Abstract
Forest fires are generally consciously or unconsciously the work of man for various reasons. Fires generated byvoltaic arc between power lines and the underlying trees do not occur often. These few cases may be only demonstratedby analyzing around the site where the arc may have been generated. Material such as leaves, bark and soil can beanalyzed to find the metallic residues from the fused cables. The electrical cables usually composed of aluminum orcopper alloys, when involved in an electric arc may spray fused micro-drops of metals, increasing the natural levelof such elements. In two cases, the Al and Cu concentrations were increased by between 2.56 to 13.9 times thebackground levels. Electron microscopy of leaf surfaces has identified some profound alterations produced by theintense heat of the electrical discharge.
Abstract
In 2009-2013, U.S. fire departments responded to an estimated average of 56,000 structure fires per year in homes that involved heating equipment. These fires resulted in annual losses of 470 civilian deaths, 1,490 civilian injuries, and $1.0 billion in direct property damage. These homes included one- and two-family homes (including manufactured homes) and apartments (including townhouses and other multi-family dwellings).Space heaters are the type of equipment most often involved in home heating equipment fires, figuring in two of every five fires (40%). The fires involving space heaters accounted for 84% of the civilian deaths and 75% of civilian injuries in home fires caused by heating equipment, as well as over half (52%) of direct property damage. Another one-third (32%) of fires involved a fireplace or chimney, but these fires accounted for a much smaller share of civilian fatalities (5%) and civilian injuries (6%). Central heat and water heaters were responsible for 12% and 10% of home fires caused by heating equipment, respectively.
By Charles C. Roberts, Jr., Ph. D., P.E.
Automobile engine coolant related fires may result from engine coolant leakage,an increase in the concentration of the glycol in the water/glycol mixture, thenature of the vapor/particle distribution, and contact with an ignition source inthe engine compartment. Ethylene glycol, a common coolant, is a flammableliquid with an ignition temperature near 800F. In recent years, propylene glycolis being used because of environmental reasons. Propylene glycol is also aflammable liquid with an ignition temperature near 700F. In an automotiveapplication, the glycol is mixed with water at about a 50/50 ratio. Ignition of thisconcentration of coolant is difficult because of the water. When released at hightemperatures into the atmosphere where the water evaporates, the glycolvapor/liquid droplets can reach the state of an ignitable mixture. Typical ignitionsources in the engine compartment include hot surfaces (exhaust manifold,exhaust system) and electrical components (relays, distributor, spark plug wires).Automobile accidents, resulting in hot vapor expulsion from the coolant system,are also known to cause fires.
Abstract
In this paper, we review the research results about the identification of the electrical fire trace evidence and the fire reason recognition. We point out the existing problems and put forward the corresponding suggestions to promote the development of the cause of the fire investigation and make it better to serve for the work of fire investigation.
From Out of the Abyss...
This week’s article from the past is titled Incendiary Fires Can Be Spotted and was written by Benjamin Horton, CPCU, who was President of the National Adjuster Traing School in Louisville, Kentucky.. It is taken from the Decembe 1968 Vol. XVI No.5 issue.
In the new issue of NFPA Journal®, President Jim Shannon said the Association will focus on the leading causes of home fires, including cooking. "We also need to continue to push hard for home fire sprinklers. That's still a large priority for NFPA, and we plan to work very aggressively in 2014 on our residential sprinkler initiative," he said.
