How do you know how much voltage is deadly without knowing the actual current? For example, a stun gun generates a 50kV with only 2 milliamps worth of current. But on the other hand, a small generator can produce 15kV of voltage. Obviously I'm going to say the generator is more deadly, but I don't actually know the current flow. Basically my question is, when reading a voltage rating, how can you really relate the total amount of energy without knowing the current?