Electrical & Natural Gas Safety World VideoTeacher’s GuideThe Electrical & Natural Gas Safety World video explains electric and gas science concepts and how to use these energy sources safely in daily life. The content addresses many state and national curriculum standards for grades 3-7, including physical science (electricity in circuits), earth science, and health and safety. The video includes seven 3-minute episodes, each on a different safety topic. This presentation guide includes learning objectives, key concepts, discussion questions, and follow-up activities to reinforce the core messages of each episode. You may wish to introduce these basic energy concepts to your class before showing the video:Energy is the ability to change or move matter. Without energy there would be no motion, no light, and no heat, and life would not exist. The sources of energy we rely on are very important in our everyday lives. Appliances like refrigerators, ovens, heaters, water heaters, clothes dryers, TVs, computers, and air conditioners all need energy to work. Explore these concepts through the following classroom activity:
For most classrooms, electricity and natural gas will be the most commonly used forms of energy. It is important to understand the following principles about these energy sources so we can use them safely:
Episode 1: ELECTRICITY BASICSObjective: To make students aware of where electricity comes from, its properties, how it gets to our homes and schools, and the dangers associated with it. Key Concepts:
Electricity is generated at power plants where various natural resources can be used to turn turbines. The turbines turn electromagnets that are surrounded by heavy coils of copper wire. The moving magnets cause the electrons in the copper wire to move from atom to atom, generating electricity. (Atoms are tiny particles that make up everything around us, and electrons are even tinier particles that orbit the center of an atom. When electrons move from atom to atom through wires, electricity is created.) Electricity travels over power lines and wires in a closed loop called a circuit. Electricity will leave a circuit if something or someone provides it with a path to the ground. Safety hazards occur anywhere a person could come into contact with electrical lines or equipment. This includes power lines, transformer boxes, substations, and electrical appliances. As long as a person is touching the ground (or something in contact with the ground), electricity has the potential to travel through him or her, causing shock, burns, or even death. Discussion:
Going Further: Students may be under the impression that they can move faster than electricity in order to avoid electrical shock. Explain that electricity travels extremely fast (186,000 miles per second). If they traveled that fast, they could travel around the world eight times in the time it takes to turn on a light switch. Take students outside the school building and locate lines, transformers, and the entrance of electrical lines into buildings. What other equipment can they see? (Probably the electric meter.) What is it used for? (To measure how much electricity is used in the building.) Ask students to make a map of power lines or other electrical equipment near the school (or in their neighborhood at home) that people should stay away from. Episode 2: CONDUCTORS & INSULATORSObjective: To teach students the dangers of contacting an electrical circuit, and to teach them to recognize materials that conduct and insulate from electricity. Key Concepts: Insulators are materials that do not allow electricity to flow through them easily. Special rubber, plastic, and glass are used as insulators. Utility workers wear insulating materials to protect them from electrical shock, because contacting a power line is dangerous. Safety note: Explain to students that even though some power lines—such as those that run from power poles to buildings—may appear insulated, the coating around them is designed to protect the lines from weather, not to protect people from shock. Insulating materials keep electricity inside appliance cords. Rubber or plastic insulation around the cords keeps the electricity in the wires and prevents you from getting a shock. Cords with worn or frayed insulation, or cords that have been taped, are dangerous, and touching one can give you a major shock, as there is no protection from the electricity in the circuit. Conductors are materials that allow electricity to flow through them easily. Water and metal are good conductors. That’s why metal wires are used for power lines or appliance power cords. Your body is also a good conductor. So if you touch a wire or electrical appliance that is energized (containing live electricity), the electricity can travel through your body to the ground and hurt or kill you. If you overload an electrical outlet by plugging in too many things, you draw more electricity through the wiring in the walls than the circuit can handle. The insulation around these wires could melt, causing a shock and fire hazard. Discussion:
Going Further: Inspect the appliance cords in your classroom to make sure the insulation is intact. Also check outlets to make sure they are not overloaded. If you find an overloaded outlet, transfer some of the plugs to another outlet. Ask students to check the appliance cords and plugs in their homes with an adult. (Remind them to turn them off and unplug them first.) If the insulation is cracked or frayed, they should decide with their family whether they should replace the cord or throw the item away. Episode 3: OUTDOOR ELECTRICAL SAFETYObjective: To teach students to never contact overhead or underground power lines, and to stay away from substations and surrounding fences. Key Concepts: The electricity in power lines is at such high voltage that it can use almost anything, even a kite string, as a path to the ground! If you are holding that string, electricity will travel through you and you will be shocked. So always fly kites far away from power lines. Also keep metallic balloons indoors so they cannot fly into power lines and create a shock hazard. Likewise, always climb trees far away from power lines. If you touch a power line—even if it looks insulated—while climbing a tree or standing on a ladder or a roof, you could be seriously hurt or even killed. Always stay at least 10 feet away from all overhead power lines. This means keeping your body, and any tools or equipment that you are holding, at least 10 feet away from lines of any kind. Pad-mounted transformers (devices used to increase or decrease electricity’s voltage) are found in many neighborhoods and should never be played on. Remind students to report any open/unlocked ones to an adult as soon as possible. Electricity in a substation is very high voltage. Never climb a substation fence or go inside a substation. Ask an adult to call 811 a few days before doing any digging projects. This number connects to the one- call service, which will arrange for local utilities to come and mark any nearby underground electric lines so you can dig safely. Discussion:
