According to the Electrical Safety Foundation International, there are over 2,000 electrical injuries every year in America. In 2017 there were 136 fatalities caused by electrocution, and 2.6% of all workplace fatalities were as a result of electrical injuries. While those numbers may not seem incredibly high relative to some other things, they're that low for a reason - people who work around electricity follow safety precautions to minimize the damage caused by accidental exposure to high current, arc flashes and electrical fires. Obviously, the training is working well, but until those numbers get down to zero, it could definitely be better. Even a single fatality is clearly too many.
Electricians need to be fully aware of all aspects of safety in and around electricity because of how volatile and sudden the injuries can be. From how to properly ground themselves, to de-powering machines and tools to understanding what safety equipment is necessary when and why, an electrician really needs to be on the ball. Electrical safety is definitely something that comes with knowledge and experience - 16- and 17-year-olds who work with electricity experience electrical accidents at a rate 5.4 times higher than normal. This is knowledge you need to take in and understand, and it really develops over time. If you think you know your electrician safety, then you need to take the quiz!
Which of these risks is associated with electricity?
All of the above
Electricity can be harmful in any number of ways. Direct exposure is a shock risk while the heat generated by electricity can be a fire hazard or, if other dangerous materials are nearby, an explosion risk as well.
What's the first thing you should do if a coworker is being electrocuted?
Pull them free of the power source.
Turn off the power source.
Turning off the power source is the first thing you need to do, if possible, when someone is being electrocuted. You never want to make physical contact with that person with your bare hands, as you'll end up being electrocuted also.
If you're working in a damp space, what do you need to do?
Elevate all electrical outlets and wiring.
Install and use ground fault circuit interrupters.
In any damp space, you'll want to make use of ground fault circuit interrupters. Because the risk of shock is so high in damp conditions, a GFCI will interrupt the circuit before electric shock can occur.
If you're servicing an appliance, what's the first thing you need to do?
Expose the battery or motor.
Test to ensure it's de-powered.
The power to any device or appliance needs to be off before electrical work can be done. if you aren't 100% sure it's off, it should be tested before any work is done. A tester can check wires, the outer box and any exposed wires for a current.
What is the name of the practice that involves locking down an electrical device and labeling it so others know who locked it and why?
Lockout/Tagout, or lock and tag, is a standard procedure of locking down any machine and tagging it at the same time so that anyone else who might approach knows it's shut down and knows why, so they don't turn it back on again.
PPE, or personal protective equipment, is any equipment and gear that protects against health and safety risks in the workplace. Any tradespeople, not just electricians, will have a specific set of PPE that works for their job.
Ladders can be made from a variety of materials, but what material is best for an electrician's ladder?
An aluminum ladder could conduct electricity while a wooden ladder will deteriorate over time and in wet environments. A fiberglass ladder is durable and also will not conduct electricity, making it a solid choice for an electrician.
Which one of these would require that a device is replaced or repaired?
All of the above
If the wires to any device have started to fray or the insulation over the metal wiring is showing signs of cracking and damage that could expose the fire inside, these devices should be replaced or repaired before use. Likewise, a broke plug must be replaced before attempting use.
What kind of jewelry is safe to wear when doing electrical work?
None of the above
Your safest bet for doing any electrical work is to not have anything on that could potentially conduct electricity. Even if an earring would not come in contact with a piece of equipment, electricity can arc and will be attracted to that metal.
Gloves should be made of what two materials when dealing with electricity?
Cotton and polymers
Leather and rubber
A good pair of safety gloves should have an insulating leather interior that does not conduct electricity and have a leather outer layer which offers additional protection as well as some dexterity and warmth.
IPE stands for Insulating Protective Equipment. While PPE covers the things you wear to stay safe, IPE are those things that cover the equipment and wires, like insulating rubber line hoses or rubber blankets.
What should you assume about every electrical device when you first start work?
Every single device should be treated initially as though it were live and energized. With this precaution in mind, you'll greatly reduce the chance of accidental shock by being prepared to deal with a live device.
Why is it a good idea to only work with one hand whenever possible?
Allows for greater accuracy
Easier to work in confined spaces
Reduces shock risk
Working one-handed greatly reduces your risk of a potentially harmful shock. Since electricity follows the easiest path to the ground, it will travel down from one hand. If you get shocked using two hands, it can cross your body and damage organs like your heart more easily.
What do you need to do with a capacitor before working near one?
