- Identify the regulations pertaining to electrical safety
- Define various electrical terms
- Calculate voltage and current

Regulations and Electricity Basics
Regulations and Electricity Basics
Electrical Work Practices are Regulated
The two governing agencies that regulate electrical work include:
These regulations and standards work to minimize electrical hazards in the workplace due to unsafe acts, equipment, installations, and environmental conditions. OSHA's electrical standards are designed to protect employees exposed to dangers such as electric shock, electrocution, fires, and explosions.
Note: This training course does not certify individuals in electrical safety; rather the intent is to meet the OSHA and NFPA technical training standards on the hazards associated with working with and around electricity.
Regulations and Electricity Basics
Qualified and Unqualified Workers
In order to work with electricity you must be qualified.
Qualified Persons: are trained and knowledgeable of the construction and operation of equipment or a specific work method and are trained to recognize and avoid the electrical hazards that might be present with respect to that equipment or work method.
To be considered Qualified, you must:
Regulations and Electricity Basics
Qualified and Unqualified Workers
Unqualified persons:
Unless you meet the "Qualified Persons" requirements described in the previous screen you are considered Unqualified. Do not approach energized exposed live parts under any circumstances if you are considered an unqualified person.
Unqualified personnel who work near energized electrical equipment still need some electrical safety training.
Note: If you are unqualified you may only work on or near electrical equipment under the direct supervision of a Qualified Person.
Unqualified personnel must:
Regulations and Electricity Basics
What is Voltage?
Voltage (V) can be thought of as the force or pressure of electricity.
It is also known as potential.
This potential or force is measured in volts (V).
There are three classifications:
Regulations and Electricity Basics
What is Current?
Current (I) can be thought of as the flow of electricity through a conductor or wire. It is a measure of the rate of flow of the number of electrical charges passing a point in a second.
Current actually does the work of electricity; for example, the light bulb illuminates as current flows through it.
Current is measured in amperes and informally known as amps (A).
Regulations and Electricity Basics
Regulations and Electricity Basics
What is Resistance?
Resistance (R) is the property in all materials that impedes current flow and is measured in ohms .
All materials have resistance, but to varying degrees.
The more resistance that a material has, the less current it will allow to flow through it.
Electricity travels better through some materials (conductors) and poorly or not at all through others (insulators).
Steel, copper, aluminum, silver, iron, and other metals are good conductors because electricity passes through them easily.
Non metallic materials like wood, rubber, plastic, glass, porcelain, and fiberglass are good insulators as electricity has a difficult time passing through them.
Regulations and Electricity Basics
Circuits
A circuit is the path through which electricity (current) flows.
Current (I) can only flow through a completed circuit.
Anything that can conduct electricity could become part of a circuit including electrical and non-electrical components, such as wires, switches, resistors, batteries, outlets, hand tools, the human body, the earth, jewelry, etc.
Remember:
Regulations and Electricity Basics
How Voltage, Current, and Resistance are related.
Ohm's Law
Voltage=Current multiplied by ResistanceThere are two important things to realize from these equations:
These two facts become significant when the human body becomes part of an energized circuit.
Summary
In this lesson you learned electricity basics. Let's review the key points from this lesson.Checkpoint
A Qualified Person must:Checkpoint
Voltage can be thought of as the flow of electricity through a conductor or wire.Electricity Hazards
Electricity Hazards
Electricity Hazards
Some people have been shocked by electricity and lived to tell about it. Lucky people. Even small amounts of electricity can be deadly.
Electric shock occurs when any part of the human body becomes part of a circuit.
The human body has a natural resistance which will limit the amount of current that can flow through the body, but it is still a relatively good conductor.
Shock severity depends on three things:
Electricity Hazards
Electric shock occurs when any part of the human body becomes part of a circuit.
Electric current, which is measured in amperes, is the most important physiological variable which determines the severity of an electric shock.
Click on the milliamps (mA) to view the effects at different levels on the body.
Electricity Hazards
Depending on the severity, an electric shock will cause voluntary and involuntary muscle contraction. This can cause secondary effects in the human body.
When muscles contract, you may be thrown to the ground or against a wall.
If working from a ladder, an electric shock may cause your body to convulse and fall to the ground.
The secondary injuries can cause:
Electricity Hazards
Electrical Burns occur when electricity (current) flows through the body.
Electricty flowing through the body can cause severe internal and external tissue burns.
One thing to note is that the instantaneous current available in typical outlets can be 100's of amps.
Click on the ranges of amps to the right to read the severity of burns.
Electricity Hazards
Arc BlastsArc Blasts occur when electricity shorts (or flashes) across air from one conductor to another. Basically, current is still flowing even though there is no physical contact between two conductive surfaces. Arc blasts contain large amounts of energy and can result in serious injury or death.
