Electric and magnetic fields are invisible lines of force surrounding any wire or device that uses electricity. They are created whenever electricity flows through a wire (eg. overhead power lines, electric appliances, or electrical cords or wiring) because these fields are found wherever there is electricity.
ENMAX understands some individuals may have concerns regarding electric and magnetic fields (EMF). Scientific evidence to date has not established adverse health effects resulting from exposure to power-frequency EMF at levels normally encountered in homes, schools and offices. However, we continue to monitor the issue through our work with the Canadian Electrical Association's (CEA) EMF task group, and recognize no single study will resolve this issue. We commit to staying informed about EMF and offering information and in-home measurements to our customers so they can make their own informed decisions regarding this issue.
Electric fields are produced by voltage, which can best be compared to the pressure of water in a pipe. They are measured in kilovolts per meter (kV/m). There are electric fields whenever voltage is present. Electric fields are present whenever an appliance is plugged in, even if it is turned off. The higher the voltage, the higher the electric fields.
Magnetic fields are produced by electrical current, which is comparable to the quantity of water flowing through a pipe, and are measured in microtesla (uT) or milligauss (mG). They are only present when power is flowing through a wire – so when an appliance is turned on. The more current flowing through a wire, the higher the magnetic field. While electric fields are easily shielded or weakened by conducting objects (ie; trees, buildings, and human skin), magnetic fields are not. However, both electric and magnetic fields weaken with increasing distance from the source.
Yes, the earth produces EMFs, mainly in the form of DC (also called static fields). Electric fields are produced by thunderstorm activity in the atmosphere and magnetic fields are thought to be produced by electric currents flowing deep in the earth's molten core.
Generally, the strongest EMFs around the outside of a substation come from the power lines entering and leaving the station. The strength of the EMFs from transformers decreases rapidly with increasing distance. Beyond the substation fence, the EMFs produced by the equipment within the station are typically indistinguishable from background levels that naturally occur in the earth.
For further information, please call ENMAX at 403-514-3724,
email us or visit these websites:
Customers are free to purchase natural gas services or electricity services from a retailer of their choice. For a list of retailers, visit ucahelps.alberta.ca or call 310-4822 (toll free in Alberta).