Electricity powers homes and countless devices. While a common household voltage of 120 volts might seem relatively low, it can indeed be lethal under certain circumstances. The outcome of an electrical shock depends on several factors, not just voltage.
Understanding Electrical Danger
The danger of an electrical shock is determined by the amount of current (amperes) flowing through the body. While voltage provides the “push,” current causes harm. The relationship between voltage, current, and the body’s resistance dictates how much current will flow.
Human body resistance varies, playing a role in shock severity. For instance, dry skin offers high resistance, which limits current flow. However, wet skin drastically reduces resistance, allowing a much higher and potentially lethal current to pass through the body at the same voltage.
Beyond current and resistance, the path electricity takes through the body and the duration of contact also influence injury severity. If the current pathway includes vital organs like the heart or lungs, the risk of severe damage or fatality increases significantly. Prolonged contact, even with low voltages, can lead to serious injury or death.
How Electricity Affects the Body
When electrical current passes through the human body, it can disrupt normal physiological functions in several ways. One dangerous effect is interference with the heart’s electrical rhythm, potentially leading to cardiac arrest. Current can also affect the nervous system, which controls breathing, causing respiratory arrest or other neurological damage. Nerve tissue offers little resistance to electrical current, making it susceptible to damage.
Another significant type of injury from electrical shock is burns. These can range from external burns at the entry and exit points of the current to severe internal burns as tissues heat up due to the flow of electricity. The heat generated can damage deep tissues and organs, often without visible external signs. Electric shock can also cause involuntary muscle contractions, strong enough to prevent a person from letting go of the electrical source, prolonging contact. These contractions can also lead to falls or bone fractures.
Real-World 120-Volt Scenarios
Household environments, typically powered by 120 volts, present opportunities for electrical incidents. For example, touching a faulty appliance with wet hands can significantly increase the risk of shock because water acts as a conductor, lowering the body’s resistance and allowing current to flow more easily. Similarly, using damaged electrical cords with frayed insulation or exposed wires poses a direct electrocution hazard, as it removes the protective barrier against live current.
Exposed wiring, from damaged appliances, extension cords, or within the home, can lead to direct contact with live current, resulting in severe shocks, burns, or electrocution. Overloaded electrical outlets can also create dangerous conditions, increasing the risk of overheating or short circuits, which can lead to fires or shocks. Even seemingly innocuous actions, like plugging in a device while standing in water, can facilitate a dangerous electrical pathway.
Responding to Electrical Shock
In an electrical shock event, immediate action is important. The first step is to ensure your own safety by never touching a person still in contact with the electrical source. The current could pass through the victim to you, causing a second injury. The safest immediate action is to turn off the power source at the main circuit breaker or unplug the device if it is safe to do so.
If the power cannot be immediately cut, use a dry, non-conductive object, such as a wooden broom handle, plastic, or cardboard, to separate the person from the electrical source. Once the person is no longer in contact with the electricity, call emergency services immediately. While waiting for professional help, check the person for breathing and pulse. If trained, begin cardiopulmonary resuscitation (CPR) if the person is not breathing or has no pulse. Any visible burns should be cooled with water and covered with a clean cloth.
Preventing Electrical Incidents
Preventing electrical incidents in the home involves vigilance and safety guidelines. Always inspect electrical cords and appliances for damage like fraying or exposed wires, and replace them immediately. Never use damaged cords or appliances. Keeping electrical devices away from water, especially in bathrooms and kitchens, is also a preventative measure, as water increases the risk of electrocution.
Installing ground-fault circuit interrupters (GFCIs) in areas prone to moisture, such as bathrooms, kitchens, and outdoors, provides an added layer of protection by quickly cutting power if a fault occurs. It is also important to ensure that electrical outlets and wiring are properly installed and maintained. Avoid overloading electrical outlets, as this can lead to overheating and fire hazards. Finally, educating children about electrical safety, including not touching outlets or damaged cords, helps them understand the potential dangers.