We lost Jasmine Flankey
on July 4, 2009. When I say “we,” I
mean Montana collectively. More
specifically, I mean electricians and inspectors in Montana. When I say “lost her,” I mean she is
dead. More accurately, she was killed.
Jasmine died as a result
of electric shock. She perished when she
touched the metallic ductwork of a roof-mounted HVAC unit. The ductwork had become energized by a faulted
lighting circuit inside the building below.
In an effectively grounded electrical system, the ground-fault
energizing the ductwork would have caused a breaker to trip and cleared the
fault, rendering the circuit harmless.
The whole story is a bit
complicated and technical. Put simply,
had six inches of wire been used to “jumper” between that electrically
isolated section of duct and the rest of the grounded electrical system,
Jasmine Flankey would not have received life-ending electric shock. As it was, the duct remained energized,
deadly. When Jasmine—while in contact
with that duct—touched a properly grounded metallic piece of equipment, electric
current surged through her body. She had
been on the roof of a church in Missoula, Montana to watch fireworks. Jasmine was eight at the time of her death.
At one time, I actually
objected when an electrical inspector in Helena wanted me to install the same kind of six-inch jumper wire at several sections of ductwork on a job under
inspection. I thought he was
overreaching. What good was a six-inch
bonding jumper on non-electrical ductwork?
I was ignorant.
Today, that girl and I
are driving to the headquarters of Yellowstone Park in Mammoth Hot Springs. Tomorrow, I am teaching a grounding and
bonding class to a dozen park employees there.
It’s a big deal. Grounding and bonding is a big deal. It’s a dense subject.
The class will begin with
a telling of the Jasmine Flankey story.
As a class, we break down the grounding system that killed her. Then, we
spend eight hours discussing the hundreds of other details associated with grounding
and bonding—one hour for each of Jasmine Flankey’s years.
--Mitchell
Hegman
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