Lesson Plan
Course Title: Construction Technology
Session Title:
Electrical Safety and Grounding Essentials
Performance Objective:
Upon completion of this assignment, the student will be able to apply the basic safety
rules and procedures for working on electrical systems.
Specific Objectives:
 Demonstrate safe working procedures in a construction environment.
 Identify electrical hazards and how to avoid or minimize them in the workplace.
 Describe conditions likely to affect severity of electrical shock.
 Describe steps for helping a shock victim.
 Cite working principles for electrical grounding.
 Explain equipment grounding and system grounding.
 Define bonding and explain how it is done.
 Explain operation of GFCIs and where they are used.
Preparation
TEKS Correlations:
This lesson, as published, correlates to the following TEKS. Any changes/alterations to
the activities may result in the elimination of any or all of the TEKS listed.

130.55. Advanced Building Maintenance Technology
(b) Students will gain advanced knowledge and skills in safety, Occupational
Safety and Health Administration (OSHA) standards, safety devices in
electrical circuits, maintenance of electrical and heating, ventilation, and
air conditioning (HVAC) systems, and concepts of historic preservation.
(2) Students will know electrical safety regulations and safety guidelines
(a) demonstrate safe working procedures during building maintenance;
(b) explain the purpose of the OSHA and how to promote safety on site;
(c) identify electrical hazards and how to avoid or minimize them on site; and
(d) explain safety issues concerning lockout and tagout procedures, personal
protection using assured grounding and isolation programs, confined
space entry, respiratory protection, and fall protection.
Interdisciplinary Correlations:
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Instructor/Trainer
References:
1. Modern Residential Wiring, Harvey N. Holzman ISBN 1-56637-913 - X
2. House Wiring Simplified, Floyd M. Mix ISBN 1-56637-899-0
3. NCCER Wheels of Learning Prentice Hall ISBN 0-13-018904-9
4. Electrical Curriculum Connecticut State Department Of Education Robert Martin
5. DHHS Electrical Safety (NIOSH) Publication # 2002-123
6. Agriculture Core Curriculum Electrical Safety (CLF2652) Delmar Publishers
Instructional Aids:
1. Electrical Safety PowerPoint Presentation.
2. Ohm;s Law Handout
3. Electrical Safety Exam.
4. Electrical Safety Exam Key.
Materials Needed:
None
Equipment Needed:
1. Infocus Projection (or similar.)
2. Computer with PowerPoint Software.
Learner
1. Pen
2. Paper
Introduction
Introduction (LSI Quadrant I):
1. Relate Personal Experiences.
2. Stress the importance of having a good safety attitude.
3. Show safety Videos and Power Point Presentations of actual hazardous events
and accidents.
Outline
Outline (LSI Quadrant II):
Given a list of potential electrical and other worksite dangers, students will be able to
recognize the dangers and know what appropriate action should be taken.
Given OSHA Hazardous Communication guidelines, students will know how to identify,
obtain, develop and communicate hazardous exposure on the job site
1. Demonstrate and develop a worksite survey evaluation.
2. Demonstrate proper procedures for identification of potential dangers.
3. Demonstrate the need for the utilization of protective corrective action.
4. Develop and assess a list of potential dangers.
5. Recognize what equipment must be tagged and locked out. After recognizing
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the equipment students will apply the proper procedures in applying a tag and
lockout device according to OSHA guidelines.
6. Identify shock and fire hazards associated with electric current.
a. Shock and fire are hazards associated with electric current.
b. Shock refers to the body's reaction to the passing of electrical current
through it.
c. Shock occurs from a fall in blood pressure resulting in a decrease of
blood supply, and therefore oxygen, to the brain.
d.The increasing levels of electrical shock caused by increasing amperage
makes it clear that voltage is not the killer, rather amperage is.
e. Shock hazard from electrical current is expressed in milliamperes. One
millampere (commonly called a "milliamp") is equal to one thousandth
of an ampere, i.e., A/1000 where A is the electrical current in amperes.
f. Fire may occur when electrical conductors overheat or when a spark is
produced when an electric current jumps an air gap between
conductors.
7. Describe the procedures used to aid a victim of electrical shock.
a. Shut off the power immediately.
b. Do not move victim but give medical assistants
c. If power can not be shut off, use non-current objects to remove victim
for current carrying equipment.
8. Discuss the theory of zero potential to ground.
9. Explain all code articles pertaining to grounding.
10. Demonstrate proper installation of grounding electrodes.
11. Explain electrolytic grounding system.
12. Describe proper grounding techniques.
13. Demonstrate ground testing.
14. Discuss the principles and theory for both class “A” and “B” ground fault circuit
interrupters.
15. Demonstrate how a GFCI operates.
16. Exhibit how to identify both classes of GFCI protection.
17. Discuss the importance of installing GFCI devices.
18. Apply all safety requirements to ensure a safe and reliable GFCI circuit.
19. Construct a proper GFCI protected circuit.
Application
Guided Practice (LSI Quadrant III):
Teacher will demonstrate and establish a written program, by conducting a survey of
facilities to determine locations of all hazardous or unsafe conditions.
