According to various sources something as little as 0.01A = 10mA can be painful, at 0.1A = 100mA you can expierence *
- "ventricular fibrillation of the heart".
- "an uncoordinated twitching of the walls of the heart's ventricles which result in death".
- "As well as other painful things such as extreme breathing difficulties, Severe Shock, Muscular paralysis ...". *
How is that true? I've worked with an arduino and LEDs, LED Strips etc for quite a while yet never heard that 10mA can be painful let alone 50-100mA deadly.
Answer
First off, its voltage not current that kills (because you have to bypass the skin). The actual mechanism is current once you get under the skin.
The minimum current a human can feel depends on the current type (AC or DC) as well as frequency for AC. A person can feel at least 1 mA (rms) of AC at 60 Hz, while at least 5 mA for DC. At around 10 milliamperes, AC current passing through the arm of a 68-kilogram (150 lb) human can cause powerful muscle contractions; the victim is unable to voluntarily control muscles and cannot release an electrified object.[11] This is known as the "let go threshold" and is a criterion for shock hazard in electrical regulations.
Source: https://en.wikipedia.org/wiki/Electrical_injury
Your not getting 10mA through your heart when you are playing around with electronics or low voltage <60V. Skin is more than 10k (as much as 100k), to get 10mA through 10k is at least 100V. If you have dry skin, it is much higher.
Per IEC directives Low voltage is lower than 50V
In the European Union, the Low Voltage Directive defines low voltage starting from 50 V AC, and 75 V DC. The directive only covers electrical equipment and not voltages appearing inside equipment or voltages in electrical components. IEC 60364 defines it as 50 V AC and 120 V DC.
Source: https://en.wikipedia.org/wiki/Extra-low_voltage
The body has resistance to current flow. More than 99% of the body's resistance to electric current flow is at the skin. Resistance is measured in ohms. A calloused, dry hand may have more than 100,000 Ω because of a thick outer layer of dead cells in the stratum corneum. The internal body resistance is about 300 Ω, being related to the wet, relatively salty tissues beneath the skin. The skin resistance can be effectively bypassed if there is skin breakdown from high voltage, a cut, a deep abrasion, or immersion in water (Table (Table2).2). The skin acts like an electrical device such as a capacitor in that it allows more current to flow if a voltage is changing rapidly. A rapidly changing voltage will be applied to the palm and fingers of one's hand if it is holding a metal tool that suddenly touches a voltage source. This type of contact will give a much greater current amplitude in the body than would otherwise occur.
Source: https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2763825/
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