Transcript Electrical shock

FHM TRAINING TOOLS
This training presentation is part of FHM’s
commitment to creating and keeping safe
►►►
workplaces.
Be sure to check out all the training programs
that are specific to your industry.
These materials have been developed based on applicable federal laws and regulations in place at the time the materials were created. The program
is being provided for educational and informational purposes only and does not constitute and is not intended to provide OSHA compliance certification,
regulatory compliance, a substitute for any "hands on“ training required by applicable laws and regulations, or other legal or professional advice or
services. By accessing the materials, you assume all responsibility and risk arising from the use of the content contained therein.
©2010 Grainger Safety Services, Inc.
Electrical Safe Work Practices
for Unqualified Workers
►►►
These materials have been developed based on applicable federal laws and regulations in place at the time the materials were created. The program
is being provided for educational and informational purposes only and does not constitute and is not intended to provide OSHA compliance certification,
regulatory compliance, a substitute for any "hands on“ training required by applicable laws and regulations, or other legal or professional advice or
services. By accessing the materials, you assume all responsibility and risk arising from the use of the content contained therein.
©2010 Grainger Safety Services, Inc.
Learning Objectives
Objectives:
►
Be familiar with the information
required by the OSHA’s standard
for Electrical Safety-Related
Work Practices, Code of Federal
Regulations as Title 29 Part
1910.332
►
Possess information necessary
to work safely with, on, or near
electrically-powered equipment
Agenda
Presentation agenda:
►
Overview
►
Basics of electricity
►
Hazards of electricity
►
Safe work practices
►
Your responsibilities
►Section 1
Overview
Electrical Safety
Electricity facts:
► Electrical
generation is less than
150 years old
► Average
of one worker electrocution
daily
► Major
cause of home fires
Electrical Safety
OSHA standards:
► Requires
safe work practices and protective
equipment when electric hazards are present
person – familiar with electrical equipment
and its hazards
► Qualified
► Covers
daily use of electrically-powered equipment
Employee Training
OSHA requirements:
► Qualified
employees may work on
energized systems
► Required
training:
– Distinguishing exposed live parts
– Determining nominal voltage
– OSHA specified clearance
distances
►Section 2
The Basics of
Electricity
Electrical Terminology
Basic terms:
► Current
► Circuit
– the movement of electrical charge
– the flow of electrical charge
► Resistance
► Voltage
– opposition to current flow
– measure of electrical force
Electrical Terminology
More terms:
– substances with little
electrical resistance
► Conductors
– substances with high
electrical resistance
► Insulators
► Grounding
to the earth
– conductive connection
Basics of Electricity
The basics:
► Electricity
is the flow of electrons
through a conductor
► Current
is the flow and measured in
amps
► Current
only flows within a complete
circuit
► Current
flows due to voltage
► DC
is constant voltage
► AC
is alternating current
►Section 3
The Hazards of
Electricity
Injuries Related to Electricity
Main types of injuries:
– death due to
electrical shock
► Electrocution
► Electrical
► Burns
shock – non-fatal shocks
– most common
– from muscle spasms due to
shocks
► Falls
Electrical Shock
Facts on shocks:
► Occur
when a part of the body comes in contact
with an electrical circuit
► Small
currents and low voltages can still be fatal
► Severity
of shock depends on:
– Path through the body
– Amount of current
– Length of time in circuit
►Section 4
Safe Work
Practices
Electrical Safe Work Practices
Categories of practices:
► Grounding
► Electrical
protective devices
► Guarding
energized parts
► Proper
use of cords
► Maintaining
► Clothing
distances
and jewelry
Proper Grounding
Grounding is a physical connection to the earth:
► Grounding
paths must be permanent and
continuous
or System Ground – primarily designed to
protect machines and tools against damage
► Service
Ground – provides a
path from the tool or machine for
current to flow to the ground
► Equipment
Proper Grounding
Hand-held tools must be:
► Equipped
with three-wire cord with
ground
► Plugged
into a grounded receptacle
► Double-insulated
► Powered
by a low-voltage isolation
transformer
Electrical Protective Devices
Types of protective devices:
– will be destroyed before
considerable damage can be dealt
► Fuses
breakers – a set of contacts
opens the circuit
► Circuit
► Ground-fault
circuit-interrupters
Electrical Protective Devices
Ground-fault circuit-interrupter
(GFCI):
► Detect
leakage currents
► Matches
current going to a device
against current returning
down within 1/40th of a
second when fault is detected
► Shuts
► Able
to detect loss of current due
to a person who is being shocked
Guarding Energized Parts
Equipment operating at 50 volts or
more should be isolated by:
► Protective
cabinet or enclosure
► Permanent
► Elevation
► Must
partitions
above working surface
be conspicuously marked
Guarding Energized Parts
All wiring needs to be protected:
► Junction
boxes, outlet boxes,
switches and fittings must have
approved covers
► Unused
► Wiring
openings must be closed
needs to be intact and
shielded
Flexible (extension) Cords
Causes of cord damage:
► Aging
► Door
or window edges
► Staples
or fastenings
► Abrasions
► Activities
in the area
Flexible (extension) Cords
Cords may not be used:
► As
a substitute for fixed wiring
► Where
run through holes in walls, ceilings or floors
► Where
run through doorways or windows
► Where
attached to
building surfaces
► Where
concealed behind
walls, ceilings, or floors
Maintaining Distances
Maintaining distances is a necessity:
► Overhead
power lines are not insulated
► Unqualified
workers are
required to maintain at least
10 foot clearance
► Fallen
overhead wires should
never be touched
► Ladders
should not be
used near power lines
Clothing and Jewelry
Conductive clothing and jewelry:
► Watch
bands
► Bracelets
► Rings
► Key
chains
► Necklaces
► Metalized
aprons
► Cloth
with conductive thread
► Metal
headgear
Clues that Electrical Hazards Exist
Clues:
► Tripped
circuit breakers
► Blown
fuses
► Warm
wiring
► GFCI
shuts down the circuit
► Damaged
► Wiring
insulation
pulling loose
►Module 5
Your
Responsibilities
Your Responsibilities
Your responsibilities include:
► De-energizing
► Maintain
► Be
equipment before inspecting
and inspect electrical tools
aware of your surroundings
► Inspect
and properly use extension cords
► Wear
personal protective equipment
when necessary
► Maintain
10 foot clearance from overhead
power lines