Arc blasts most commonly occur when operating switches. When a qualified person operates a switch, be sure to stand to the side of the panel switches, not directly in front of it. As the switch is operated, look away to reduce chances of being injured. In addition, keep others away from the panel and stay back at least 4 feet.
Only qualified personnel shall operate switches and circuit breakers. For circuit breakers or switch problems, contact your supervisor, do not attempt to operate the switch.
Click on the numbers for additional information pertaining to arc blasts.
Electricity Hazards
Some common causes of arc blasts include the following:
Electricity Hazards
Another hazard of working with electricity is the potential for an explosion to occur. Explosions occur when sparks or arcs ignite flammable gases or vapors. Explosions can cause serious or fatal injuries and extensive property damage.
An explosion would occur under the following circumstances when a flammable atmosphere or substance ignites:
To ensure your safety:
Intrinsically safe apparatus: Apparatus in which all the circuits are intrinsically safe. See UL 913
Intrinsically safe circuit: A circuit in which any spark or thermal effect is incapable of causing ignition of a mixture of flammable or combustible material in air under prescribed test conditions. See UL 913
Apparatus enclosed in a case that is capable of withstanding an explosion of a specified gas or vapor that may occur within it and of preventing the ignition of a specified gas or vapor surrounding the enclosure by sparks, flashes, or explosion of the gas or vapor within and that operates at such an external temperature that a surrounding flammable atmosphere will not be ignited thereby. See NFPA 70
Electricity Hazards
Another hazard to be concerned with is electrical fires. Electricity is one of the most common causes of fires in homes and workplaces.
Electrical fires can be caused by:
If an electrical fire starts, it could easily ignite surrounding flammable materials or chemicals.
Electricity Hazards
Knowing how to extinguish an electrical fire is important. If you encounter an electrical fire, follow the steps below:
Summary
In this lesson you learned about electricity hazards. Let's review the key points from this lesson:Checkpoint
The primary hazards of electricity include:Checkpoint
Which of the following are true of arc blasts:Minimizing Electrical Hazards
Minimizing Electrical Hazards
Working on or Near Electrical Equipment
Electrical equipment and exposed electrical parts shall be de-energized and placed in an electrically safe work condition before working on it.
Process for achieving and verifying an electrically safe work condition:
DO NOT remove lockout/tagout devices from equipment unless authorized.
Minimizing Electrical Hazards
Working On or Near Energized Exposed Live Parts
UNQUALIFIED PERSONNEL SHALL NOT WORK ON OR NEAR ENERGIZED EXPOSED PARTS.
Qualified personnel shall not work on or near energized exposed parts, unless:
Minimizing Electrical Hazards
Electrical Lockout/Tagout
One way to minimize electric hazards is to use the lockout/tagout procedure.
Lockout/tagout is a procedure used to isolate sources of potential energy during repair or maintenance of equipment.
If someone is working on a piece of equipment, lockout/tagout will ensure it is impossible to energize the circuit.
IF a lockout/tagout procedure needs to be performed you must receive specialized training.
Click the images below to learn more.
Minimizing Electrical Hazards
Preventing Electrical Fires
We learned that one hazard of electricity is a fire. To minimize the possibility of a fire, the following should be adhered to:
Minimizing Electrical Hazards
Guarding of Equipment
Electrical equipment can be dangerous so it is important that only qualified personnel have access to live, exposed parts.
Workers need to be protected from live electrical parts if the following rules apply:
Unqualified personnel shall not have access or attempt to work on live electrical parts.
Minimizing Electrical Hazards
Hazardous Areas Must be Identified Using Signs, Postings, and Barriers
Hazards can be minimized by reading and obeying the warning signs.
Remember that entrances to hazardous areas must be posted!
To minimize any hazards - Stay away from energized systems and live, exposed parts.
If you see an area that is cordoned off, do not enter it. The area is cordoned off for your protection and safety.
Minimizing Electrical Hazards
Grounding
By grounding, a low resistance path to the earth is achieved reducing the possibility of injury or death from electric shock. This ensures that unintended parts do not become energized.
NFPA 70E requires grounding of all exposed non-current carrying metal parts which are likely to become energized.
Most electrical equipment is designed with a grounding system.
Minimizing Electrical Hazards
Equipment Grounding
Equipment grounding is an additional ground for enhanced worker protection. It must be furnished by providing another path from the tool or machine through which current can flow to the ground. This ground primarily protects the worker if the tool or machine becomes energized.
Equipment may be grounded by more than one method but, the original ground with the circuit wiring must not be removed or isolated.
You can add supplemental grounds to exposed parts that could become energized during maintenance or set up of experiments. You do not want to use supplemental grounds as a primary means of protection.
