Electric Burns in the Workplace
Electric burns are an often overlooked hazard in the workplace, but they can cause serious injuries resulting in permanent damage. Safeguard your dream by educating yourself and your employees on common injuries caused by electric burns, so you know the right steps to take to prevent them from happening.
When dealing with electricity, the most common shock-related, nonfatal injury is a burn. Electricity can cause three types of burns:
Electrical burns are injuries that may happen when an electric current (electricity) goes near or passes through your body. If you touch electric currents, parts of your body may be burned. The current may enter your body at one point and exit at another, causing damage wherever it passes inside your body. You also may get electrical burns even if the current does not go through your body. If you are near enough, electricity may jump from an electrical source to you. This creates an arc or flash with enough heat to burn your clothing or body. The current causes the most damage where the electricity enters and exits your body. Your muscles, tendons, blood vessels, nerves, and bones also may get damaged.
Electrical burns cause tissue damage and are the result of heat generated by the flow of electric current through the body. When you are burned, your tissue gets damaged and begins to die. The heat from the burn may damage your bones, and swelling may cause damage to nearby organs. Damaged blood vessels may prevent your organs from getting enough blood. When your muscles are damaged, they may release toxins (dangerous chemicals) into your body. Toxins may damage nearby tissue and organs.
High temperatures near the body produced by an electric arc or explosion cause arc-flash burns. An arc-flash is an unexpected, sudden release of heat and light energy produced by electricity traveling through air, usually caused by accidental contact between live conductors. The air and gases surrounding the arc are instantly heated, and the conductors are vaporized producing a pressure wave called an arc blast. In other words:
An arc-flash is the extremely high-temperature discharge produced by an electrical fault in air, while arc-blast is a high-pressure sound wave caused by a sudden arc fault. Primary hazards associated with an arc-flash and arc-blast include the following.
- The intense light generated by the arc-flash emits dangerous ultraviolet frequencies, which may cause temporary or permanent blindness unless proper protection is provided. The sound energy from blasts and pressure waves can exceed the sound of an airplane taking off, easily rupturing eardrums and causing permanent hearing loss.
- Arcing gives off thermal radiation (heat) and intense light, which can cause burns. Several factors affect the degree of injury, including skin color, area of skin exposed, and type of clothing worn. Proper clothing, work distances, and over current protection can reduce the risk of such a burn.
- A high-voltage arc can produce a considerable pressure wave blast (explosion) that can cause serious ear damage and memory loss due to concussion. Sometimes the pressure wave throws the victim away from the arc-blast. While this may reduce further exposure to the thermal energy, serious physical injury may result. The pressure wave can propel large objects over great distances. In some cases, the pressure wave has enough force to snap off the heads of steel bolts and knock over walls.
- A high-voltage arc can also cause many of the copper and aluminum components in electrical equipment to melt. These droplets of molten metal can be blasted great distances by the pressure wave. Although these droplets harden rapidly, they can still be hot enough to cause serious burns or cause ordinary clothing to catch fire.
Thermal contact burns occur when skin comes in contact with overheated electric equipment, or when clothing is ignited in an electrical incident. Thermal burns may result if an explosion occurs when electricity ignites an explosive mixture of material in the air. This ignition can result from the buildup of combustible vapors, gases, or dusts. Ignition can also be caused by overheated conductors or equipment, or by normal arcing at switch contacts or in circuit breakers.
The severity and causes of electrical hazards are varied, but the best protection is to de-energize equipment before working on it. No one has ever been killed, injured, or burned from an arc-flash/blast while working on de-energized equipment.