Protecting your home from lightning damage

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RBC I Colorado experiences the second highest incidence of lightning strikes in the nation, second only to Florida, and direct or nearby strikes may cause devastating damage to buildings, start fires and even cause severe injury or death.
Moreover, lightning strikes may cause serious damage to expensive electronics systems and wiring. Similarly, over voltages or spikes created in power transmission lines and transformers, circuit protectors and weather-related damage to power lines and delivery systems may all result in power surges entering home electrical wiring systems, causing often undetected damage which shortens the life of electronic devices.
With the proliferation of sensitive electronic and electrical devices that are now widely used in homes and businesses, it is very important to provide whole house surge protection devices installed on electrical power distribution system equipment as well as telephone lines, satellite and cable TV coaxial cable running from antennas or distribution lines to receivers, heating and cooling system controls and much more, to protect these costly investments from over voltage surges. Now, even lighting devices such as standard and compact fluorescents and the new light-emitting diode (LED) lamps all use electronic ballasts and power supplies which are very sensitive to surges and can be expensive to replace. A direct-hit lightning strike may be so powerful that all the protective devices are destroyed, as lightning bolts produce hundreds of thousands of volts and amps and the bolt is five times hotter than the surface of the sun. However the damage may typically be considerably reduced and fires may be prevented if multi-stage surge protector devices are installed, to help lessen damage to buildings, wiring and electronic devices. Having multiple or redundant layers of fail-safe surge protection devices in place may be the best insurance to prevent catastrophic damage from over voltage surges.
Lightning strikes are only a part of the problem. Electrical equipment used in the home can generate surges and over voltage incidents whenever they turn on and off. Devices causing these events might include refrigerators and freezers, air conditioners, pumps, motors and even lighting instruments. While the surges created by these devices are generally not nearly as catastrophic or damaging as a single lightning strike, over time they can gradually cause damage to sensitive electronic devices and circuits used in computers, home theatre installations and much more, and thus shorten the expected life of the devices by causing premature failure or malfunction.
The Institute of Electrical and Electronics Engineers (IEEE) has authored a document entitled “How to Protect Your House and its Contents from Lightning” available online which compiles the recommended best practices and standards for lightning and surge protection of residences from such organizations as the National Electrical Code (NEC) of the National Fire Protection Association (NFPA), the National Electrical Manufacturers Association (NEMA) and Underwriters Laboratories (UL).
Here are some recommended actions to assist you in protecting your home and electronics devices:
n Seek expert advice and services from licensed, experienced electricians and local electric utility providers. These organizations are familiar with surge protection methodology and standards to evaluate your home wiring and make recommendations on appropriate grounding and whole house surge protection devices best suited to the wiring and technology used in your home.
n The first line of defense: electrical utility meter surge protectors, which can be provided by local electrical utility providers which offer reasonably priced devices that fit behind the power meter on the outside service entrance panel of your home to serve as a first line of defense against lightning strikes and over voltage surges entering the home from external power lines. These devices are designed to conduct such surges to ground so they are less likely to enter the home wiring systems and thus may help to prevent high voltage electrical flash overs that may start fires and severely damage wiring.
n The second line of defense: breaker switch panel whole house surge protectors. A high capacity whole house surge protector should be installed in the breaker switch panel box (that distributes power to all the circuits in your home). This device will also conduct surges to ground that may get past the primary surge protector at the meter and will also help neutralize surges generated within the home from operation of other electrical devices.
n The third line of defense: device-specific surge protectors and uninterruptible power supplies. All sensitive electronic devices should be equipped with the more commonly known surge protection multiple outlet device that directly provides power from the wall outlet to home theatre systems, televisions, computers, microwaves and other electronics. These devices also can provide protection for surges that may enter the home via phone lines, or from cable and satellite TV coaxial cables and absorb surges before they can enter electronic devices, or the low voltage inputs from receivers and outside antennas, telephone lines, etc. Always purchase a high quality UL certified surge protector with a high energy absorbing rating. High quality fast-acting units are more expensive but often carry equipment replacement warranties that will insure for any damage to your electronic devices that are connected to the surge protector and often have very high funding limits to cover full replacement or repair of your damaged equipment.
n Uninterruptible power supplies (UPS), are often used with computer and offer not only surge protection and telephone line and satellite/cable TV signal protection, but provide battery backup power to the device during power outages. The UPS can help save computer data files from being lost due to a sudden power outage or keep other devices running while the main power is off.
n Ground fault and arc fault circuit interrupters (GFCI/AFCI) are devices that detect abnormal voltage differentials resulting from inappropriate flow of electricity which may be caused by a faulty or wet extension cord or appliance, contact by a person with an energized circuit, or an arc between wiring conductors due to faulty insulation. The electronic circuits contained in these devices will instantly switch power off, may help prevent electrical shock and resulting injury or death and may also help prevent electrically caused fires. New wiring codes require these devices in affected areas for safety and fire prevention and should be considered even for upgrading wiring in older homes as a safety measure. They may also assist in prevention or reduction of damage to electronic devices. Consult with a licensed electrician for application and installation.
See the NOAA/NWS website for advice on lightning safety at