Suffield Academy WLAN Exposure Policy

In 2014 Suffield Academy upgraded it's wireless network to cover nearly all indoor spaces (including dormitories, classrooms, and shared public spaces). This expansion brought the school in line with the wireless installations available at many other residential high schools and most colleges and universities. We are aware that some residents may have concerns regarding the radio signals emitted by the equipment, especially in living spaces. This page explains the school's official policy on such issues.

Suffield Academy is confident that the technology used for the school's wireless network is safe and does not pose a health risk to individuals on the campus. The location, configuration, and device count of wireless equipment have been selected to provide the best reception and signal quality. Thus, the school's policy is to not alter the location, power, or configuration of any installed equipment in response to user requests.

Please read on for additional information if you continue to have concerns or wish to contact us regarding this policy.

This page was last updated at 1:08 PM on July 6, 2020.

Electromagnetic fields (EMF for short) are created by many different types of technology and natural phenomena. These fields vary in frequency and strength. It's important to note that there exists a very wide range of EMF frequencies; to name a few: television and radio broadcasts, wireless networking, visible light, ultraviolet radiation, X-rays, and gamma rays. Note that some types (e.g., visible light) are not harmful, but others (X-rays) can be. Thus, the term "EMF" by itself does not denote safety or hazard.

The frequency of electromagnetic radiation is directly related to its energy: higher frequencies carry more energy. Radiation above a certain frequency/energy level is called "ionizing", and is what people usually think of when they hear "radiation". X-rays are an example of ionizing ration, as they can cause cancer and other damage in high doses. At lower frequencies we have "non-ionizing" radiation. This type of radiation can heat things up (like space heaters or microwave ovens) and cause other effects, but lacks the energy to break atoms apart. Television and radio signals, mobile phone connections, and wireless network signals fall into this category.

In addition to the frequency, a person's exposure to radiation is determined by:

• The duration of the exposure. As common sense would dictate, the longer you are exposed to a source of radiation, the more you will absorb.
• The proximity to the source. Note that radiation follows the inverse-square law, meaning that increasing the distance from the source results in an exponential drop in the amount of radiation absorbed. As an example, if you absorb 1000 units of radiation at a distance of 1 meter from the source, moving an additional meter away results in a dose of only 250 units (doubling the distance results in a quarter of the radiation). Doubling the distance again to 4 meters would result in a dose of 62 units (a sixteenth of the original dose). Thus, even small increases in distance can result in a dramatic decrease in the amount of radiation exposure.
• The power associated with the radiation. Think of this as the rating on a light bulb. A 60-Watt bulb does not produce as much radiation (light) as a 100-Watt bulb.

The wireless networks at Suffield Academy operate in the 2.4 GHz and 5 GHz frequency ranges. This is in the "microwave" range, which has a shorter wavelength (i.e., is more energetic) than television and radio signals, but has a longer wavelength (i.e., is less energetic) than visible light, UV, and X-rays. It is non-ionizing.

Though some of these frequencies are the same as those used in microwave ovens, the power of the signals from WLAN equipment is very low: 500mW at maximum, or half of a Watt. A typical microwave oven operates at 1,000 Watts or more. Additionally, this power rating is less than that of a mobile phone placing a call, or baby monitors and other common electronics in the home.

Because of the non-ionizing radiation and relatively low power, WLAN signals should not pose a health risk. The World Health Organization has published a fact sheet regarding wireless networking [1] with detailed information outlining the safety of such signals. Additionally, the WHO states that non-ionizing radiation exposure within the guidelines established by the International Commission on Non-Ionizing Radiation Protection [2] should not pose any significant risks. WLAN signals fall well within the guidelines (only reaching 2% of the recommended limits).

Some people have reported a "sensitivity" to EMF, but such sensitivities have not be validated scientifically. We follow the conclusions of the WHO [4] stating that no scientific basis exists linking such sensitivity to actual EMF exposure, and do not believe that our networks cause health issues of this nature.

