Frequently Asked Questions on Electrical Effects

Q. Will my radio or television reception be affected by a transmission line?

A. TV reception problems are unlikely. If they happen, they can be solved by either changing the antenna or relocating it. We can’t do anything about poor reception you may have had before a line was built, but if you think you may be experiencing poor television reception as a result of a transmission line, please give us a call. AM and CB radio reception can be affected, particularly when directly under any power line, and the amount of interference depends on the type of radio and antenna. AltaLink conducts measurements to ensure it complies with interference guidelines.

Q. Will my cable or satellite television or wireless internet system be affected by a transmission line?

A. A transmission line should not cause reception problems for cable or satellite television or wireless internet systems. If your cable or satellite provider suggests that a transmission line is affecting service, AltaLink will investigate.

Q. Will my GPS (Global Positioning System) receiver be affected by a transmission line?

A. Reception problems for mobile GPS receivers are unlikely. AltaLink staff use GPS receivers near our existing transmission facilities and do not experience problems. Please contact us if you believe our power line is causing a problem with your GPS device.

Q. Will my cardiac pacemaker be affected by the transmission line?

A. A number of sources of EMF have been reported to affect some cardiac pacemakers. Potential sources of interference can include cellular phones, CB radios, wireless computer links, microwave ovens, microwave signals, radio and TV transmitters, paging transmitters, welding equipment, generating plants, rail transportation and power lines.

Transmission line magnetic fields are generally too weak to affect such devices. Very high electric fields can interfere with some models of pacemakers, but trees, buildings, fences and vehicles provide effective shielding from the electric field. If you have a concern, AltaLink will assist you in getting the information to help you determine if your device is immune to electrical interference from this and other sources. Most of these devices are designed to filter out electrical interference or revert to a safe mode of steady pacing if interference becomes too great.

Q. How are nearby metal buildings and wire fences affected by transmission lines?

A. Electrical charges will not normally accumulate on buildings close to transmission lines because appropriate grounding already exists. AltaLink will help ensure that metal buildings are properly grounded to avoid the build-up of an electrical charge.

When AltaLink is constructing a new transmission line near a building or fence, we will ground them so that they do not pose a shock problem. Upon request, we can also check or ground other nearby fences and other structures. Let us know if you are planning to put up a new building, fence or gate near an existing line, and we’ll advise you on how to ground them and ensure they won’t affect access to the right-of-way.

Q. Will a transmission line generate noise?

A. Sometimes a hum, popping, crackling or hissing sound can be heard coming from high-voltage lines. This noise is usually most noticeable in rainy or foggy conditions. AltaLink ensures our transmission lines comply with the noise guidelines set out by the Alberta Utilities Commission.

Q. Is there a difference between alternating current (AC) and direct current (DC) lines?

A. An AC line operates at the power line frequency of 60 Hertz, meaning the direction of the current alternates 60 times per second. The current in a DC line continually flows in the same direction, similar to the current in a flashlight or a car battery.

There are many factors to be considered when comparing AC and DC transmission lines. Both types of facilities produce EMF and other effects such as audible noise, induction, and small amounts of radio and TV interference.