How Does Electricity Kill?
Most of us have seen cartoon depictions of electrocution: people or animals touch a socket and shriek as all their limbs extend, their eyes bug out, and their hair stands on end. While these comic illustrations are used for humor, they also hint at the dangers of coming into contact with electricity. But, of course, real electrical injuries are anything but humorous.
In our lives, we have probably experienced small electric shocks, usually from static electricity but sometimes from batteries. Some people even feel it necessary to “test” 9-Volt batteries by sticking the positive and negative terminals on their tongues to feel the tingle of the charge transferring through their saliva. While these are relatively small shocks, they can still sometimes hurt a bit. These experiences give us some sense of the danger we are dealing with and the unique characteristics of electrical hazards.
The Damage Electric Currents Can Cause
Everybody has seen signs that say “Danger: High Voltage” on a fence around a power substation or on other utility equipment. Many people are also familiar with electric chairs, a thankfully bygone form of execution. These extremes can sometimes make us overlook electrical dangers that may be right beside us daily: wall outlets, appliances, junction boxes, power cords on tools and lights, electrical panels, hairdryers, and so on. High voltage lines clearly present a danger, but if something is not right, everyday encounters with electricity can also kill or maim.
What is it that makes electricity so dangerous? It has to do with how electric current works. To explain it simply, you can analogize electric current to water current as electrons move from one place to another. (For this analogy, you can think of voltage as the amount of water pushing the flow.) That flow, measured in “amperes” and called “amperage,” is usually over something that conducts electricity well, such as a copper wire. So long as nothing impedes that flow, electrons can keep flowing from one point to another to provide power to an end device, such as a toaster. The toaster then converts that energy into heat to toast your bread.
If something dams up a stream and prevents water flow, it can result in a build-up of water that can cause an overflow or flood. Similarly, if the flow of electrons is impeded by something that resists the flow, the electrons will output energy in the form of heat at the point of resistance. This is why the toaster can produce heat from electricity to cook your bread.
But we only sometimes want to produce heat; heat is often a byproduct or waste of the energy we want to use. Your computer, for example, will feel warm after a period of use, but it is not meant to be a heater. As current from your wall socket or the internal battery runs through your computer, some of its components will provide some resistance to the flow. Too much heat can ruin delicate computer components, which is why you cannot block certain parts of the computer. The heat needs to be dissipated, or your computer will, as they say, “fry.”
Incidentally, water is also a good conductor of electricity. Accordingly, using electrical appliances near bathtubs, sinks, or pools is dangerous. Spilling water on electrical devices or flooding of your appliances can create hazardous situations and destroy electronic devices – including electric cars, computers, phones, and tablets.
Well, just as with a computer, if current comes in contact with your body, your body conducts electricity. If dry, your skin offers pretty good resistance and protects you; you will quickly let go of a hot wire. But if you have wet hands or the current is high, the current can breach your skin and enter your body. Different tissues in your body have different levels of resistance; when current reaches those tissues, that resistance will create enough heat to burn. Your internal organs can burn and get damaged, which can sometimes cause death. This is why, even if a person survives an electric shock injury, it can result in long-term and delayed effects on health from damaged internal organs.
But burning is not the only risk. The electrons flowing through your body interfere with your body’s own electrical charges that transmit neural signals. These neural signals tell your muscles to move – including the most important muscle: your heart. Muscles will seize up if someone has current running through them, and a person may not be able, physically, to move away from the energized source because they cannot control their muscles. If the current reaches the heart, it will cause the heart to fibrillate. This disrupts the regular beating of the heart and can lead to cardiac arrest almost immediately.
It Does Not Take a Lot of Current to Cause Serious Injury
Although this is a somewhat simplified explanation, it is easy to see how dangerous it can be to come into contact with an energized line. The higher the current running through a person’s body, the more damaging it can be. According to OSHA charts, 50 milliamps (mA, or 1/1000th of an ampere) of current is likely to cause serious injury, and ten amps is likely to be lethal. (To put this in perspective, the standard wall outlet is rated for 15 amps, which is why most outlets today have ground fault interrupters, or GFI, which saves lives by shutting off power if the returning current is different than the output current.) However, the lethality of any electric shock event will also depend on the course the current takes through the body. A small amount of current that goes directly through the heart can lead to death, and a high amount of current that takes another path, say through the skin to the ground, may only result in severe burns.
The generated electricity is ever-present in our world, and much work is invested in supplying the electricity that makes modern life possible. This means power lines everywhere . . . and danger everywhere. Safeguard Equipment was established precisely because its founders recognized the unique risks that energized lines present, not only for those who have to work on power lines but for everyone who regularly works with or confronts electrical dangers. It is to keep these men and women safe from the injuries described here that Safeguard Equipment designs and manufactures Personal Voltage and Current Detectors (PVCDs), which can detect energized fields and give warning to workers of this unseen danger.
Safeguard Equipment’s newest product, the COMPASS Pro emergency response solution, combines the utilities of its standard PVCD but also adds fall, arc flash, and man-down detection capabilities. These detection powers are combined with a phone-based app that provides communication connectivity for rapid emergency response. This unique product not only prevents electrical injuries but also ensures that, should a worker experience any injury event, emergency medical help can be summoned on-scene immediately.