Malcolm, John D. Opposing Views. Fire and Arson Investigator. Volume
42 Number 4. June 1992.
Abstract: In this article, the author addressed issues raised
in the December 1991 issue of Fire and Arson Investigator, written by Thomas
Shefchick. The author of this article disagrees with his colleague Shefchick
on some instances that Shefchick dismisses as fire causes. The author, John
Malcolm, thinks that the over-sized lamping, dirt and debris near electrical
equipment, and electrical arcs could all be causes of fires.
Shefchick stated that over-lamping of light fixtures does not cause fires.
Malcolm disagrees, citing his twenty-five years in the electrical consulting
field as evidence. He claimed that oversized lamped light fixtures could
start fires if suitable conditions for combustion exist. One example of
a light fixture known to start a fire is the recessed incandescent light
with over-sized lamping. When this type of light is located adjacent to
a wooden ceiling or another combustible material, it has the potential to
become an ignition source.
Another point Shefchick raised concerned dirt and debris in electrical
equipment. He stated that there is always debris surrounding electrical
equipment. Malcolm disagreed referring to the NFPA standards on the subject,
which say that electrical equipment should not be stored near combustible
Malcolm also disagrees with Shefchick about electrical arcs. Shefchick
states that short circuits cause fires, not arcs. Malcolm offers an example
in which an arc does ignite a fire. The meltdown of a 480-volt switch gear
with phase to phase faults does cause arcing which could eventually cause
For more information, contact:
International Association of Arson Investigators (IAAI)
300 Broadway Suite 100
St. Louis, MO 63102-2808