The amount of electrical current that can be deadly to a human being varies depending on several factors, such as the path of the current through the body, the duration of the exposure, the voltage, the individual's health, and resistance. It's important to note that the concept of lethality in terms of a specific number of coulombs is not straightforward because coulombs measure the quantity of electric charge, not the potential harm.
Current is measured in amperes (amps), and it's the amperage that poses the greatest risk to human life. The human body's resistance to electric current can vary, but typically, currents as low as 100 milliamps (0.1 amps) can cause significant harm and can be fatal under certain conditions. Currents above 10 amps are almost always fatal.
Instead of focusing on a specific number of coulombs, it's more relevant to be aware of the potential danger of electric current at different levels:
- 1 milliamp (0.001 amp) or less: Generally not felt by most people.
- 1 to 5 milliamps: Can cause tingling sensations.
- 6 to 25 milliamps: Can cause muscle contractions, making it difficult for a person to let go of the source of shock.
- 25 to 100 milliamps: Can lead to breathing difficulties, particularly if the current passes through the chest area.
- 100 milliamps to 1 amp: Can cause ventricular fibrillation (an irregular heart rhythm), which can be fatal without immediate medical attention.
- 1 amp and above: Can cause severe burns, paralysis, and are almost always fatal.
These values are approximate and can vary depending on individual factors. It's essential to treat electricity with caution and follow safety guidelines to avoid the risk of electrical accidents. If you suspect someone has suffered an electric shock, seek medical assistance immediately.