Is it safe to use temporary wiring?
Yes, as long as the
wiring is the correct size and the installation meets the
requirements of the National Electrical Code (NEC). Most people use
temporary wiring at one time or another as with Christmas lights, or
party lights in the yard. Extension cords are an application of
temporary wiring. But temporary wiring is for a temporary purpose
and must be removed immediately after use.
Why is it a hazard to step on a wire?
Besides the tripping hazard, you may
damage the internals of the wire, e.g., break strands of conductors,
which could cause overheating and a fire, or damage the insulation
causing an electrical shock hazard.
What do I do if I have to run a wire
across the floor?
We all have wires on
the floor of our offices, but you should have the wire protected
from being stepped on and also the tripping hazard by running the
wire along the baseboard or under desks. In laboratories and work
areas, if you have to run the wire where it is subject to damage,
you should protect it with commercial wire covers.
What are the acceptable applications
for a power strip?
Power strips, 6
outlet power taps, or temporary power taps are listed by UL under
standard UL1363 titled, ďRelocatable Power TapsĒ (RPTís). They are
designed for high concentration of low ampere loads. RPTís are
described by UL as a relocatable multiple outlet extension of the
branch circuit to supply laboratory equipment, home workshops, and
to provide outlet receptacles for computers, audio and video
equipment and other low power equipment. They are not to be used as
extension cords, connected to extension cords, daisy chained
together, for high power demand equipment, or used outdoors or in
How far can I run my extension cord?
The distance for
running an extension cord is dependent on the power requirements of
the utilization equipment and the wire size of the extension cord.
For light loads, say a radio or lamp with 60 watt bulb you could
easily use a light duty extension cord for 12 feet, however, for an
air conditioner you might only be able to use a heavy duty extension
cord of 8 foot. The length of the extension cord depends on the
application, for example some outdoor electric hedge trimmers and
weed whackers allow 100 foot of 12 gauge wire.
Can I plug one extension cord into
No, extension cords
are rated by the manufacturer for the load being attached at the
end of the cord. Also, depending on the load, the connection of
the plug and receptacle is the weakest part of the circuit and is
the most likely section to overheat. Therefore, adding
additional plugs and receptacles increases the chance for
Do coffee pots, toaster ovens and
other small appliances have to have an auto shut-off feature? Where
is this written?
The answer to this question is no, but
all small appliances should be located on non-combustible surfaces
and away from flammable materials such as paper towels, drapes,
etc. UL and most manufacturers of these type appliances advise that
all counter-top heat-generating devices be unplugged when not in
use. A way to assure the equipment is not energized would be to
use a spring-wound count-down timer to energize the equipment.
Am I allowed to use a space heater in
my office? What are the requirements?
The requirements for space heaters can
be found in SBMS in the
Fire Safety Subject Area.
Basically the requirements are: a) that
the electrical circuit be evaluated by Plant Engineering, b) UL
listed, c) have tip-over protection, d) users instructed in safe
operation (unplugged when not in use, keep combustibles at least 3
feet away, and ensure the unit is off at the end of day) and d)
Plant Engineering attaches a review label to the heater
demonstrating that the equipment, power supplies, and arrangements
If my space heater trips a circuit
breaker, can I reset it?
Only if trained and
only if you know why the breaker tripped, otherwise contact your
Building Manager or Plant Engineering.
Where can I find suppliers of Electrical Safety
Electrical Safety Equipment can be purchased from
any Safety and Industrial Supplier, such as MSC, LSS, Grainger, etc. For
testing voltage rate gloves you can contact Bodine Business Products (610) 827-0138,
Salisbury (800) 549-1477, or Brenco Powerline Tools (800) 247-5442.
Where do I find the electrical safety
Electrical Safety Subject Area in SBMS, if you have any
questions or concerns contact the Laboratory Electrical Safety
What is a live part?
Energized conductive components. A live
part could be a terminal, screw, exposed conductor, or any part of a
circuit that a person could touch and get a shock.
What is a GFCI and when is it
A GFCI (ground fault circuit
interrupter) constantly monitors electricity flowing in a circuit,
to sense any loss of current to ground. If the current flowing
through the hot wire differs by a small amount from that returning
in the neutral, the GFCI quickly switches off power to the circuit.
The GFCI interrupts power fast enough to prevent a lethal dose of
electricity. You may receive a painful shock, but you should not be
electrocuted or receive a serious shock injury. A GFCI may be a
duplex receptacle, a circuit breaker, attached to an extension cord,
or a temporary plug-in adapter.
GFCIís are required in different
locations for houses and for industrial locations. In houses they
are required in: 1) bathrooms, 2) garages and accessory buildings,
3) outdoors, 4) crawl spaces, 5) unfinished basements, 6) Kitchens,
7) 6 ft from Laundry, utility, and wet bar sinks, and 8)
boathouses. In other than dwelling units: 1) bathrooms, 2)
commercial and institutional kitchens, 3) rooftops, and 4)
outdoors. The National Electrical Code also has other requirements
in specific sections of the Code like commercial garages, swimming
pools, decorative fountains, etc.
Who is allowed to flip breakers on
At BNL, only persons
who are trained and allowed by their Department/Division. If you
donít know if you are allowed to operate circuit breakers, then you
probably are not. Contact your Building Manager or ESH
Coordinator for help.
When is homemade electrical equipment
Only when it has been approved by the
BNL Authority Having Jurisdiction. If you want to bring any
electrical equipment onsite that is not listed by a Nationally
Recognized Testing Laboratory (UL, Factory Mutual, etc. see the
Electrical Safety Subject Area for full list of NRTLís) you must
have it approved by a BNL Electrical Equipment Inspector.
Contact your Building Manager or ESH Coordinator for help.
Last Modified: May 10, 2012
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