What does a conductor allow to move through it easily?Electrical current
What are some examples of conductors?Metal, wet skin, and water with small amounts of salt or other minerals are all examples of conductors. Electrical current can easily move through these materials. This means that anyone working with electricity in a damp or wet environment needs to exercise extra caution to prevent electrocution.
What is an insulator?An insulator provides resistance to the movement of electrical current.
What are some examples of insulators?Pure water, plastic, and dry skin are all examples of insulators. They prevent the electrical current from traveling easily through them. Because electric currents will always follow the path of least resistance, these currents will choose any other more conductive material rather than attempt to move through insulators. Other examples of insulators include rubber, wood, cloth, glass, and the earth.
What properties does a conductor have?A conductor is a substance that allows electrical current flow.
Which factor increases the risk of injury if a person is shocked?Sweat creates a wet surface on the skin and makes a person a better conductor, which increases the risk of injury from an electrical shock.
The electrical circuit is accessed through what?Receptacles. In other words, when tools or equipment wires are plugged into a wall socket, those tools and equipment become part of the circuit. When we plug in an electrical device, we are using the current of electrons that is generated at the power plants and placed onto the national electric power grid.
Can people become part of a circuit?People can become part of a circuit. When a person becomes part of an electrical circuit, that person can be shocked.
What can an electric shock result in?An electric shock can result in anything from a slight tingling sensation to immediate cardiac arrest.
The severity of an electric shock depends on what?1. Amount of current flowing through the body.2. Current's path through the body.3. Length of time the body remains in the circuit.4. Current's frequency.
Electrical BurnsElectrical burns are among the most serious burns and require immediate medical attention. They occur when electric current flows through tissues or bone, generating heat, and causing damage. Entrance Wound: Because the skin is an insulator, it transforms electrical energy into heat, which produces burns around the entrance point (dark spot in the center of the wound).Exit Wound: Current flows through the body from the entrance point, until finally exiting where the body is closest to the ground. A foot suffered massive internal injuries, which weren't readily visible, and had to be amputated a few days later.
Arc or Flash BurnsArc or flash burns result from high temperatures caused by an electric arc or explosion near the body. An example of an arc flash is a lightning bolt. The electrical current travels through air. This type of arc flash generates enough heat to melt metal. The same process can happen with any electrical device. In fact, cauterization tools are used to create arc flashes that the surgeon can use to intentionally fuse tissue. When an arc flash is not intended, a burn injury is the result.
Thermal Contact BurnsThermal contact burns are caused when the skin touches hot surfaces of overheated electric conductors, conduits, or other energized equipment. Thermal burns also can be caused when clothing catches on fire, as may occur when an electric arc is produced.
Electrocution means what?Electrocution means to injure or kill with electricity and occurs when a person is exposed to harmful amount of electrical energy.
What job field has the highest risk of electrocution?Construction workers have the highest risk for electrocution
What is an Arc Flash?An arc flash is the sudden release of electrical energy through the air that gives off thermal energy, or heat, and bright, intense light that can cause burns. Temperatures have been recorded as high as 35,000 °F. A lightning bolt is an example of an arc flash.
What is an example of an arc flash in the workplace?A source of an arc flash in a workplace setting is the circuit breaker box. If a circuit is tripped in the breaker box, DO NOT attempt to reset it - rather, immediately contact a supervisor to report that situation. If a switch is flipped to the off position, someone may be working on an electrical device located in that specific circuit, or there may be an electrical short or exposed wire that could potentially create an arc flash. To avoid accidental electrocution, never attempt to open a breaker box: always contact a supervisor.
What can fire be caused by?Fire can be caused by fixed wiring—electrical wires inside the walls of buildings—especially when the wires are old or the outlets are faulty. Fire can also be caused by flexible wiring such as extension cords, appliance cords, or by plugs, receptacles, and switches.
About 3 o'clock this morning, firefighters responded to a building fire. While the fire was limited to one room and there were no injuries, there was about $5,000 worth of damage to structures. It was determined that electrical wiring from the mini-refrigerator to the wall receptacle was the cause of the fire. The mini-refrigerator fire was most likely caused by what type of wiring?The fire was most likely caused by flexible wiring as the refrigerator cord was responsible for the fire.
Some overhead power lines have what that protects power lines from exposure to the elements?Protective covering. However, the covering does not protect workers from electrocution. If you touch a power line, covered or bare, death is probable.
