The Speed at Which Human Contact with Home Electrical Power Can Prove Deadly: Examining Electricity's Lethal Velocity
In our daily lives, we often take electricity for granted, but it's essential to be aware of the potential dangers it poses. One such danger is electrical shock, a phenomenon that can lead to severe injuries or even death.
An electrical shock occurs when a person becomes part of an electrical circuit. This can happen due to a short circuit, creating a high-energy explosion of heat and light, known as an arc flash. Such events can cause severe burns, blindness, and even death [1].
The severity of an electrical shock depends on several key factors. The most crucial factor is the current magnitude, which determines the amount of electricity flowing through the body. The path the current takes through the body, the duration of contact, the frequency of the alternating current, and an individual's health also play significant roles [2].
Electricity, seeking the path of least resistance, can flow through the body, potentially disrupting vital organs and causing severe tissue damage. The longer the duration of the contact with the electrical source, the greater the damage [3].
Currents as low as 50 to 150 milliamps (0.05 to 0.15 amps) can cause extreme pain, respiratory arrest, severe muscle contractions that prevent letting go, and death is possible in this range. Higher currents (1 to 4.3 amps) are likely to cause ventricular fibrillation, a rapid and uncoordinated heartbeat that stops effective pumping of blood, and death [2].
Household currents are typically alternating current (AC) at 110 or 230 volts and frequencies of 50 or 60 Hz. Such AC applied through the chest for more than one second can be fatal [1][3].
In summary, a current over the chest for more than one second can cause ventricular fibrillation, leading to death [1][3]. The lethal current range is roughly 50 to 150 mA, which can cause possible death, and 1 to 4.3 A, where death is likely [2]. The most common cause of death is ventricular fibrillation, where the heart's pumping becomes ineffective [3].
Immediate release from the current is critical to avoid fatality. If a person cannot let go due to muscle contractions, the risk of death increases rapidly [2].
To minimise the risk of electrical injury, it's crucial to follow proper safety precautions. These include using ground fault circuit interrupters (GFCIs), inspecting electrical cords and appliances, avoiding overloading electrical outlets and circuits, turning off power at the breaker before working on any electrical equipment, using insulated tools, maintaining a safe distance from overhead power lines, hiring a qualified electrician for any electrical work, ensuring proper grounding, using surge protectors, and keeping electrical equipment dry [4].
A current path from hand to foot is particularly dangerous because it increases the likelihood of the current passing through the heart. Therefore, it's essential to be aware of these dangers and take the necessary precautions to stay safe.
References:
[1] National Fire Protection Association. (2020). NFPA 70E Standard for Electrical Safety in the Workplace. Retrieved from https://www.nfpa.org/global/default.asp?url=/Codes-and-Standards/All-Codes-and-Standards/Electrical-Codes-and-Standards/NFPA-70E
[2] Occupational Safety and Health Administration. (2021). Electrical Safety. Retrieved from https://www.osha.gov/SLTC/etools/electrical/hazards/electrocution/index.html
[3] American Heart Association. (2021). Electrical Injuries. Retrieved from https://www.heart.org/en/health-topics/cardiomyopathy/about-cardiomyopathy/electrical-injuries
[4] Electrical Safety Foundation International. (2021). Electrical Safety Tips. Retrieved from https://www.esfi.org/electrical-safety-tips
Science highlights the potential dangers of electrical currents, particularly in medical conditions. A current over the chest for more than one second can cause ventricular fibrillation, a rapid and uncoordinated heartbeat that can lead to death [1][3]. In health and wellness, understanding and abiding by safety precautions, such as using ground fault circuit interrupters (GFCIs), inspecting electrical cords and appliances, and maintaining a safe distance from overhead power lines, can help minimize the risk of electrical injury [4].
