Effect of electric shock on the human body
If a person accidentally gets an electric shock to a 100V outlet or electric wire, how much current will flow through the body? The resistance value of a person is said to be 2000Ω to 4000Ω. The resistance value changes depending on the difference in physique, whether the skin is dry or wet, or the part of the body that has been electrocuted. Roughly speaking, 2000Ω is when a small, thin person is sweating, and 4000Ω is when a large person is dry.
When calculating the current value from Ohm’s law
I (A) = V / R = 100/2000 = 0.05A = 50mA, and a current of 50mA will flow through the human body.
So how shocking is 50mA?
The following information was found on the “Workplace Safety Site” of the Ministry of Health, Labor and Welfare. According to it, 1mA makes you feel light electricity, 5mA makes you feel pain, and 50mA flows into the human body, “there is a possibility of fainting or cardiopulmonary arrest.” Cardiopulmonary arrest is when the heart is in the path of electric shock, but it is life-threatening.
I think that electric shock is more dangerous at higher voltage than current, but direct voltage is not related to electric shock. The proof is that the electrostatic voltage exceeds 3,000V, but the current value is so small that it just snaps. Whether or not you die from an electric shock depends not on the power supply voltage but on the current flowing through your body.
Although the smartphone charger is 5V, it can output a current of about 1A, so if you put the tip of the charging plug in the bath water, you may get an electric shock.
In fact, a 12-year-old Russian boy dropped his charging iphone into a bath and was electrocuted, a 16-year-old girl was electrocuted with headphones while charging his smartphone in Thailand, and a smartphone charging while taking a bath in France. A 15-year-old girl has an electric shock death accident. In the case of a 16-year-old Thai girl, her body was burned and she died instantly. It is very dangerous to operate your smartphone while charging. The charger should never be taken to the bath.
Then, isn’t there an electric shock death in the “electric bath” of the public bath? Since the electric bath runs electricity, I am “electrically shocked”. Generally, the voltage of the electric bath is 3V to 10V and the current is about 1mA to 10mA. The power supply for the electric bath is a constant current power supply so that no more current flows.