Because the purpose of a capacitor is to store a charge, that charge will need to be drained before any work can be done. Otherwise, you run the risk of giving yourself a jolt that can be as powerful as touching an exposed wire.
A room that can get very cold has certain risks as it relates to electricity. What's one of them?
The potential risk of electrical equipment in rooms that can get very cold is condensation. Warm, humid air can condense and then warm up again, which creates that moist condensation and increases the risk of damage and shock. Equipment should be wall mounted if possible.
Do you know the minimum amount of clear working space needed in front of an electrical panel?
An electrical panel needs 30 inches of clear space in front of it to allow for any work to be done in a way that minimizes the risk of danger to whoever is working on them by not overcrowding the space.
What do you call work done when you are within arm's length of any energized components?
Energized work is any work done when you're within reaching distance of energized components. This work carries a much higher risk of shocks and electrical arcs but can sometimes be necessary. Precautions must be taken to minimize risk.
There are three shock approach boundaries, do you know what they are?
1st, 2nd, and 3rd
Main, Secondary, Tertiary.
Green, Yellow and Red.
Limited, Restricted and Prohibited
Limited, restricted and prohibited boundaries are part of the electrical code that determines, based on the voltage of a system, what the minimum safe distance from an energized item is and what precautions should be taken to cross that boundary.
What do you call the minimum distance from a live, energized item that an unqualified person is allowed to safely stand
Limited Approach Boundary
The limited approach boundary is the shock protection boundary that unqualified personnel should not cross unless accompanied by a qualified individual. The area beyond the boundary should be treated as though it were live.
To provide an alternate path for electricity to get to the ground
Grounding creates a pathway for electricity to follow to literally get to the ground, which is naturally where electricity will travel. Since electricity will follow the simplest path to the ground, using a ground wire gives it a simpler path than going through a human.
Can you name the correct classification of an electrical fire?
Electrical fires are classified as Class E fires. In the event of an electrical fire, the main power should be cut off if possible and dry or chemical agents should be used to fight the fire rather than water or foam, which could conduct electricity.
It's never a good idea to store combustible liquids near electrical panels. Because of the amount of heat that can be generated by electricity when there is some kind of short or if an electrical fire starts, the fire and explosion risk is too high.
The amount of electricity that you can feel in your skin
The current at which your muscles contract and you can't let go
Somewhere between 6 and 30 milliamperes, depending on the person, you'll reach the "let go" threshold where muscle contractions actually cause you to grip the source of electricity and you are unable to let go, prolonging the exposure and injury.
The current that will physically knock you backward
A current as low as 5 milliamperes will result n a shock and as little as 30 can cause noticeable pain. The human body is pretty resilient and can handle a lot, but 10,000 and above can cause severe damage including death. Most circuits in a home provide over 20,000.
An arc flash can occur in any electrical device and poses a number of safety risks. When the radiant energy explodes outward it can damage hearing as well as vision, and the superheated gas it produces can cause burns.
There are 4 categories of PPE requirements for dealing with arc flash. Each category details the proper protective equipment needed based on the arc rating for what's being worked on. Each level increases the safety equipment needed to prevent injury from arc flash.
How many volts must a portable light used in a wet environment operate at?
15 or more
12 or less
Any sort of portable lighting you would plug in outside must operate on 12 V or less. it should also be plugged into a ground fault circuit interrupter to prevent a potential shock if the dampness affects it.
An extension cord needs to be inspected each and every day before use to look for any frayed wires or damaged insulation. Extension cords are never to be used permanently and should be unplugged once the task is done.
There are two basic types of electricity. The first is static, which is the buildup of a charge on the surface of an object. The second is current or dynamic electricity, which is the flow of a charge across a conductor, or what you might simply refer to as current.
What do you call an excess of current that can lead to fire risk or failed insulation?
When a larger than intended current passes through a system, it's called overcurrent and it can present a serious risk. Over time, even a small overcurrent can damage insulation and lead to fires and shock risk.
What kind of tape can be used to repair an extension cord with split insulation?
None of the above
Extension cords are not to be repaired or patched with tape or anything else if the insulation is damaged or if wires are frayed. A damaged extension cord is no longer safe for use and should be destroyed.
What material do you want to have on your feet when dealing with electricity?
Rubber is one of the best choices for insulating yourself as it will not conduct electricity under normal circumstances. When you wear rubber-soled boots, you are insulated against a current running through your body to the ground.