Electromagnetic radiation (EMR) is a type of radiation that consists of waves of the electromagnetic field, which propagate through space and carry momentum and electromagnetic radiant energy. Electric and magnetic fields together are referred to as electromagnetic fields (EMFs), and they are caused by electromagnetic radiation. EMFs are typically grouped into one of two categories by their frequency:

• Non-ionizing radiation: This is low-level radiation that is generally perceived as harmless to humans. It includes low- to mid-frequency EMFs, such as static fields, magnetic fields from electric power lines and appliances, radio waves, microwaves, infrared radiation, and visible light.

• Ionizing radiation: This is high-level radiation that has the potential for cellular and DNA damage. It includes higher-frequency EMFs, such as x-rays and gamma rays.

EMFs are associated with the use of electrical power and various forms of natural and man-made lighting. Common sources of non-ionizing EMFs include household appliances like microwave ovens, cellphones, hair dryers, and washing machines, as well as power lines and MRIs. Radiofrequency radiation is emitted from wireless devices like cell phones, smart meters, tablets, and laptop computers, as well as radio and television signals, radar, satellite stations, and MRI machines.

The effects of EMR upon chemical compounds and biological organisms depend both upon the radiations power and its frequency. EMR of visible or lower frequencies (i.e., visible light, infrared, microwaves, and radio waves) is called non-ionizing radiation, because its photons do not individually have enough energy to ionize atoms or molecules, or break chemical bonds. No mechanism by which ELF-EMFs or radiofrequency radiation could cause cancer has been identified. Despite extensive research, to date there is no evidence to conclude that exposure to low-level electromagnetic fields is harmful to human health.