Going Further: Divide the class into groups. Give the groups five minutes to make a list of common outdoor electrical hazards. Share the lists. The group with the most hazards wins! Ask students: If metal conducts electricity, why doesn’t electricity travel down metal utility poles? Episode 4: INDOOR ELECTRICAL SAFETYObjective: To help students recognize hazardous situations involving electricity indoors, such as mixing water or metal with electricity, damaging power cords, or overloading outlets. Key Concepts: Do not leave electrical appliances on or use them near water, because water conducts electricity. Do not run appliance cords under rugs. They could get damaged by being stepped on. Do not overload outlets. Too many electrical appliances on one outlet can heat up the wiring in the walls, melt the insulation on the wires, and cause a fire. Discussion:
Going Further: Ask students to locate GFCIs in your classroom or school. What conclusions can they draw about where GFCIs are placed? (GFCIs are used outdoors and in kitchens and bathrooms because the greatest risk of electrical shock occurs near water.) Divide the class into groups. Give the groups five minutes to make a list of common electrical safety mistakes they could find in their homes or in the classroom. Share the lists. The group with the most mistakes wins! Now that students know a little about electrical safety, ask them to be on the lookout for examples of people doing unsafe things around electricity in movies or on television. Did the person get an electric shock? Encourage students to write up their examples and/or do an oral presentation. Have them include what the character did wrong, and what could happen if a real person were to do the same thing. Episode 5: FALLEN POWER LINESObjective: To teach students what to do if a power line falls on their car or on the road. Key Concepts: Stay in the car until utility workers come to tell you it’s okay to get out of the car. (Not all rescue workers are trained to deal with energized power lines, so only utility workers can tell you when it’s safe.) Anyone who touches the car and the ground at the same time could be hurt or killed, so if passersby approach the car, warn them to stay far away. In case of fire, you will need to get out of the car. To do so, jump out as far from the car as you can, and don’t touch any part of the car or ground at the same time. Land with your feet together, and shuffle 20 yards away from the car, keeping both feet on the ground at all times. If you see a fallen power line but you are not trapped in a car, stay far away from the line. Always assume that a downed power line is live, and that the ground around it could be charged with electricity. Stay at least 20 yards away from any downed power lines. Even if the line is not sparking or humming, it could be carrying electricity. Don’t touch the line or anything it is touching, like a tree or fence. Call 911 to report any fallen lines. Discussion:
Going Further: Ask students to practice the emergency exit procedure for leaving a car with a power line on it in case of fire. First have them practice jumping off their chairs with feet together as far out as they can. Then have them practice the 20-yard shuffle outside in small groups. They will need a string or yardstick with which to measure a yard, and then they can map out how far 20 yards is. Ask them to predict how many shuffle steps it will take them to go that distance, and then have them do it to see if they were right. Ask students to create a wallet card warning drivers about the dangers of fallen power lines. Be sure they include how to stay safe and when/how to safely exit the vehicle. Have them give this to a parent to keep in their wallet. Episode 6: NATURAL GAS BASICSObjective: To teach students about the origins of natural gas, how gas gets to us, and basic safety practices around gas appliances. Key Concepts: Methane is a hydrocarbon gas that is the key ingredient in natural gas. Natural gas, found deep in the earth, is the product of decayed plants and animals. Mercaptan is a chemical with the smell of rotten eggs. It is added to natural gas so people will know if gas is leaking. If you notice this smell, go to a safe location and call your gas utility. Natural gas is pumped up through a well and sent through many miles of large pipes to neighborhoods. Smaller pipes carry it into homes, schools, and businesses where it is used to run various appliances such as heaters, dryers, water heaters, and stoves. A pilot light is the small blue flame of some gas appliances that is always burning. You should never store flammable objects or liquids near natural gas appliances. The pilot light could set them on fire. Discussion:
Going Further: Make a bumper sticker about natural gas safety. Episode 7: GAS PIPELINE SAFETYObjective: To teach students the importance of calling 811 before digging, and how to recognize and respond to an indoor or outdoor natural gas leak. Key Concepts: The signs of a gas pipeline leak include a smell of rotten eggs, a hissing or roaring sound, dirt being blown into the air, continual bubbling in water, and grass or plants dead or dying for no apparent reason. If you notice any of these signs, go far away from the area and call 911. If you smell gas in your home, leave and take everyone with you, far away from the area. Don’t use a match, a light switch, or anything else that uses electricity (such as a cell phone or a flashlight) until you are far away. Even the tiny spark of the electrical connection of a cell phone could ignite the gas and cause an explosion. Report the odor to your gas utility. Discussion:
Going Further: Have students conduct a natural gas safety inspection at home. Have them report back what natural gas hazards, if any, they found, and whether/how their family fixed the hazard. Ask students to make a poster to teach people in your community about 811.
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