Remember - Do not use:
Minimizing Electrical Hazards
Electrical Protection Devices
There are three main types of electrical protective devices:
Fuses and circuit breakers are installed to protect conductors and equipment, and help in minimizing electrical hazards. GFCIs are specifically designed to protect people.
Fuses can only be used once. Circuit breakers can be reset. GFCIs are used in high risk areas and must be tested frequently.
Minimizing Electrical Hazards
Plugs and Receptacles
The following are ways to minimize the hazards when using plugs and receptacles.
Minimizing Electrical Hazards
Electrical and Extension Cords
Electrical and extension cords can be dangerous. You can minimize any hazards by inspecting cords for damage and not using them if they are damaged. Make sure to keep cords clean and free from kinks.
Make sure that you are using the appropriate wire gauge as certain tools have higher ratings than others. In addition, portable equipment and cords need to be approved for the conditions where they are used.
Use permanent wiring rather than extension cords wherever possible. If you must use an extension cord, use the shortest one for the job with a GFCI.
Dry hands thoroughly before plugging cords or equipment. Extension cords are for temporary use. Never use extension cords as permanent wiring. Never connect cords together in wet environments, water could seep into the joint. GFCI are required when using cords in wet areas.
Minimizing Electrical Hazards
Electrical Personal Protective Equipment
Personal Protective Equipment (PPE) is a form of extra protection and is a good way to keep yourself from harm.
PPE is worn to help prevent injury.
Personal protective equipment includes:
NOTES:
Metal jewelry such as watches, earrings, bracelets, rings, and necklaces can easily conduct electricity. Remove all jewelry while working near electricity. Be aware that other personal items such as metal belt buckles, buttons, and certain synthetic fibers also conduct electricity and should be avoided while working near electricity.
Minimizing Electrical Hazards
When to use Personal Protective Equipment
The level and degree of electrical PPE required depends on the level of electrical hazard.
For example, if there is an extreme risk of arc flash, a high degree of PPE will be required (flame retardant suit, hard hat, and insulating gloves).
A lower degree of PPE may be required when checking for voltage on a 120 volt circuit (protective eye glasses, long sleeve shirt, and insulating gloves).
Work-specific procedures for each laboratory/condition or scenario will dictate PPE requirements.
Minimizing Electrical Hazards
When are you required to use PPE?
The degree of the hazard dictates when to wear PPE and the amount of PPE to be worn. The PPE requirements for various hazard levels are stated in NFPA 70E. These requirements shall be strictly adhered to. You should consult your supervisor or safety coordinator to establish when to wear and what PPE must be worn. This shall be done before any electrical work begins and before energizing circuits.
Reminder: there are only 2 situations in which a qualified person may approach energized exposed parts:
Minimizing Electrical Hazards
Hazardous Practices to Avoid
Bad habits and working around electricity can be dangerous or fatal. To minimize electrical hazards, refrain from practicing the following:
Other bad habits to avoid include:
Summary
In this lesson you learned about minimizing electricity hazards. Let's review the key points from this lesson:
Checkpoint
Use of this procedure to "isolate and de-energize" sources of potential energy during repair or maintenance of equipment will minimize electric hazards.Checkpoint
There are three main types of electrical protective devices. Which of the following is specifically designed to protect people?Checkpoint
Personal protective equipment includes which of the following (choose the best answer)?Responding to Electrcial Shock Emergencies
Responding to Electrcial Shock Emergencies
When to call emergency personnel
When you come upon a situation, it is important to know when to call 911 for additional help.
If you come across a person who has been injured, call 911.
Injuries to contact 911 include:
If in doubt call 911!
All other types of injuries should be reported to your supervisor for appropriate medical attention.
Responding to Electrcial Shock Emergencies
Electrical emergencies pose severe hazards not only to the victims, but also to potential rescuers.
If you are presented with an emergency situation, follow these steps
Responding to Electrcial Shock Emergencies
Responding to Electrical Shock Emergencies
After the victim has been de-energized, remember to do the following:
You will also want to collect data for an investigation and to help prevent a reoccurrence of the accident.
Make sure that you report all accidents to your supervisor. Even minor shocks and close calls must be reported.
If it is a minor shock, the person should immediately seek medical attention as cardiac arrest can occur even hours after the shock.
Responding to Electrcial Shock Emergencies
Near Misses
A near miss is an incident that doesn’t usually end up in injury or property damage.
If you witness a near miss or recognize a dangerous situation, you must report it to:
Allowing proper personnel to analyze and resolve a near miss situation can prevent a future injury or death.
Remember-
Safety is your responsibility.
Look out for your safety along with the safety of others.
Summary
In this lesson you learned about what to do in an emergency. Let's review the key points from this lesson: