Many portable meters are now available to measure electromagnetic fields and electromagnetic radiation emitted by wireless technology, power lines, computers, etc. and we are often asked to recommend meters for those interested in monitoring their own home and workplace environment.
What some people don’t realize is that a meter that measures the radiation from Wi-Fi is not the same meter you use to measure the magnetic field near power lines. So the first question is what do you want to measure? Here are the options for what we now call “electrosmog”.
This is the radiation generated by wireless technology such as Wi-Fi routers, cell phones, iPads, iPods, smart watches and other wearables, cordless phones, wireless baby monitors, some home security systems, smart meters, cell phone base stations, TV and radio broadcast antennas, and radar antennas.
These are two different fields (electric and magnetic) and are generated by anything that plugs into an electric outlet and uses electricity. Some appliances produce high magnetic fields (based on the current they are consuming) while others produce lower magnetic fields. Magnetic fields are generated whenever an appliance is turned on. An electric field is generated when an appliance is plugged into an electric outlet. So a lamp plugged into the wall socket has an electric field associated with it all the time (on or off) and a magnetic field only when it is turned on. The main sources of ELF (extremely low frequency) electric and magnetic fields inside a home include appliances and wiring. Sometimes metal plumbing may be surround by an electromagnetic field because of the grounding system we use in North America. People who live near power lines, substations or transformers may be exposed to higher electric and magnetic fields. Electric fields are shielded by building material but magnetic fields are difficult to shield and these penetrate windows and walls. Ideally both the electric field and magnetic field need to be tested for those concerned about their exposure.
Intermediate frequencies often called harmonics or transients, are generated by electronic devices, switch mode power supplies, rheostats, arching and are commonly produced by energy efficient devices. These intermediate frequencies produce poor power quality, commonly referred to as “dirty electricity.” They are known to adversely affect sensitive electronic equipment, so most people use power surge protectors for their computers and entertainment units. Power conditioners are also available to improve power quality and are often used by audiophiles.
These are the common types of electrosmog in a rural and urban environment that can be easily measured with minimal training. Another type, ground current and/or contact current, is more difficult to measure and is not discussed here.
All types of electrosmog exposure mentioned above (low frequency electric fields; low frequency magnetic fields; dirty electricity; and radio frequency radiation) have documented biological effects and should be kept as low as possible especially in areas where people spend hours each day. Children, pregnant women, people with a family history of cancer or miscarriages; and those with a compromised immune system may be particularly vulnerable.
When electricity was first distributed in North America, the frequency was set at 25 Hz (or 25 cycles per second). Many people could detect this light flicker and it caused headaches and eye strain. Incandescent lights tend not to flicker to any great degree. However, energy efficient light bulbs produce considerable flicker and are making people ill. This flicker or light “noise” occurs at thousands of cycles per second and is not detectable by the eyes but is detected by other parts of the body. Not only do energy efficient light bulbs “flicker” but so do SOME TV screens and computer screens. Dimming incandescent light bulbs also produces a flicker unless you have a three-way light bulb for dimming. In contrast, neither the sun nor candles produce this light flicker and so this flicker is not normal. Fortunately we are now able to measure flicker in light sources. See “light bee” below. Ideally you want to use light bulbs, computer screens, TV monitors as well as cell phones and tablets with the least amount of flicker possible.
This is a difficult question to answer. In areas where you might spend several hours daily (bedroom, office, kitchen, school) you want the levels to be as low as possible and ideally less than the following:
ELF magnetic fields less than 1 mG; ELF electric fields less than 5 V/m; radio frequency radiation in sleeping spaces of less than 10 micro W/m2 (or less than 0.001 microW/cm2); and dirty electricity less than 30 GS units; Light flicker, as little as possible. Please note these are the values that we recommend based on the literature showing potentially harmful effects above these values. They are well below existing guidelines in most countries. Higher levels of exposure for short periods are unlikely to be harmful except perhaps to those who have already developed a sensitivity to these frequencies.
Click here for specific meter recommendations by Dr. Magda Havas pdf.