Electrical safety

Voltage 20 to 30 and a current of 16 mA, 60 Hz are 'Let go' current. Voltage and current of higher value produce electric shock. 50 mA, 60 Hz : pain, fainting and exhaustion. Body (skin) resistance vary from person to person. Women are more sensitive to electric shock. Even 18 V AC can be fatal. Shocking effect of an ACV and 3 times DCV are equal.

Insulation of live wire are degraded by Ozone, UV light, nuclear radiation, heating, acids (HCl), vibration, mechanical damage, biological reasons (eaten by insects) etc.

Neils Bohr and his son got Nobel prize in Physics in 1922 and 1975.