Is there cause for concern when people are exposed to WLAN radiation over a long period of time (many hours per day, every day)?

In short, no. WLAN radiation is already non-ionizing, and so doesn't carry significant risk. Additionally, the transmission power of these signals is very low compared to other sources:

• International guidelines recommend a maximum field strength of 61 V/m [2]. WLAN is 3.9 V/m when 20cm from an access point, and 1.1 V/m when 1m away from an access point (with a continued exponential drop-off as distance increases). WLAN broadcasts are well within accepted safety limits.
• Other commonly-used devices can produce higher-intensity fields, but are still regarded as safe. For example, baby monitors can output 8.5 V/m at 20cm and 3.2 V/m at 1m [3], yet they are often left on for extended periods of time near children.
• The United Kingdom government's Health Protection Agency estimated that spending a year near a WLAN hot spot results in the same absorbed dose of radio waves as making a 20-minute cell phone call [5].

What about studies showing health risks for cell phones?

You may have read media reports of cell phone links to cancer, or even the WHO's IARC committee reports that list cell phones as a "Class 2B Carcinogen". Note that there are other common items that have received the same classification (pickled vegetables and coffee, to name two). Scientists have rated the media's response as overblown [6].

However, even if we assume that cell phones carry a legitimate risk, WLAN exposure carries far less risk than cell phones. The maximum transmission power of cell phones is greater than that of WLAN equipment. Additionally, cell phones are typically much closer to (or even touching) the head and body, where WLAN equipment is further away. Radiation exposure follows the inverse square law, meaning that the reduction in exposure is related to the square of the distance from the source. To use a real-world example, a phone 1m away from your body exposes you to 10,000 times less radiation than a phone held 1cm away (directly against the body).

Even if we assume that cell phones carry some legitimate risk, the reduced power and increased distance of WLAN equipment makes the relative risk vanishingly small. Given that the risk of cell phones has not been conclusively determined, we have confidence that WLANs are not of any concern.

What about people who are sensitive to WLAN radiation?

There have been several stories about people who have gotten sick from exposure to WLAN signals, and the term electromagnetic hypersensitivity [4] has been created to label these symptoms. Many websites have sprung up claiming that WLAN radiation is dangerous [7], feeding on the public's uncertainty about these topics.

To date, there have been no scientific studies (using proper controls and observing conditions) that demonstrate a link between the described symptoms and EMF. Additionally, sites selling products to "protect" people from the supposed dangers of EMF typically use a lot of jargon (and not a lot of specifics) to sell their products.

We've provided full references from established and well-respected sources to make our claims. We are confident that science supports our position and that there are no established health risks from WLAN radiation.

Whom should I contact if I have further questions?

If after reading this document you still have questions or concerns, please contact Jason Healy (the Director of Technology) via e-mail: jason@suffieldacademy.org.

1. Base stations and wireless technologies (EMF fact sheet from the World Health Organization).
2. ICNIRP Guidelines for limiting exposure to time-varying electric, magnetic, and electromagnetic fields (up to 300 GHz). Published in Heath Physics 74 (4):494‐522; 1998. See Table 7 (page 511/19).
3. IARC Monograph 102 (Non-ionizing radiation, Part 2: Radiofrequency electromagnetic fields, volume 102). Published by the International Agency for Research on Cancer, World Health Organization.
4. Electromagnetic hypersensitivity (EMF fact sheet from the World Health Organization).
5. Wi-fi health fears are 'unproven'. BBC News (BBC). 2007-05-21.
6. Cell phones are as carcinogenic as coffee. Gopala Kovvali, published in the Journal of Carcinogenesis (J Carcinog. 2001; 10: 18). Published online July 19, 2011. doi: 10.4103/1477-3163.83044
7. http://www.safespaceprotection.com/electrostress-from-wireless-routers.aspx (must cut and paste link)