Electrical safety is an important issue that can prevent fatalities and injuries. Each year, contact with overhead power lines results in deaths and property damage. Working near electricity puts many workers at risk, including equipment operators, emergency responders, and those on ladders or scaffolds. Even small amounts of electricity can cause harm, with just 75mA potentially causing death. Proper safety training and coordinating work with utilities can help prevent electrical accidents.

1. Electrical Safety
By
Autry Technology Center

2. You shall be able to identify:
 The injuries and fatalities while working near
electricity.
 Basic electrical principles.
 Workers at risk.
 Basic electrical hazards. Safe work practices
associated with electricity.

3. Crane contacts electrical lines;
causes fire; tires begin to burn

4.  Each year contact with overhead power lines
result in fatalities, serious injury and property
damage.
 Unintentional contact with overhead power lines
resulted in the following:
Based on accident statistics in one state
 19 serious accidents from July 1999
through September 2005.
 16 fatalities.
Based on national statistics (NSC–2004)
 309 fatalities occurred from 1999 to 2001.

5.  These statistics only represent facts
that have been reported to these
agencies; the actual number of fatalities
and suffering are far greater.

6. Electricity - The Dangers
 About 5 workers are
electrocuted every week
 Causes 12% of young
worker workplace deaths
 Takes very little electricity
to cause harm
 Significant risk of causing
fires

7.  Fact: an electrical
arc generates
temperatures in
excess of 35,000
degrees F.
 This is hot enough
to vaporize steel.

8. Electrical Shock Injury;
Note entry and exit point
 These accidents can
be prevented with
improved supervisor
and worker safety
training and better
coordination of work
with all utilities
involved.

9. Same injury a few days later

10. Exit point on bottom of foot

12. At-Risk Workers
 Equipment operators of mobile
equipment, dump trucks, drill rigs, cranes, etc.
and employees who work around this equipment
 Emergency service personnel who respond to
car crashes involving power poles and overhead
lines, downed power lines, respond to fires
involving electrical lines near structures
 Employees working from ladders
 Employees working with electrical equipment

13. At-Risk Workers
 Employees working from roofs where
power lines enter building
 Employees who work from scaffolds
 Employees who work from Man lifts or
bucket trucks around power lines
 And Any employee who is near overhead
power lines for any reason such as tree
trimmers, highway workers, forklift
operators, etc.

14. Electrical Shock
An electrical shock is received when electrical
current passes through the body.
You will get an electrical shock if a part of your
body completes an electrical circuit by…
 Touching a live wire and an electrical ground, or
 Touching a live wire and another wire at a
different voltage.

15. Electrical Harm
Estimated Effects of AC Currents
(U.S. Standard 60 Hz)
1 milliamp
(mA)
Barely perceptible
16 mA Maximum current an average
man can grasp and “let go”
20 – 30 mA Paralysis of respiratory
muscles
100 mA Ventricular fibrillation
threshold
2 Amps Cardiac standstill and internal
organ damage
15/20/30
Amps
Common U.S. household
breakers
PATH:
Harm is
related to
the path by
which
current
passes
through
the body.

16. Dangers of Electrical Shock
 Currents greater than 75 mA*
can cause ventricular
fibrillation (rapid, ineffective
heartbeat).
 Will cause death in a few minutes
unless a defibrillator is used.
 75 mA is not much current – a
small power drill uses 30 times
as much current.
Defibrillator in use

17. Fundamentals of Electrical
Hazards
 To flow electricity must have a complete path.
 Electricity flows through conductors
water,
metal,
the human body
 Insulators are non-conductors.
 The human body is a conductor.

18. Electrical Injuries
There are four main types of electrical injuries:
 Direct:
 Electrocution or death due to electrical shock
 Electrical shock
 Burns
 Indirect - Falls

19. Burns
 Most common shock-
related injury.
 Occurs when you touch
electrical wiring or equipment
that is improperly used or
maintained.
 Typically occurs on hands.
 Very serious injury that
needs immediate attention

20. Hit live wire changing a light
ballast; lost right index finger

25. High Voltage Electricity Follows the
Path of Least Resistance to Ground
Fact:
 High Voltage Electricity Follows all Paths to
Ground

26. Worker subjected to arc flash

27. Fire resistant shirt

29. Electrical Damage to the Body
 If you touch a power
line, electricity will
attempt to travel
through your body
 When electricity travels
through the body, it
heats up and burns
body tissue internally
 Electricity leaves the
body violently, causing
burns or even blowing
an exit hole

30. The Sad
Reality- this
victim
contacted an
overhead
power line
while working
from an aerial
bucket

31. Myths
Fact:
 Possibly Dead Wrong! Electricity Travels at the
speed of light, 186,000 miles per second.
 If you touch another person that is in contact
 with a high voltage wire you will instantly
 become part of the electrical circuit.
You Can Safely Shove a Person Away From
Contact With an Energized Power

32. Car and Truck Tires Are Made of Rubber and Are
Non-Conductive
Fact:
 Tires contain Carbon Black. Carbon Black is a
conductive material used to make the tires conductive
for a better radio signal and to make them last longer.
 If an overhead electrical line falls upon your vehicle stay
on or inside the vehicle if at all possible.
 If you must leave your vehicle do not touch the vehicle and
ground at the same time.
 Jump clear and Keep both feet together and hop away.
Myths

33. I Can Safely Use a Tree Limb To Move an
Overhead Powerline
Fact:
 Tree limbs are conductive. Fresh tree limbs are
very electrically conductive due to the moisture
content.
 High voltage electricity will conduct through most
items that have contamination or moisture.
Myths

34. Overhead Powerlines Laying on the Ground Are
Safe To Be Near.
Fact:
 Just because a power line is laying on the ground
does not mean it is not energized.
 Always consider downed power lines live!
 High voltage electricity can enter the ground from
the power line.
 This can create different electrical potentials near the
wire that could cause electrocution by contact through
your footwear.
Myths

35. I Can Look-Up and Estimate the Distance to The
Powerline.
Fact:
 Few people have the ability to judge vertical
distance accurately.
 Don’t take a chance with your safety and the
safety of those working around you.
 Call the owner of the powerlines at least 72
hours prior to working within 50 feet of
energized overhead power lines.
Myths

36. I’ve Been Shocked by Electricity Before, So I
Know What Electricity Will Do.
Fact:
 Unless you have seen the destructive
power of High Voltage Electricity first hand
you have no idea what it can do to
material, objects and to people compared
to household voltages.
Myths

37. A Powerline Falls Across Your Vehicle, You
Should Not Try to Drive Away.
Fact:
 You should try to drive away if at all possible.
 If your vehicle will not start stay inside and warn
others to stay away until an electrical line worker tell
you it is safe to leave the vehicle.
Myths

38. Scaffold Too Close to Power Lines
• The possibility of
electrocution is a
serious
consideration when
working near power
lines.
• Check the clearance
distances listed in
the OSHA
standards.

39. Ladder Too Close to Energized
Electrical Equipment
If using ladders where
the employee or the
ladder could contact
exposed energized
electrical equipment,
they must have
nonconductive siderails
such as wood or
fiberglass.
This is an unsafe condition

40. It’s up to you to prevent contacts
with electricity.

41. Don’t Put Your Life on the Line!