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TECHTRENDS
According to OSHA, an arc flash is a phenomenon where a flashover of electric current leaves its intended
path and travels through the air from one
conductor to another, or to ground. The
results are often violent and when a human
is in close proximity to the arc flash,
serious injury and even death can occur.
Arc flash can be caused by many things
including:
• Dust
• Dropping tools
• Accidental touching
• Condensation
• Material failure
• Corrosion
• Faulty installation
With so many causes, it’s no surprise
that arc flash incidents can vary in conse-
quence and severity. But one thing’s for
sure: the results can be catastrophic for an
individual. According to IEEE (Institute
of Electrical and Electronics Engineers),
though electrical incidents represent a rela-
tively small percentage of all work-related
incidents, they are disproportionately fatal
and, in the case of burns, they may result
in extended hospitalization and rehabilita-
tion. “The most frequently identified con-
sequences associated with an arcing fault
injury are thermal burns, shrapnel injuries,
and hearing and sight impairments. In addi-
tion, electrical arcs often cause workers to
fall, resulting in disabling injuries or death.
In such cases, the cause of injury or death
may be recorded as a fall, and not electri-
cal, further distorting the real hazard,” says
the organization.
An Ounce of Prevention
According to Piero Fagiolo, product
manager for industri-
al products at Rittal
Corporation, the explo-
sive release of energy
that occurs when there
is an arc fault may be
the result of equipment
failures due to corro-
sion, insufficient insu-
lation, conductive dust,
or contact by animals.
Rittal’s expertise is in
developing products like
enclosures and accessories for data collection
in industrial environments, and fully knows
the critical role NFPA
(National Fire Protection
Association) compliance can play in system
design — as well as the
ability to isolate power
within respective enclosures.
But equipment design can only go so far
and, unfortunately, human error is more
prevalent than equipment failure as the
cause of arc flash incidents, says Fagiolo.
Often, phase-to-phase and phase-to-ground
contact can occur due to distractions
when an operator is working on energized
equipment. “Another common contributor
to an arc flash incident is a failure to use
insulated tools,” he says. “And there is
always a chance of dropping conductive
components, such as screws or small tools,
onto live circuits.” Even the accumulation
of dust and metallic debris can lead to an
incident, and it’s critical to keep tools and
work components organized, as well as
reduce any potential distractions.
It’s also important to note that, while
the vast majority of accidents involve
high voltage applications (480 VAC and
above), arc flash can occur at lower voltages. Fagiolo stresses that control panels,
disconnects, bus switches, motor controls,
motor starters, and switchgear are common
locations for arc flash, and that its prevention “should be considered from the very
beginning of any application design.”
Better Protection –
All The Way
There are many things that facility managers can do to reduce or mitigate the arc
flash hazards associated with electrical
incidents and improve the safety of their
workers, say Brett Felton, national market manager for the electrical distributor
Arc flash incidents are rare, but
disproportionately fatal – meaning manufacturers need regular
reminders of the do's and don’ts
of electrical repair.
IN A FLASH
