At 3:00 a.m., the owner of a plumbing supply store was awakened by the insistent ringing of his bedside phone. He became fully awake when the caller reported that his store was on fire. The store was almost fully engulfed by the time firefighters arrived.
A dispute arose between the store's insurance carrier and the owner over the cause of the fire. The owner's attorney retained me to help determine the cause of the blaze. Although a longtime client, I reminded him that I was not a fire expert per se. He explained that since an engine-powered forklift was found near the epicenter of the fire, I might be able to help.
At the store's remains, I met with the attorney and the usual cast of characters, including other attorneys and consulting engineers, city firemen, and fire inspectors. It was unusual, however, to see uniformed policemen and police arson squad members. When I asked about the reason for the arson squad, I was told that the area was a hotbed of gang activity and the store owner was once threatened by a gang member. Analysis of the fire and entry alarm logs showed, however, that there was no forced entry until the arrival of the firefighters.
The fire detectors showed a spread of heat from the approximate location of the forklift outward. The fire experts' consensus was that flames from the forklift spread to stacks of cardboard boxes of newly received plumbing fixtures. The flames spread quickly in the crowded storage area before any sprinkler was deployed, but no traces of an accelerant were found. The firefighters found an electric pipe threading machine in the debris. An engineer from the pipe threader's company was summoned and later that day proceeded to disassemble the threader. It appeared that damage to the pipe threader was external and no burned or arced internal wires were found.
The burn patterns on and near the forklift indicated that the fire started in or near the engine bay. The molded, glass fiber-reinforced engine cover, driver's seat, steering wheel, and plastic molded instrument panel were almost totally burned away. The solid rubber tires on the driver's right side of the forklift were charred and melted. Although I pondered whether the fire spread from the stacked appliance boxes to the forklift, I continued with my inspection of the forklift.
To permit site cleanup and demolition, the forklift was moved to a rented garage facility near the fire site where the forklift inspection could proceed safely.
The owner and his forklift operator said that the truck was generally reliable, but that the hydraulic control linkages needed more than routine maintenance and adjustment. They also complained that the clamshell-style engine cover seemed flimsy and sagged to such a degree that drivers would sit on an extra cushion.
I noticed that the cable from the battery's positive terminal to the starter solenoid ran across the top of the stamped steel engine valve cover. The insulation was melted from the cable, but a close look revealed arced conductors. Hmmm. Did the sagging cover press on the cable? And was the battery cable properly installed? I came armed with maintenance and repair manuals that clearly showed using clamps and ties to locate the cable ahead and below the surface of the valve cover.
The forklift was purchased used from a repair shop that also did maintenance and repair work. That shop had made repairs, including replacing the battery cable in question. My attorney/client retained a metallurgist to examine the exterior and interior surfaces of the valve cover. His microscopic examination revealed severe discoloration on both surfaces and confirmed the presence of temperatures high enough to ignite accumulations of residual fluids. I now had a grasp of the cause of the fire.
My opinion report cited the sagging engine compartment cover that overnight pressed on an improperly installed cable, resulting in high temperature arcing that ignited residual flammable fluids and dirt. The insurance company agreed that the loss was not due to the business owner's wrongful action or inaction and agreed to settle the claim.
This entry was submitted by Myron J. Boyajian and edited by Rob Spiegel.
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