One module of a small-business course on preventing electrical injuries. An archived deck: check it against the current standard before teaching from it.
Slide text
· 37 slides · by National Safety Council
The words on each slide as the author wrote them, read from the file by software so they can be searched. Layout, pictures and tables are not shown here: the slides above and the download are the original.
- Slide 1
Module
- Introduction to
- Electrical Safety
- Slide 2
Module Objectives
- Recognize key statistics relating to electrical
- Recognize OSHA injuries.
- regulations and other standards relating to electrical
- safety.
- Understand
- basic
- electrical terminology.
- Slide 3
Module Objectives
- Identify the four types of injury relating to electrical
- incidents. Understand key facts relating to electric shock.
- Understand the basic facts of electricity.
- Slide 4
Module Objectives
- Understand Ohm’s Law and describe how the terms current, voltage and resistance relate to Ohm’s
- Law.
- Recognize the effects of
- electricity on the human body.
- Slide 5
Electrifying
- Statistics
- From 1992-2002, there were
- 3,378 deaths from on-the-job electrical injuries.
- That’s 4.7% of all occupational deaths.
- That’s almost one death per day!
- Electricity is the 4 th leading
- Slide 6
- Electrifying
- Contact Statistics
- with overhead
- power lines was the leading cause of electrocutions, causing 42% of the deaths.
- The second leading cause of electrocutions was failure to properly de-
- Slide 7
Electrifying
- Statistics
- The third
- most common
- cause was contact with electrical components mistakenly thought to be de-energized.
- Contact with buried, underground power lines caused 1% of the
- Slide 8
Electrifying
- Non-fatal Statistics
- injuries were also
- high, with 46,598 from 1992 through
- 2002
- 36% were
- caused
- by contact
- with the electric current of a machine or tool.
- 34% were caused by contact with wiring or transformers. 2% were caused by contact with buried, underground
- Slide 9
OSHA 29 CFR 1910, Subpart I
- OSHA 29 CFR 1910, Subpart P
- OSHA 29 CFR 1910, Subpart S
- OSHA 29 CFR 1910.147
- OSHA 29 CFR 1910.333
- Slide 10
NFPA 70E
- Safety related work practices
- Safety related maintenance requirements
- Safety requirements for special equipment Installation safety requirements
- Slide 11
NFPA 70E
- Handbook
- A supplement
- to
- the NFPA 70E standard
- Gives step-by-step instructions for how to implement the standard Provides the thought process and rationale for
- Slide 12
What they all Do
- OSHA is the SHALL
- NFPA 70E standard is the HOW
- NFPA 70E handbook is the STEP-BY-STEP
- Slide 13
Qualified Person
- One who has received training in and has demonstrated skills and knowledge in the construction and operation of electric equipment and installations and the hazards involved.
- Slide 14
Important Note
- This program does not meet the requirements for a qualified person. It is intended to raise your awareness of electrical safety.
- Slide 15
Arc Flash
- Slide 16
Types of Electrical
- Injury
- Elect
- El k
- rocut
- io n
- Fal ls
- Slide 17
Rules of Electrical
- Action
- Electric current won’t flow until there is a complete loop.
- Electric current always tries to return to its source.
- When current flows, work can be accomplished.
- Slide 18
How Shock Occurs
- The body comes into contact with wires in an energized circuit.
- The body comes into contact with one wire of an energized circuit and a path to the ground.
- The body comes into contact with a “hot” metallic part that
- Slide 19
Severity of Shock
- Three factors
- The path of the current through the body.
- The amount of current flowing through the body. The length of time the body is in the circuit.
- Slide 20
Basic Facts of Electricity
- ELECTRICITY
- ELECTRONS IN MOTION
- Slide 21
Basic Facts of Electricity
- Flow of Electricity
- Flow of CURRENT Water
- Flow of electrons
- Measured in amps
- Flow of liquid
- Measured in gallons per minute (gpm)
- I = amps
- Slide 22
FORCE Water
- Basic Facts of Electricity
- Flow of Electricity
- Measured in voltage
- V or E = volts
- Flow of
- Measured in pounds per square inch (psi)
- Slide 23
Basic Facts of Electricity
- Flow of
- Flow of Electricity RESISTANCE Water
- Electrical resistance to flow is measured in ohms
- R = resistance
- Water resistance to flow is measured as friction or baffles
- Slide 24
Ohm’s Law
- George Simon
- Ohm
- 1789-1854
- German
- Physicist
- A mathematical formula that enables the measurement of electric current moving
- through
- Volts (V) = Amps (I) X conductive
- body
- Resistance
- (R)
- V = IR
- 1 volt = 1 amp X 1 ohm of resistance
- Slide 25
A Visual Way to Remember
- Slide 26
Solution
- 1.Since we know voltage (V) and resistance (R), which version of the formula should we use?
- I =
- V/R
- Slide 27
plug in?I =
- Solution
- 2.Now which numbers do we
- 120/1,00
- 3.How many
- amps?
- I = .12
- amps
- 4.How many milliamps
- (mA)? I = 120
- milliamps
- Slide 28
The Human Body Resistance Model
- Body Part
- Resistance
- Dry, intact skin
- 100,000-600,000 ohms
- Wet skin
- 1,000 ohms
- Within the body
- 400 ohms
- Ear to ear
- 100 ohms
- Slide 29
Effects of Electricity
- Depend
- On:
- Strength of current.
- Duration of contact. Body mass.
- Gender of person. Moisture on the body. Path of the current.
- Slide 30
- Photo courtesy of Schneider Electric
- Slide 31
- Photo courtesy of Schneider Electric
- Slide 32
- Photo courtesy of Schneider Electric
- Slide 33
What the Project
- Manager
- Felt
- 1.The drill had 120 volts.
- 2.The project manager’s dry skin had a resistance of 100,000
- 3.The flow ohms.
- into the project
- manager’s hand was
- 120 volts/100,000 ohms, 0.0012 amps, or 1.2 milliamps.
- Slide 34
What the Apprentice Felt
- 1.The drill had 120 volts.
- 2.The apprentice’s wet skin had a resistance of 1,000 ohms.
- 3.The flow into the apprentice’s hand was 120 volts/1,000 ohms, 0.12 amps, or 120 milliamps.
- Slide 35
Facts About Lower
- Amperage
- A small circuit in your home carries 12-16 amps of current.
- That equals 12,000 to 16,000 milliamps.
- As we’ve learned, as little as 120 milliamps can cause death.
- Low amperage/voltage circuits are dangerous!
- Slide 36
NIOSH Low Voltage Study
- 600 v
- 440-480 v
- 8%
- 22%
- 110-120 v
- 34%
- 270-277 v
- 220-240 v
- 16%
- 20%
- That’s over 1 in 3 deaths at 120
- or less!
- Slide 37
Action Plan
- Action
- Potential Barriers
- Overcoming the Barriers
