Characteristics of an EMF

Electromagnetic fields known as EMF's are everywhere in space and on the earth. Some are natural in nature while others are man-made. EMF's can cancel out other EMF's that they come in contact with, or they can combine into one. Although at times it seems EMF's are unpredictable, there are several characteristics that define every action in every electromagnetic field.

Electric Fields

• Electric fields exist anywhere there is an electric charge, be it man-made or in nature. All matter has a positive and negative charge that react with each other. An electrical field is created in the space between those positive and negative charges. The strength of the field is proportional to the amount of voltage in the electrical system. The fields strength decreases as the distance from the source increases.

Magnetic Fields

• A magnetic field is created when electrical current flows. It's an invisible force existing in the space around the source of the current. It's field strength is directly proportional to the amount of electrical current, or more simply stated as the speed the electrical charge is traveling. Power lines are the most common types of magnetic fields because of the continual flow of electricity.

Wavelength and Frequency

• Electromagnetic fields expand in waves in the same way waves react in water. The distance from the top of one wave to the next is one wavelength. Frequency is how many waves cross one point each second. Longer wavelengths produce lower frequencies. The strength of the wavelength and frequency defines the strength of the electromagnetic field. Frequency will vary depending on the speed and amount of power consumed, while wavelength remains constant.

Ionizing and Non-ionizing

• Electromagnetic waves are carried by particles know as quanta. High frequency quanta's carry more energy, and some carry so much energy they are able to break bonds between molecules. Gamma, cosmic and X-rays are high energy quanta that are called ionizing radiation fields. Fields that are too weak to break molecular bonds are called non-ionizing radiation. Man-made EMF's such as microwaves and radio frequency fields are non-ionizing.