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If we have a boost converter that increases a 1.5 Volt battery voltage to 100 Volts at the output and the battery is let us say theoretically capable of continuously providing 1A of current, would that make it dangerous to touch the 100 Volts at the output? The input would be 1.5 Watts at a maximum giving the maximum output current as 15mA. From my understanding this would be dangerous so a 1.5 Volt battery with such specifications could potentially harm you or worse? Is my understanding correct?

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  • \$\begingroup\$ Are you asking from a scientific/biological point of view? Or from a regulations/legal point of view? (I guess both would be on-topic) \$\endgroup\$ Commented Sep 23 at 15:38
  • \$\begingroup\$ From a "If i wanted to design a boost converter could i do harm to myself accidentally with a 1 volt battery" point of view \$\endgroup\$ Commented Sep 23 at 15:39
  • \$\begingroup\$ GFCIs tend to have a 30 mA threshold in the UK, though that's for AC. I wonder if the DC number would be different? \$\endgroup\$ Commented Sep 23 at 15:39

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I located this table on The Physics Factbook - Electric Current Needed to Kill a Human: -

enter image description here

So, 15 mA probably won't kill you but it's not going to be a nice experience and users should be protected from making contacts with the terminals that provide the 100 volts and potentially 15 mA. The chart below came from DSO electric - electric shock safety: -

enter image description here

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  • \$\begingroup\$ So in conclusion a 1.5 volt battery with such specifications could kill a person? So if I were to design a boost converter I should be careful about touching the terminals. \$\endgroup\$ Commented Sep 23 at 15:43
  • \$\begingroup\$ A 1.5 volt battery on it's own is safe but your circuit can generate 100 volts and that's near enough voltage to overcome the skin's surface resistance and penetrate current to the wetter internal organs and muscles @LEXORAI \$\endgroup\$ Commented Sep 23 at 15:45
  • \$\begingroup\$ So it's the additional energy stored in the capacitor that ends up being dangerous? \$\endgroup\$ Commented Sep 23 at 15:46
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    \$\begingroup\$ Hard for me to wrap my head around the fact that a dangerous circuit can be made using only a 1.5 volt battery \$\endgroup\$ Commented Sep 23 at 15:47
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    \$\begingroup\$ Trust the numbers. Percieved size is not everything. In the legend David slew Golliath with a pebble. \$\endgroup\$ Commented Sep 23 at 22:03
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That 100 V output is not something to take lightly. Even though a 1.5 V, 1 A battery only supplies about 1.5 W, which translates to roughly 15 mA available at 100 V, that’s already in the range of current that can give painful shocks and, under certain conditions (wet skin, current through the chest), can be dangerous. It’s not a supply that can push amps at 100 V, so it’s not "instantly lethal", but it can still cause muscle lock-up and pain. Plus, output capacitors can store charge and discharge suddenly. The limited power reduces the risk, but 100 V is still a voltage you should respect and handle with proper precautions.

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If you touch the 100 V to such body parts, so the body resistance is low enough to draw 15 mA at 100 V, then yes, this can be painful or even harmful/lethal.

Depending on the design of the converter, it might be able to output more current, as resistance drops, so perhaps the same battery could even supply a larger current, once the initial 100 V circuit erodes the more resistive skin parts.

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    \$\begingroup\$ 15 mA is unlikely to be lethal unless it passes through your heart. Not saying it couldn't be, but I think most people would survive. \$\endgroup\$ Commented Sep 23 at 15:48

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