Which one is the Danger, Current or Voltage?
Lets starts from Ohms’Law.
Ohm’s Law definition:
Ohm’s Law states that the current flowing in a circuit is directly proportional to the applied potential difference and inversely proportional to the resistance in the circuit.
First let me remind the ohms law,
V= I*R
V = Voltage in Volts
I = Current in Amperes
R = Resistance in Ohm’s

Ohm’s law shows that voltage is must to flow the current in a conductive material having some amount of resistance as almost all materials having some amount of resistance to the flow of electrons through it.

Lets come to the point:
The main cause is the voltage and current as an effect is the killer at specific rate for specified period. Current will kill you but some amount of voltage is required to flow that current in the body breaking the human body resistance. In other words, an enough power is required to pass in the human body for proper electric shock.
In short, high voltage with a few micro amperes cause nothing to the human body like in high voltage supplying cathode ray tube in traditional TV set or high static voltage in the comb. on the other hand high current with hundredth of ampere with ten, twenty or thirty or more make nothing to human bodies like electric welding machine as the amount of voltage is not enough to push that level of high current in the human body as there is a path with least amount of resistance as compared to the human body internal resistance.
Another example is the car battery having high amperage with low voltage level (12V DC) but if we tough both leads, it won’t electrocute. Therefore enough voltage of 100 and above with enough current make electric shock to human bodies because human body like resistor need enough power to pass current.

The following level of voltage are considered safe.
AC Voltage:
25V (Wet places)
50V (Dry places)

DC Voltage:
120V DC
The following tables shows the different values of AC and DC currents in mA and its effect on the human body. Keep in mind that it is the average value and not meant to be same for everyone as it depends on different factors.

AC in mA (50Hz)  DC in mA Effects on Human Body
0.5 – 1.5 0.4  Perception
1.3  14 – 15  Surprise
3 – 22  15 – 88 Let’s Go (Reflex Action)
22 – 40 80 – 160 22 – 40 80 – 160 Muscular Inhibition
40 – 100 160 – 300 Respiratory Block

More than 100 More than 300 Usually Fatal

About the Author


Hello! My Dear Friends. I am Subramanian. I am writing posts on androiderode about Electronics testing and equipments.

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