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

Electrical Work Practices are Regulated

The two governing agencies that regulate electrical work include:

1. Occupational Safety and Health Administration (OSHA)
2. National Fire Protection Association (NFPA 70E)

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.

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:

• Know the proper use of special precautionary techniques
• Know the proper use of personal protective equipment (PPE)
• Undergo On The Job training for your specific duties
• Demonstrate the ability to perform duties safely
• Know emergency procedures related to your work area

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:

• Be able to recognize electrical equipment
• Recognize lockout/tagout devices and know what to do when they are encountered

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:

• Low Voltage (0-50 Volts)
• Medium Voltage (51-600 Volts)
• High Voltage (601 Volts and higher)

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).

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.

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:

• In order for electricity (current) to flow it must have a completed circuit.
• When the human body, tools, or unintentional items become part of a circuit, electricity becomes extremely dangerous.

• List some hazards associated with electricity, and
• Define the different hazards associated with electricity

• Electric Shock
• Electric Burns
• Arc Blast

• Explosions
• Electrical Fires
• Secondary Injuries

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:

• Path of current
×

The points where electricity enters and exits the body will determine which parts of the body are affected by shock. If electricity flows through the center of the body, passing through the heart, the results are often fatal. If electricity flows through an arm or leg, the damage is less severe.
• Amount of current
×

The more current that flows through the body, the more severe the injury will be.
• Duration of the shock
×

The longer the current flows through the body, the more severe the injury will be.

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.

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:

• Bruises
• Broken bones
• Cuts
• Head injury
• Internal organ or tissue damage

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.

Some common causes of arc blasts include the following:

• Using a multimeter with wrong ratings.
• Using a voltmeter not rated for the circuit voltage.
• Working with tools on an energized circuit.
• Short circuit between bus bars or cables carrying heavy current and voltage.
• Pulling fuses in energized circuits.

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:

• An electric spark or arc from electrical equipment
• A static spark from a person touching a conductive material

To ensure your safety:

• Use proper grounds. Use electrical equipment that is properly grounded. Supervisors or qualified personnel must approve grounding.
• When working in or near flammable atmospheres or chemicals, use Intrinsically Safe
  ×

  
  

  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

  or Explosion Proof
  ×

  
  

  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

  electrical apparatus, including switches, outlets, motors, etc.
• Consult an electrical safety professional to ensure that the setup is safe before working in a flammable atmosphere or near flammable chemicals.

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:

• Failure of electrical equipment,
• Short circuits,
• Static electricty,
• Improper wiring,
• Improper grounding, or
• Lightning.

If an electrical fire starts, it could easily ignite surrounding flammable materials or chemicals.

Knowing how to extinguish an electrical fire is important. If you encounter an electrical fire, follow the steps below:

1. Ensure your personal safety.
2. Call 911 immediately, if the fire alarm has not sounded, pull a manual fire alarm pull station and warn others in the area.
3. If it can be done safely, shut off the power to the burning equipment or area.
4. Help injured personnel if safe to do so (DON'T BECOME A VICTIM YOURSELF).
5. If small fire persists, extinguish with appropriate fire extinguisher - Class ABC, CO₂, or Halon. Never use water or foam extinguishers on electrical fires.

• Describe ways to prevent and minimize hazards.
• Describe what to do in an emergency.
• Identify when to call emergency personnel.

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:

1. You are checking to determine if parts are de-energized or troubleshooting a circuit (using appropriate PPE, metering equipment, and techniques).
2. It is impossible to make the part inaccessible or put the part in an electrically safe work condition, in which case you shall still maintain a safe distance from the exposed energized parts and use appropriate PPE and safe work techniques.

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:

• Use proper electrical equipment installed by certified electricians,
• Follow operating instructions of electrical equipment,
• Use proper electrical devices in flammable atmospheres,
• Keep flammable materials away from electrical circuits and experiments because electrical fires can start secondary fires, and
• Use ‘inherently safe’ or ‘explosion proof’ electrical equipment in flammable atmospheres.

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:

• Voltage must be guarded by an approved means of enclosure.
• Enclosures must be marked with highly visible warning signs.
• Electrical equipment is only accessible to qualified personnel.

Unqualified personnel shall not have access or attempt to work on live electrical parts.

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.

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:

• Equipment with damaged grounding connectors or
• Adapters that interrupt the grounding connection.

Plugs and Receptacles

The following are ways to minimize the hazards when using plugs and receptacles.

• Use plugs that are appropriate for equipment and receptacle.
• Inspect plugs for damage.
• Use ground plug if required.
• Do not remove plug by pulling on cord.
• Never break ground prong off of 3-wire male plug to fit into 2-wire female plug.
• Never overload a circuit with too many plugs.

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.

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:

• Rubber gloves, sleeves,
• Eye protection,
• Plastic hard hats,
• Non-flammable clothing,
• Electrically insulated boots, and
• Insulated tools

NOTES:

1. PPE SHALL NOT be used in place of de-energizing equipment or circuits for maintenance…even if you are a qualified worker.
2. ONLY a qualified person should even need to wear PPE….unqualified workers shall never approach exposed energized parts.

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.

Hazardous Practices to Avoid

Bad habits and working around electricity can be dangerous or fatal. To minimize electrical hazards, refrain from practicing the following:

• Poor housekeeping
• Frayed and damaged wires and cords
• Exposed live connections and parts
• Blocked electrical equipment
• Not using proper signage or postings to indicate potential hazards

• Identify when to call emergency personnel
• Describe what to do in an electrical shock emergency

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:

• Unconscious victim,
• Electrical shock has occurred
• Significant trauma,
• Altered mental state-confusion, slowed or slurred speech,
• Large lacerations,
• Excessive bleeding, and
• Large burned areas.

If in doubt call 911!

All other types of injuries should be reported to your supervisor for appropriate medical attention.

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

1. Do not enter the scene if it is not safe for you to do so. BE AWARE OF HAZARDOUS SURROUNDINGS AS YOU APPROACH THE VICTIM.
2. If the person is being shocked, DO NOT touch the victim. This will make you part of the circuit, and you will be shocked.
3. Do not touch the equipment as it might be energized and this will make you part of the circuit, and you will be shocked.
4. If possible and able to do safely, immediately shut off the power at circuit breaker or other type of power disconnect.
5. If you have to move the victim, try to free the person with a non conductive object– wooden broom handle, leather belt, unpainted board, plastic pipe, etc.

Responding to Electrical Shock Emergencies

After the victim has been de-energized, remember to do the following:

1. Call 911 (or ask someone else to call)
2. Provide First Aid and CPR (if you are certified)
3. Secure the area

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.

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:

• Your supervisor,
• The departmental safety coordinator, or
• FSU Department of Environmental Health and Safety

Allowing proper personnel to analyze and resolve a near miss situation can prevent a future injury or death.