The age-old saying that lightning never strikes the same spot twice is simply untrue. For example, the CN Tower in Toronto is struck by lightning an average of 75 times per year.
While lightning may seem rare, Canada receives an average of over 2.2 million flashes to ground each year, and a single bolt of lightning has enough power to peak at 100 million volts of electricity. That much electricity surging through a home or office at once can be catastrophic for electrical systems and permanently destroy your most expensive electronics.
What is Lightning Protection?
The origins of lightning protection systems in North America date back to one of the USA’s Founding Fathers, Benjamin Franklin. More than 200 years of lightning protection history have taught us that rods must be installed on the most vulnerable areas of a structure—e.g., the roof, chimney, tall metallic bodies, etc.—and must be provided with a low-resistance conductive path to ground.
Today, there are several types of code-compliant lightning protection systems in use, and they should always be installed by trusted and certified lightning protection companies, like Dobbyn Lightning Protection in Alberta. The different types include:
Integral systems
Mast-type systems
Overhead catenary wire systems
The Different Types of Lightning Protection
Lightning protection is available to anyone concerned about the damage caused by a lightning strike, including residential, commercial, institutional, and industrial structures. And the larger the structure—whether in footprint area, height, or both—the greater the chance of damage from lightning. In fact, using Environment Canada’s data for lightning in the Calgary to Edmonton region, a risk analysis shows that structures over 90 meters (300 feet) tall have a greater than one in ten chance of being struck by lightning each year.
Each type of protection has advantages:
Integral Systems: Integral systems utilizing standard lightning rods are the easiest to install and can be integrated unobtrusively into your building’s structure. Most rods are no more than 300 mm (1 foot) in height, and though they must be spaced at 6 m (20 ft) intervals at the perimeter of flat roofs, and along the ridges of peaked roofs, they present a minimal visual profile. The roof and ground conductors can also be concealed within the building envelope to further reduce the systems visibility. This type of lightning protection system can be installed on almost all types of structure, and is the only type installed on most residential buildings.
Mast Systems: Mast lightning protection systems can be made up of a single mast, or multiple masts spread over a wider area. An elevated lightning rod provides a zone of protection out to a certain distance away from the mast, such that any equipment or structure located within that zone is substantially protected from lightning strikes. Properly grounded flagpoles and radio towers can act as mast systems, as can fiberglass masts with dedicated lightning rods and conductors. Where these systems are used, a qualified lightning protection specialist or engineer must calculate the zone of protection and required separation distance between the mast and protected equipment.
Catenary Wires: Catenary wires, like mast systems, are effective for protecting wider areas where the majority of lightning current needs to be kept at a distance from the protected objects. Tank farms, munitions facilities, piers, and other exposed areas are good candidates for catenary lightning protection. Due to their high visibility, this type of system is geared more towards industrial and military applications. Again, a qualified specialist must provide an analysis and design for catenary systems.
Which Lightning Protection System is Right for You?Deciding which type of lightning protection is best for you depends on your structure, vulnerabilities, and your aesthetic requirements. Moreover, you need a professional to assess your property, and to design lightning protection around the structure’s most susceptible strike points. Dobbyn Lightning Protection has over 50 years’ experience combined in lightning protection and outdoor lighting in Calgary. Our team will assess your property and design a system that meets the most current lightning protection standards. Schedule your appointment now at 403-278-4441 or request information about our lightning protection systems online.