Section 4: Safety Guidelines and Warranty Information98 4A: SafetyConsumer Information on Wireless Phones(The following information comes from a consumer informationWeb site jointly sponsored by the U.S. Food and Drug Administration(FDA) and the Federal Communications Commission (FCC), entitled“Cell Phone Facts: Consumer Information on Wireless Phones.” Theinformation reproduced herein is dated April 3, 2002. For furtherupdates, please visit the Web site: http://www.fda.gov/cellphones/.)1. What is radio frequency energyRadio frequency (RF) energy is another name for radio waves. It is oneform of electromagnetic energy that makes up the electromagneticspectrum. Some of the other forms of energy in the electromagneticspectrum are gamma rays, x-rays and light. Electromagnetic energy (orelectromagnetic radiation) consists of waves of electric and magneticenergy moving together (radiating) through space. The area where thesewaves are found is called an electromagnetic field.Radio waves are created due to the movement of electrical charges inantennas. As they are created, these waves radiate away from theantenna. All electromagnetic waves travel at the speed of light. The majordifferences between the different types of waves are the distances coveredby one cycle of the wave and the number of waves that pass a certainpoint during a set time period. The wavelength is the distance covered byone cycle of a wave. The frequency is the number of waves passing agiven point in one second. For any electromagnetic wave, the wavelengthmultiplied by the frequency equals the speed of light. The frequency of anRF signal is usually expressed in units called hertz (Hz). One Hz equalsone wave per second. One kilohertz (kHz) equals one thousand waves persecond, one megahertz (MHz) equals one million waves per second, andone gigahertz (GHz) equals one billion waves per second.RF energy includes waves with frequencies ranging from about 3000waves per second (3 kHz) to 300 billion waves per second (300 GHz).Microwaves are a subset of radio waves that have frequencies rangingfrom around 300 million waves per second (300 MHz) to three billionwaves per second (3 GHz).