How much voltage or current is dangerous?

All QuestionsCategory: Electrical EngineeringHow much voltage or current is dangerous?
How much voltage or current is dangerous?Marcos Oliveira asked 3 months ago
From what I heard:
110V (or 220V, pretty much household voltage) is dangerous (i.e. it can kill you) I think there is consensus on this, no need to try
Supposedly 60V (old phone lines) is dangerous (never tried, only heard it once… I probably won’t try)
From what I know firsthand:

9V isn’t dangerous (I put a 9-V battery on my tongue, nbd… in fact it kind of hurts!)
1.5V can actually be quite shocking with enough current (fallen for one of those “Do you want some gum?” high school tricks…), but they sometimes don’t use 1.5V with low current levels, and some use a DC motor to vibrate and complete the trick.
So I guess there are two parameters here, voltage and current… but are there approximate numbers for how much that would be considered dangerous from each (or together, which I think would be strength)?
No old phone lines 48vDC has always been good since at least the 1950s, if your skin is wet you can feel it a little, as if it’s on your forearm. Now the loop voltage is 90-110V AC cycle 2 by 4 seconds (USA). Your bell will ring but it’s fine, if you touch the wires when someone calls you. The loop voltage rides on top of 48vDC, so it’s on the same conductors as the audio voltage (DC). Fortunately, a 4-second vacation will give you a chance to get off the drivers with a shriek (of pain).

1 Answers
How much voltage or current is dangerous?Anthony Riddle answered 3 months ago

The amount of dangerous voltage is not really a fixed number because it depends on your body’s impedance, exposure time, and the “hardness” of the source (i.e. how much current it can provide). You get numbers like 60 volts (or as low as 30 volts) and it’s an attempt to get an average number above ‘be careful’.
However, depending on how “plugged” you are at any one time, eg sometimes 50V might be perfectly safe and other times it might kill you.
DC or AC (and any frequency) seems to make a difference too, female or male, etc – this table is very helpful:
Table 1
Figures as low as 20 mA are given via the heart as fibrillating – here’s another table from the same source that gives the body’s resistance based on different situations:
Table 2
You can see that up to 20 volts can be dangerous under the right conditions.
This is the reference where the tables come from, I think it’s quite accurate based on some experiments that I did myself to measure body resistance. The rest of the site in general seems to be well informed and provided by the bits I’ve read, so I think this might be a quite reliable source.

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