By contrast with your 6 combined volts, the average house current is 110V, 60Hz alternating current. If you grab ahold of some, depending on how well you are grounded (standing in water) or not grounded (wearing rubber soles) the current may pass through you seeking its path to ground because you represent the path of least resistance.

Under these conditions with 60Hz AC, the following values apply:

1 mA        Barely perceptible
16 mA        Maximum current an average man can grasp and "let go"
20 mA        Paralysis of respiratory muscles
100 mA        Ventricular fibrillation threshold
2 Amps        Cardiac standstill and internal organ damage
15/20 Amps        Common fuse or breaker opens circuit*

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