Wi-Fi has become the fourth utility we need - after water, gas, and electricity. Everything is being "wifized." My watch, my phone, my TV, my iPad, my DVD player, my coffee maker, my refrigerator, my weighing machine! Schools, hospitals, businesses, coffee shops… it's everywhere. We can’t live without it, but hopefully it is not killing us slowly. I say this because FCC guidelines for maximum allowed transmit power of Wi-Fi Access Points are based on the assumption that Wi-Fi signals are received by a human body from a distance for one transmitting Wi-Fi antenna. However, we are not exposed to just one transmitting Wi-Fi antenna anymore.
From the FCC.gov site:
"Since 1996, the FCC has required that all wireless communications devices sold in the United States meet its minimum guidelines for safe human exposure to radio frequency (RF) energy. The FCC’s guidelines and rules regarding RF exposure are based upon standards developed by IEEE and NCRP and input from other federal agencies. These guidelines specify exposure limits for hand-held wireless devices in terms of the Specific Absorption Rate (SAR). The SAR is a measure of the rate that RF energy is absorbed by the body. For exposure to RF energy from wireless devices, the allowable FCC SAR limit is 1.6 watts per kilogram (W/kg), as averaged over one gram of tissue. All wireless devices sold in the U.S. go through a formal FCC approval process to ensure that they do not exceed the maximum allowable SAR level when operating at the device’s highest possible power level."
This is where the problem is. The amount of radiation exposure today is over 100 times higher as we live in proximity to a very large number of actively transmitting Wi-Fi Devices and Wi-Fi Access Points/Routers. Consider the reality today:
Each person today carries three to five Wi-Fi devices (phone, laptop, watch, tablet, to name a few). And, the last time I looked for a Wi-Fi network at my home, I could see over 10 Wi-Fi Access Points (neighbors!).
When I am at the coffee shop, not only do I see multiple SSIDs, there are over 15 to 20 people working on their iPads and laptops (each device actively transmitting Wi-Fi).
Today’s SCHOOLS initiative for online classrooms is a scenario that will involve about 20 to 25 iPads actively transmitting per classroom and in multiple adjacent classrooms. Schools also have one to three Wi-Fi Access Points per classroom and additional Access Points in hallways, etc. Whether you are a student or teacher, you may see over 40 Wi-Fi Antenna and 200 clients in Wi-Fi proximity.
Enterprises deploy a large number of access points for better experience for roaming and other applications. For example, a typical 100-employee office might have over 30 Wi-Fi Antenna and over 300 Wi-Fi devices.
When I am in hospital, the phones carried by nurses, the code red buttons, the IV pumps are all Wi-Fi-connected. Whether a new-born baby, child, or a senior citizen, they are all getting exposed to Wi-Fi even if they are not using it.
At a retail store, they have a large number of Access Points and Wi-Fi devices. A typical Walmart-type store might have around 50 Access Points and 600 Wi-Fi devices, such as bar-code scanners, price verifiers, phones etc., carried by visitors and employees.
Each Access Points contains 1 to 12 Radios, and each radio has multiple transmitting antennas.
And the exposure to RF energy from one wireless device itself is close to the allowable FCC SAR limit already. For example:
- iPhone's published SAR (specific absorption rate): 1.18 W/kg Body and 1.25 W/Kg Head.
- iPad's published SAR (specific absorption rate): 1.19 W/kg Body.
This is why I am concerned. All focus has been only on SAR and safety, with respect to cellular. However, in real-life measurement, the signals sent from Wi-Fi are more continual than on 3G transmission, and the effect is aggregate. The peak Wi-Fi radiation for iPads, Laptops, and Wi-Fi Antenna in aggregate is much higher.
About 300 of every 100,000 people develop cancer in top-10 countries with populations around 5 million or more (Denmark, France, Australia, Belgium, Norway, United States of America, Ireland, South Korea, Netherlands, and Canada), and these countries also have very high internet/Wi-Fi penetration (Denmark: 96%, France: 86%, Australia: 89%, Belgium: 85%, Norway: 96%, U.S.: 87%, Ireland: 82%, South Korea: 92%, Netherlands: 96%, Canada: 93%). The correlation is very hard to establish, as multiple factors are involved. However, with the increase of Wi-Fi/Radiation exposure today, the limits established before the "wifization" of society may not be good enough.
I strongly believe that the time has come to re-evaluate the FCC guidelines, as well as how Wi-Fi transmit power is handled by Wi-Fi device/Access Point vendors. Here are some suggestions on how to do so:
FCC regulations need to be updated based on the maximum power of each transmitting device based on number of Wi-Fi Transmitting antenna in proximity.
Schools and businesses should require all Wi-Fi devices (client devices and Wi-Fi Access Point/Routers) to do automatic maximum power selection/reduction based on the number of Wi-Fi Transmitting antennas in proximity.
Access Point deployments and power settings should be done with consideration around aggregate SAR value exposure.
Lets build our future using Wi-Fi, and protect our future at the same time.
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