A worker standing on a freshly mopped floor is adjusting products on a metal shelf with which there is a bare wire in contact.The worker makes contact with an energized source because the bare wire is in contact with the metal frame - also a conductor - and the worker is touching it whilst standing on a wet surface.
After a strong storm, a worker does not realize that a power transmission line has fallen on the car and is electrocuted while opening the car door.By opening the door, the worker comes into contact with the metal frame that is in contact with an overhead power line.
A client is undergoing therapy in a whirlpool unit that has been plugged into an extension cord.The whirlpool therapy unit should be plugged directly into a receptacle with a GFCI.
What does OSHA require employers to construct and install to minimize electrocution hazards?1. Lighting found throughout the building2. Appliances such as freezers or refrigerators3. Switches used with generators4. Controls on equipment and machinery in the workplace
OverloadsDo not overload circuits.
Check switches and insulationTools and other equipment must operate properly. Make sure that switches and insulating parts are in good condition.
Three-Prong PlugsNever use a three-prong grounding plug with the third prong broken off. When using tools that require a third-wire ground, use only three-wire extension cords with three-prong grounding plugs and three-hole electrical outlets. Never remove the grounding prong from a plug! You could be shocked or expose someone else to a hazard. If you see a cord without a grounding prong in the plug, remove the cord from service immediately.
CordsRemove cords from receptacles by pulling on the plugs, not the cords.
Extension CordsUse extension cords properly. If an extension cord must be used, choose one with sufficient ampacity for the tool being used. An undersized cord can overheat and cause a drop in voltage and tool power. Make sure the insulation is intact. To reduce the risk of damage to a cord's insulation, use cords with insulation marked "S" (hard service) rather than cords marked "SJ" (junior hard service). Make sure the grounding prong is intact. In damp locations, make sure wires and connectors are waterproof and approved for such locations. Do not create a tripping hazard.
A Ground Fault Circuit Interrupter (GFCI) is designed to do what?1. Protect people from severe and sometimes fatal electrocution by monitoring for electrical leakage on the ground.2. Detect when the current leakage is greater than 5 mA.3. Interrupt the flow of electric current by tripping quickly enough to prevent electrocution from leakage.
In a case where electrical current leakage from the circuit occurs, the GFCI would do what?1. Sense the current leakage2. Trip the circuit3. Cut off the electricity
Will the GFCI protect you from line contact hazards?The GFCI will not protect you from line contact hazards (i.e. a person holding two "hot" wires, a hot and a neutral wire in each hand, or contacting an overhead power line). However, it protects against the most common form of electrical shock hazard, the ground-fault. It also protects against fires, overheating, and destruction of wire insulation.
What does lockout/tagout mean/do?1. Protects workers from injury while working on or near electrical circuits and equipment.2. Locks the device or power source and prevents anyone from turning on the hazardous power sources while someone is performing maintenance or servicing work.3. Requires workers to place a tag on the locked device indicating that it should not be turned on. When using a tag, other energy isolation techniques may be necessary to maintain worker safety.4. Prevents contact with operating equipment parts such as, blades, gears, shafts, etc.5. Prevents the unexpected release of hazardous gases, fluids, or solid matter in areas where workers are present.
Employers should attach tags to identify equipment or circuits being worked on while any worker is exposed to contact with what parts?Live parts
How does a GFCI protect you?It detects if there is any current leakage and cuts of the electrical flow.
Is using a three-prong plug with a missing ground post safe or unsafe?It is unsafe to use a three-prong plug with a missing ground post.
Is placing a plug into a wall receptacle with your hand on the plug safe or unsafe?It is safe to place a plug into a wall receptacle with your hand on the plug, rather than on the cord.
Is it safe or unsafe to pull on a cord to remove plug from a wall receptacle?It is unsafe to remove a plug from a receptacle by placing your hand on the cord. Always place your hand on the plug to remove a cord from the wall receptacle.
When a person is injured or killed after being exposed to a harmful amount of electrical energy it is known as what?Electrocution
A client is undergoing therapy in a whirlpool unit that has been plugged into an extension cord. What is this an example of?Using extension or flexible cords improperly.
A worker standing on a freshly mopped floor is adjusting products on a metal shelf. There is an exposed wire in contact with the shelving. What is this an example of?Contacting energized sources