Electric Safety
Electric utilities place high priorities on providing their workers
a safe environment for power line construction and maintenance. In
addition, regulatory agencies such as the Occupational Safety and Health
Administrations (OSHA) and the Institute of Electrical and Electronics
Engineers (IEEE) provide fundamental rules to create a safe working
environment . These rules are published in OSHA standards and the
National Electrical Safety Code (NESC).
This course covers the foundations of personnel safety for utility work,
including:
Transmission line maintenance and construction, including energized and
de-energized works
Applicable OSHA standards, IEEE standards, and the NESC are
discussed in conjunction with each topic. The course provides the
engineering justifications (modeling and analysis) of the standards and
safety codes.
Several real-world cases are presented, studied, and analyzed in
this course. In addition, some of the tools used to analyze the worksite
hazards and to test the safety procedures are discussed.
Participants will understand the foundations of electric safety.
They will be able to identify hazards at the worksite, and will be able
to design effective safety procedures at worksites.
Who should attend?
Utility engineers
Electric safety equipment manufacturing workers and engineers
Attorneys involved in electric safety issues
Topics Covered
Introduction to Electric Safety
Fundamentals
Alternating currents
Three-phase systems
Power line conductors
Power line towers
Main Equipment in Power Systems
Transmission grids
Substations and switch yards
Protection, measurements and control equipment
Electromagnetic Coupling
Electromagnetic field
Induced voltage due to electrical field
Induced voltage due to magnetic field
Computation of induced voltage
Case studies
Human tolerance to Electricity
Biological effects of electricity
Safe limits of currents and voltages
Resistance of the human body
Grounds and grounding systems
Definition of grounds
Ground resistance of objects
Measuring the ground resistance of objects
Ground resistance of people
Hazards of Electricity
Step potential
Touch potential
Worksite Hazards
Identifying hazards
Isolation, insulation and grounding techniques
Concept of equipotential zone
Regulations and standards
De-energized work
De-energizing work site
Hazards of de-energized equipment
Grounding
Definition of effective grounds
Main equipment used as temporary grounds
System grounding
Local grounding
Traveler ground
Creation of the equipotential zone
Protection of all workers at the worksite (on tower, inside the boom,
and on the ground)
Real world case studies
Safety dilemma
Key standards
Live work
Hazards
Basic safety concepts
Live work tools
Minimum approach distance
Exceptions for bare hand work
Aerial work
Case studies
Key standards and practices
Electric field under Power Lines
Hazards of induced voltage
Electric field strength
Industry rules on electric field strength
Minimum clearance rules
Case studies
Atmospheric Discharges
Characteristics of lightning
Traveling of lightning along power lines
Protection of system against lightning
Protection of personnel and equipment
Stray Voltage
Neutral versus ground
Grounding practice
Sources of stray voltage
Elimination of stray voltage