reynolds Principal Systems Security Development Engineer Information and Technology Services University of Michigan (734) 615-9438 On Sat, Aug 31, 2013 at 12:29 PM, Danny Eaton <[email protected]<mailto:[email protected]>> wrote: Yes. We've had a few requests to turn them off in student rooms, but overall not many. No doctor notes, yet. Connected by Motorola "Hurt,Trenton W." <[email protected]<mailto:[email protected]>> wrote: So I had to turn off aps for a person on my campus for areas they where visiting due to rf sickness. They provided a dr note too.. Has anyone every had a request for something like this? 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