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NEW! At what depth are residential power lines normally buried?
Answer: Underground power lines in the Dominion service area are buried at depths specified by the National Electrical Safety Code. In general, buried power lines carrying up to 600 volts must be buried at least 24 inches deep, and lines carrying between 601 and 50,000 volts must be at least 30 inches deep, although there are variations on this rule. Landscaping or excavation work in the area can change ground conditions after a power line has been installed and alter its depth. If your family is considering a digging project, always call Miss Utility at 811 to have utilities marked before digging, to allow time for all the utilities to be marked, and to obtain a positive response from Miss Utility.
Is it possible to have an underground power line? How much does an underground power line cost?
Answer: Yes, underground power lines are indeed possible, and are in place all over the country. But putting power lines underground is very expensive. The cost varies according to the type of the line and the geographic location, so I can't provide an exact dollar amount.
How can lightning kill you?
Answer: A lightning strike can carry up to 100 million electrical volts. That's as much electricity as is contained in about 8 million car batteries. A shock of this size can disrupt the body's electrical signals, and stop the heart and brain. For tips on how to stay safe in a lightning storm, check out our site's lightning safety section here: http://www.e-smartonline.net/dom/66400_get_smart/elec_safety-smart/66431_case_of_emergency/lightning.html
Someone told us we could get electrocuted playing on a green power box. Is that true?
Answer: Those green power boxes are called transformers, and their function is to reduce the high voltage of the electricity that travels from power plants along distribution wires so that it can then travel safely along service wires to homes and businesses. Transformers contain equipment that is very dangerous to touch. That's why they have warning signs on them. You could get electrocuted by touching the equipment inside them. This is why you should tell an adult if you ever see one that is damaged or unlocked. As a rule, it's much safer to play far away from them.
Is there a law or regulation as to how high a Dominion power line must be above the ground?
Answer: There are some strict national guidelines stating required heights for overhead power lines above streets, sidewalks, alleys, roads, properties, and driveways. The National Electrical Code (NEC) is the organization that determines acceptable clearances for power lines to keep people from contacting them.
How does natural gas form?
Answer: Natural gas is formed very slowly, deep inside the earth. Over millions of years tiny plants and animals that have died and decayed are buried by mud, sand, and silt, and the forces of heat and pressure inside the earth turn them into natural gas. Certain types of rock formations underground allow the natural gas to form and collect.
Why does metal electrocute you?
Answer: Metal itself cannot electrocute you. However, metal is a good conductor of electricity, which means it allows electricity to flow easily through it. Electricity is a form of energy carried by moving electrons, which are particles that orbit the center of an atom. The electrons in the atoms of metals are only loosely attached, so electricity can travel through them easily. That's why, in order to protect yourself from electric shock, it's so important to never put a metal fork in a toaster, to stay away from metal fences and poles during a lightning storm, and to keep metal ladders away from power lines.
Do natural gas pipes have to be electrically grounded?
Answer: Yes, natural gas pipes do have to be grounded to protect them from stray electrical currents. Damaging electrical currents could come from buried or shorted electrical wires, static electricity, or even nearby lightning strikes. Any of these sources of electricity could create a spark that could damage a metallic pipe and potentially ignite the natural gas it carries.
I was putting raw chicken into a hot frying pan with one hand on the edge of the sink and I got a shock. Is this something to worry about (more than don’t try it again)?
Answer: There are several possible explanations for your shock. One is that you were actually “shocked” by a splatter of hot oil jumping from the pan as you put in the chicken. The body would respond in the same way to this as it would an electric shock, by jerking away. Another possibility is that if you live in an older home, you might have become electricity’s easiest path to the ground, due to your contact with the sink. For an explanation about this, read my earlier response to Dixie who asked a similar question about getting shocked by touching the stove and sink simultaneously. A third possibility is that if your range is electric, it might not be grounded properly. I’d advise your family to have an electrician come and check the circuit to the stove as a precaution, because if the grounding is bad, then operating the stove could be an electrical hazard.
Why is natural gas called “natural” gas?
Answer: Natural gas is called “natural” because when this type of gas was first discovered, it was a naturally occurring gas substance originating from the earth, and it could be used directly from the ground in its natural state without any processing. Today, gas utilities process natural gas by removing water, sand, and other compounds so that when the gas is delivered to your home it will burn as cleanly and efficiently as possible. And in its natural state gas has no odor, so that’s why companies like Dominion add a harmless but stinky chemical to it; the odor helps people smell a leak that otherwise, in the gas’s natural state, doesn’t smell.