Recently, my favorite television show, Better Call Saul, came to a conclusion with its final episode. One of the main characters, Chuck McGill, portrayed by actor Michael McKean, is a successful attorney who believes that he suffers from electromagnetic hypersensitivity (EHS). Because of his imagined illness, Chuck lives a reclusive lifestyle as he cannot be anywhere near electricity, cell phones, or Wi-Fi. The problem is that healthcare professionals do not accept EHS as a medical condition. I don't want to spoil the TV show for anyone who has not seen it yet; however, Chuck's belief that he suffers from EHS is instead a mask for psychiatric illness.
So why am I writing about a TV show character? Well, it reminds me of all the misinformation rampant on the Internet and the media about possible adverse health effects from exposure to Wi-Fi. A simple Google search will reveal outlandish claims from so-called "experts" on this topic. If you believe what you read, the electromagnetic fields (EMFs) from Wi-Fi cause cancer and other diseases. And gentlemen, you had better remove the Wi-Fi router from your home because, evidently, long-term exposure to Wi-Fi is a proven root cause for male pattern baldness.
I thought about linking to some of the "Beware of the Wi-Fi" crackpot websites; however, I chose not to because I do not want to lend them any credibility. Very often, irresponsible journalists publish articles based on some of this nonsense. It's especially troubling when this discussion moves toward the possible negative health effects on children.
Of course, these claims are absurd. However, Wi-Fi networking vendors and their partners must battle this misinformation every year. For example, decision-makers at K-12 school systems often want documented proof that Wi-Fi is not harmful.
For many years, I have been asked to address these concerns about the adverse health effects of the exposure of humans to Wi-Fi radio waves. The good news is that the World Health Organization (WHO) and government agencies set standards that establish exposure limits to radio waves, with which radio frequency (RF) products must comply. Tests performed on wireless devices have shown that they operate substantially below the required safety limits set by these organizations. Most of the research on this topic is usually about the possible effects of RF generated by cell phones because people hold these devices to their heads. Although the rules vary, a cell phone's maximum transit power is typically double the maximum transmit power of an average indoor Wi-Fi access point.
In the United States, Federal Communications Commission (FCC) guidelines have established a minimum level of safe human exposure to radio frequency (RF) energy in wireless communications devices. Since 1996, the FCC has required that all wireless communications devices sold in the USA meet its minimum guidelines for safe human exposure to RF energy. For example, the FCC specifies exposure limits for wireless devices intended for use near or against the body in terms of a specific absorption rate (SAR), a measure of the rate at which RF energy is absorbed by the body. The FCC allows an SAR limit of 1.6 watts per kilogram (W/kg)-averaged over one gram of tissue-for exposure to wireless devices. More information can be found on the FCC website, where they address the health concerns of wireless devices:
“Some health and safety interest groups have interpreted certain reports to suggest that wireless device use may be linked to cancer and other illnesses, posing potentially greater risks for children than adults. While these assertions have gained increased public attention, currently no scientific evidence establishes a causal link between wireless device use and cancer or other illnesses.”
Additionally, the Wi-Fi Alliance states this about the same topic:
“A range of scientific research undertaken to-date concludes there is no evidence that low-power wireless networks pose health threats to users or to the general public.”
Let me try and put this conversation in simpler terms. Although rules and regulations vary per country, the average maximum transmit power of an indoor Wi-Fi access point is about 100 mW. Now add a three dBi gain antenna, and the amount of energy coming out of the tip of the AP’s antenna is 200 mW of power. By the way, for user density purposes, most indoor APs rarely use maximum transmit power, but I will use these numbers anyway.
So, what is the amount of power that passes through your body? Well, it really is all about physics. Any RF signal will attenuate as it passes through walls and other objects. Additionally, RF attenuates as a function of distance based on what is known as free space path loss (FSPL). As a matter of fact, a 2.4 GHz RF signal attenuates about 40 dB in the first meter it travels. An RF signal in the 5 GHz frequency band attenuates about 47 dB in the first meter it travels. Without getting too caught up in the math, a quality received signal for a Wi-Fi user device is about -70 dBm. This converts to one ten-millionth of 1 milliwatt. In other words, the average Wi-Fi signal passing through your body is in the millionths of 1 milliwatt. Sure, you could be standing directly underneath an AP mounted in the ceiling and receive a -40 dBm signal, which would mean that 1/10,000th of 1 milliwatt is now hitting you on the head. My point is that any exposure to Wi-Fi energy is meager.
But what about the long-term effects of exposure to Wi-Fi? I will use an analogy I stole from well-known Wi-Fi expert Keith Parsons. Suppose we place 10 Wi-Fi access points in a room where they all encircled a human being at a distance of 1 meter. The APs are all using maximum transmit power. How much time do you think it would take to cause harm due to exposure to Wi-Fi? Without getting too deep into the math, if any person could sit in that circle of APs for 75 years, the amount of exposure would be the equivalent of around 10 seconds of walking in the sunshine on a beach. Better break out the sunscreen before you turn on the Wi-Fi.
So, are there any resources that refute the erroneous claims of Wi-Fi making you sick? Yes, the Wi-Fi Alliance takes any concern about the alleged health impact of Wi-Fi technology seriously. They offer a brochure on the topic along with other links to independent studies.
Bottom line, you are not going to go bald because of Wi-Fi. I am however not sure about the effects of Wi-Fi on household pets. So just to be safe, I recommend this tin-foil hat for cats you can purchase from my favorite gag store, Archie McPhees.