Center for Safer Wireless
Promoting Safety in Our Wireless World

Forms of Radiation
Radiation is energy in motion radiating away from its source. This form of energy is expressed as wavelengths along the electromagnetic spectrum.  With visible light dividing them, radiation is broken down into ionizing and nonionizing radiation.
Ionizing vs. Nonionizing Radiation
Ionizing radiation has short wavelengths that have enough power to knock neutrons off their nuclear orbits and can cause permanent damage on the cellular level such as genetic mutations and cancer. 
Nonionizing radiation has longer wavelengths with generally less power. Wireless technology operates by using radiofrequency radiation which is nonionizing radiation. Radiofrequency radiation, also known as microwave radiation, uses nonthermal levels of radiation, which do not heat living tissue.  Common wireless products run on radiofrequency radiation.
Thermal levels of radiation heat living tissue and cause harmful biological effects. Wireless safety standards are based on the technology using nonthermal levels, thought to be safe because it doesn't heat tissue.
Some scientists point to research indicating biological changes in DNA, leakage in the blood brain barrier, and other reported health effects from exposure to radiofrequency radiation.  These scientists are calling for biologically-based safety standards for wireless technology. 

This graph depicts the electromagnetic spectrum with both  frequencies and wavelengths associated with products and technology.

Wireless Products Operate at the Microwave Level
Cell phones, cordless phones, smart meters, pagers, radar, Wi-Fi, baby monitors, and satellite communications function by using different radiofrequencies at the microwave level.  A microwave oven may come to your mind when you read the term microwave.  Microwaves used in wireless signaling are different from microwave ovens due to frequency, power, and heat.  Cell phones operate at 750 to 950 MHz (mega hertz) while microwave ovens function at 2450 MHz.  Microwave ovens obviously generate heat while wireless products don't.  Basically, microwave ovens use high frequency and high power, and cell phones use high frequency and low power. 
How is a Radio Wave Different from a Microwave?
Radio waves are low levels of transmission power enabling signals to and from your cell phone.  These non-ionizing frequencies in the few hundered MHz range are safe.  But when the signal strength grows to 800 MHz and higher, these waves become microwaves. The older cordless house and office phones were a few hundred MHz of radio waves, but the more you moved from the base, the weaker the signal. You would soon lose the call, or it would break up.  Today cordless phones are 900 MHz and higher so that you don't lose calls when moving from room to room, and you can even go outside. These phone operate in the microwaves/infrared waves of radiating power.