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Electromagnetic Fields or “EMF”

Electromagnetic fields, both naturally occurring and human-made, are present throughout our environment. Because electromagnetic fields are ever-present, their sources and effects have been the subject of extensive study and scientific research.

Table of Contents

What is EMF?

Electromagnetic fields (EMF) are a combination of electric and magnetic fields.

Electric fields come from electricity, such as when a kitchen appliance is plugged in. Trees, walls, and most objects can block or weaken electric fields. 

Magnetic fields come from flowing electricity, such as when the appliance is turned on. Power lines produce magnetic fields continuously because current is always flowing through them. Magnetic fields can travel through most objects.

The electric and magnetic forces in EMFs are caused by electromagnetic radiation. There are two main categories of EMFs:

  • Higher-frequency EMFs are in the ionizing radiation part of the electromagnetic spectrum and can damage DNA or cells directly. Sources include sunlight and X-rays.
  • Low-to mid-frequency EMFs are in the non-ionizing radiation part of the electromagnetic spectrum and are not known to damage DNA or cells directly. Sources include electric power lines and appliances, radio waves, microwaves, cell phones, and wireless internet (WiFi).  Federal regulations are in place to help limit radiofrequency output from cell phones, and regulators may take action if emission levels are at levels that are hazardous to the user.

What if I am interested in reducing my exposure to EMF from cell phones or wireless devices?

There is no consistent evidence that exposure to EMF from cell phones and other wireless devices creates a human hazard. However, if you want to reduce exposure to non-ionizing EMF there are some steps you can take. These include:

  • Move farther away from a source. Exposure rapidly decreases as distance from the source increases. Using the speaker on your phone or using corded headphones when speaking on your cell phone and not keeping devices near you while sleeping will reduce EMF exposure.
  • Turn devices off. Devices like those that rely on Wi-Fi, such as cell phones, laptops, and WiFi routers, are sources of EMF even when not in use. Switching your cell phone to airplane mode also reduces exposure.
  • Limit Use. Reduce the number or length of calls, or amount of time spent on a device.

Where can I find information on EMF from cell phones or wireless devices?

A number of federal agencies have developed guidance and information on low-frequency, non-ionizing EMF. This guidance has found that most studies did not show any increased risk of health effects due to exposure to low frequency EMF, and that there is no established link between low frequency EMF and health risks.

The websites below can help explain what EMF is, describe current research, and give additional practical tips to reduce exposure for those who are interested:



Main number (617) 242-3035
RCP emergency number (617) 242-3453

Rings through to Massachusetts State Police


(617) 242-3457


Schrafft Center
529 Main St.
Suite 1M2A
Charlestown, MA 02129