Independent Practice (LSI Quadrant III):
Student will complete a safety checklist of his or her own home's electrical system. The
local fire department can provide a good checklist.
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Summary
Review (LSI Quadrants I and IV):
Check for Knowledge
1. List 8 safety rules that should be observed when working with
electrical equipment.
2. List three locations where GFCIs are required.
3. Explain what is meant by:
a) Ground fault.
b) Short circuit
Evaluation
Informal Assessment (LSI Quadrant III):
Instructor will observe students in lab setting to insure a safe working environment.
Formal Assessment (LSI Quadrant III, IV):
Students must successfully complete electrical safety exam.
Extension/Enrichment (LSI Quadrant IV):
Observe the following general safety practices in doing all electrical work.
1. Avoid damp working areas. Never handle electrical equipment with wet hands
or while standing in a wet or damp place.
2. Protect each circuit. Be certain that each circuit is protected with either a circuit
breaker or a fuse of proper amperage.
3. Ground each circuit properly. Each circuit must have a ground (neutral) wire
and a grounding wire to be properly grounded.
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Ohm’s Law Exam
Name ________________________________ Date_______________
Circle the best answer for each statement.
1. Voltage can be defined as:
A. Electrodynamic force
B. Electropotential force
C. Electrochemical force
D. Electromotive force
2. Current is the
A. Build up of electrons
B. Flow of electrons
C. Division of electrons
D. Passing of electrons
3. Resistance is the ___________ of/to current flow.
A. Opposite
B. Opposition
C. Result
D. Reverse
4. Voltage compares to __________ in a gas system.
A. Flow of gas
B. Restriction of gas flow
C. Pressure
D. Orifice effect
5. Current compares to ________ in a liquid piping system.
A. Orifice effect
B. Flow of product
C. Pressure pushing the product
D. Friction of the inside pipe wall
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6. Resistance compares to ___________ in a gas or liquid piping system.
A. Build up of pressure
B. Flow of product
C. Orifice effect
D. Pipe’s outside diameter Text.
7. Mathematically, Ohm’s Law takes on which form?
a. E = I/R
b. I =E/R
c. R = E x I
d. I = R/E
Solve Problems for an Unknown Quantity (Show your work)
1. A circuit is drawing a current of 2 amps, and the resistance is 60 Ohms. What is the
voltage?
2. A 460- volt circuit operates at 100 amperes. What is the resistance of the circuit?
3. What is the resistance in a circuit drawing 4 amps through a potential of 240 volts?
4. Apply the appropriate formula to answer each problem:
Volts
Ohms
Amps
a.
b.
c.
230
440
120
12 =
20 =
40 =
Volts
d.
e.
f.
240
12
24
4 =
5 =
8 =
Ohms
g.
h.
i.
j.
Amps
40
35
100
15
Volts
10 = _________
15 = _________
2.4 = _________
10 = _________
Amps
________
________
________
Ohms
________
________
________
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Ohm’s Law Exam KEY
Name ________________________________ Date_______________
Circle the best answer for each statement.
1. Voltage can be defined as:
A. Electrodynamic force
B. Electropotential force
C. Electrochemical force
D. Electromotive force
2. Current is the
A. Build up of electrons
B. Flow of electrons
C. Division of electrons
D. Passing of electrons
3. Resistance is the ___________ of/to current flow.
A. Opposite
B. Opposition
C. Result
D. Reverse
4. Voltage compares to __________ in a gas system.
A. Flow of gas
B. Restriction of gas flow
C. Pressure
D. Orifice effect
5. Current compares to ________ in a liquid piping system.
A. Orifice effect
B. Flow of product
C. Pressure pushing the product
D. Friction of the inside pipe wall
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6. Resistance compares to ___________ in a gas or liquid piping system.
A. Build up of pressure
B. Flow of product
C. Orifice effect
D. Pipe’s outside diameter Text.
7. Mathematically, Ohm’s Law takes on which form?
a. E = I/R
b. I =E/R
c. R = E x I
d. I = R/E
Solve Problems for an Unknown Quantity (Show you work)
1. A circuit I s drawing a current of 2 amps, and the resistance is 60 Ohms. What is the
voltage?
E=IxR
E = 2 x 60 = 120 volts
2. A 460- volt circuit operates at 100 amperes. What is the resistance of the circuit?
R = E/I
R = 460/100 = 4.6 ohms
3. What is the resistance in a circuit drawing 4 amps through a potential of 240 volts?
R = E/ I
R = 240/4 = 60 ohms
4. Apply the appropriate formula to answer each problem:
E/R
Volts
Ohms
Amps
a.
b.
c.
E/I
Volts
d.
e.
f.
IxR
Ohms
g.
h.
i.
j.
230
440
120
12 =
20 =
40 =
Amps
Ohms
240
12
24
4 =
5 =
8 =
Amps
Volts
40
35
100
15
10 =
15 =
2.4 =
10 =
20
22
3
60
2.4
3
400
525
240
150
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