Lightning Alley is not just a catchy name for a street or the local bowling lanes. It's the name dubbed to a notorious region in central Florida that is in the heart of the most lightning-prone area in the entire country. And that lightning strike may come at the most inopportune time.
Not only can this force of nature cause bodily injury and severe damage to property, it also has the power to disrupt or destroy a police department's 9-1-1 communications system, which is intended to assist residents during an emergency. That's exactly what happened in the middle of one Florida storm.
When a Walmart in the city of Bushnell was relocated, the facility was donated to the county for their use. The Sumter County Sheriff's Department decided to open its new offices in this building, including housing its emergency communications there.
One serious problem was that the electrical system was built for a 1970's vintage department store, not a critical communications and public safety facility. During one lightning storm in particular, the 9-1-1 system failed, leaving county residents without police, fire or ambulance response.
Inspection of the existing electrical system showed that it was badly flawed, mainly due to improper connectors and poor bonding and grounding. The communications tower, for example, had its own independent and inadequate grounding. The emergency generators and building structure were all independently grounded, each with its own ground rod, exposing its poor design. The main grounding electrode consisted of a single galvanized steel rod from the 1970s, with very high resistance to earth.
A new system was designed and installed for under $40,000, a minimal cost considering the value of the equipment protected, and improved public safety it brought to the residents of Sumter County.
"To be effective, the entire grounding system needs to be properly designed, using listed connectors and corrosion resistant materials," said Dave Brender, National Program Manager for the Copper Development Association, CDA. "Lightning protection systems in particular must be well-grounded to work properly, and could make matters worse if they are not. Copper and its alloys are the most common materials in use for this application because they provide superior corrosion resistance and avoid oxidation problems at connections.
Copper is also easy to install and durable," Brender added.
Central Florida is not the only region in the U.S. affected by severe weather. Similar 9-1-1 and broadcast facilities are employed in areas all over the country where communications is critical and the chances for lightning strikes are quite high. Having proper copper-based grounding and bonding should be a top priority where an entire system can get crippled by lightning.
Related Stories
| Aug 11, 2010
Nurturing the Community
The best seat in the house at the new Seahawks Stadium in Seattle isn't on the 50-yard line. It's in the southeast corner, at the very top of the upper bowl. "From there you have a corner-to-corner view of the field and an inspiring grasp of the surrounding city," says Kelly Kerns, project leader with architect/engineer Ellerbe Becket, Kansas City, Mo.
| Aug 11, 2010
BIM adoption tops 80% among the nation's largest AEC firms, according to BD+C's Giants 300 survey
The nation's largest architecture, engineering, and construction companies are on the BIM bandwagon in a big way, according to Building Design+Construction's premier Top 50 BIM Adopters ranking, published as part of the 2009 Giants 300 survey. Of the 320 AEC firms that participated in Giants survey, 83% report having at least one BIM seat license in house, half have more than 30 seats, and near...
| Aug 11, 2010
Integrated Project Delivery builds a brave, new BIM world
Three-dimensional information, such as that provided by building information modeling, allows all members of the Building Team to visualize the many components of a project and how they work together. BIM and other 3D tools convey the idea and intent of the designer to the entire Building Team and lay the groundwork for integrated project delivery.
| Aug 11, 2010
Great Solutions: Healthcare
11. Operating Room-Integrated MRI will Help Neurosurgeons Get it Right the First Time A major limitation of traditional brain cancer surgery is the lack of scanning capability in the operating room. Neurosurgeons do their best to visually identify and remove the cancerous tissue, but only an MRI scan will confirm if the operation was a complete success or not.
| Aug 11, 2010
Great Solutions: Collaboration
9. HOK Takes Videoconferencing to A New Level with its Advanced Collaboration Rooms To help foster collaboration among its 2,212 employees while cutting travel time, expenses, and carbon emissions traveling between its 24 office locations, HOK is fitting out its major offices with prototype videoconferencing rooms that are like no other in the U.
| Aug 11, 2010
2009 Judging Panel
A Matthew H. Johnson, PE Associate Principal Simpson Gumpertz & HegerWaltham, Mass. B K. Nam Shiu, SE, PEVP Walker Restoration Consultants Elgin, Ill. C David P. Callan, PE, CEM, LEED APSVPEnvironmental Systems DesignChicago D Ken Osmun, PA, DBIA, LEED AP Group President, ConstructionWight & Company Darien, Ill.
| Aug 11, 2010
Inspiring Offices: Office Design That Drives Creativity
Office design has always been linked to productivity—how many workers can be reasonably squeezed into a given space—but why isn’t it more frequently linked to creativity? “In general, I don’t think enough people link the design of space to business outcome,” says Janice Linster, partner with the Minneapolis design firm Studio Hive.