Is it harmful to be electrocuted?

In school, many children always play pranks. Recently, one prank has become very popular. It is to give charged ballpoint pens to other children, and the other children will be shocked when they press the switch. Although this is just a little joke between children, adults should be careful because even a slight electric shock can cause harm to the body. Although it is not very obvious, it still requires attention. So, what are the harms of being electrocuted?

(1) Current type: Current is divided into alternating current and direct current. The danger of electric shock from alternating current is greater than that from direct current, but when the voltage is too high, direct current is more dangerous because it can cause rigid muscle contraction and cardiac arrest, with a high mortality rate.

(2) Current intensity: 1-2 mA current can cause tingling sensation; 15-20 mA current can cause tonic contraction of muscles, but the power source can be disconnected; 20-25 mA current can cause contraction of the flexor muscles of the hand, but the power source cannot be disconnected, causing hand burns, and respiratory muscle contraction can cause breathing difficulties; current above 50 mA, if passing through the heart, can cause ventricular fibrillation or cardiac arrest, and can also cause respiratory muscle spasm and respiratory arrest; current above 100 mA passing through the brain can cause loss of consciousness.

(3) Voltage level: When the skin is dry, a safe voltage is below 24V. The higher the voltage, the greater the current generated, and the greater the damage to the human body. DC voltages below 380V rarely cause casualties; AC voltages above 65V are dangerous.

(4) Resistance: The smaller the resistance, the greater the current passing through and the more serious the tissue damage. The tissues with increasing resistance are nerves, blood vessels, muscles, internal organs, skin, tendons, fat, and bones.

(5) The path of electric current in the body: When electric current flows from one upper limb to the other upper limb or lower limb, the current passes through the chest, which is more dangerous than when the current flows from one lower limb to the other lower limb. Also, because the heart is on the left side of the body, electric current passing through the left side of the torso is more dangerous than the right side.

(6) Current contact time: The longer the current passes through the human body, the more serious the damage to the body.