Lightning strikes start church fire

NFPA Journal, May/Jun 2002 by Tremblay, Kenneth J

firewatch

FLORIDA

A church sustained $1.3 million in structural damage after lightning struck the building in two places, igniting it and causing a power surge through the electrical wiring. These events led to numerous points of ignition in the attic and a second ignition at a comer of the second-floor day school area.

The 51-year-old, two-story church had concrete-and-- block walls, wood roof trusses, and a slate roof, It was 122 feet (37 meters) long and 80 feet (24 meters) wide, and contained a workshop and a day care center. Only the day care center had a fire detection system, which operated after firefighters began suppression activities. There were no sprinklers.

Nearby lightning strikes caused a massive power surge in the building's electrical system and first-floor main power room, causing all the wiring and fuses in one of three main circuit breaker boxes to melt. The surge continued through the buildings internal wiring and arced at several points in the electrical distribution system. A second, more direct, lightning bolt struck a second-- floor corner of the building, causing the roof overhang to smolder. The current also spread through and out of the conduit, igniting several areas of wood truss in the attic.

A passerby called 911 at 1:12 a.m. The building, valued at $3 million, sustained an estimated $1.3 million in damage. Contents, valued at $500,000, sustained an estimated $250,000 in losses.

A National Weather Service Doppler radar map showed 500 lightning strikes within one-half mile (0.8 kilometers) of the church during the storm.