The details of this also vary based on where you're at. In the US, neutral is bonded to earth at every house I think. In Europe, neutral is only bonded to earth at a local power station.
The US system is somewhat unique and lacks heaps of safety features: I am guessing mostly because a 110V shock is far less dangerous than a 240V shock (Although higher amperages mean higher risk of fire?).
For example for UK, EU and NZ etc: sockets and pins have a variety of features to avoid touching the phase (live) wire with say a screwdriver or knife in hands of a child.
For example, all new circuits installed in New Zealand since 209 must have an Residual Current Detector (the actual rules lead to multiple RCDs per main power board). This will cut the circuit if someone does manage to touch a live wire somehow (current from phase to neutral doesn't match, because some of it is grounded through your body, and the mismatch triggers the breaker. Wayyyyyyy safer than a fuse!
In the US there is tamper proof outlets and GFCI is equivalent to RCD. Its pretty much required for new houses though older houses may vary on what they implement.
Are tamper proof outlets mandatory? The UK has had shutters on the phase that is opened by the earth pin forever. Which is why their plugs are caltrops, and have a plastic earth pin if double insulated (only phase and neutral wired, with no earth wire).
I don't think I have ever seen a US plug where the pins have a non-conductive protective covering at the base of the pin (I think all modern UK and NZ male plugs have that. Although I'll be honest that I think the NZ solution makes plugs less safe due to risk of pins bending then breaking and leaving a live metal pin exposed in the socket).
EU sockets are mostly recessed from what I have seen (some NZ sockets are, but the recess is still is often unusable with old plugs, so is not common yet, but will become so as more plugs are sold that fit properly).
> The UK has had shutters on the phase that is opened by the earth pin forever. Which is why their plugs are caltrops
No, bad design is why they are caltrops. Over here in the Netherlands shutters are similarly required but none of our plugs need a third pin. The shutter is a see-saw construction that works in such a way that you need to insert both prongs at the same time for the shutter to rotate out of the way.
That said our grounded plugs are still caltrops for no real good reason, though less so than the UK ones. They tend to fall with the prongs to the side instead of prongs-up.
Its required by current US NEC code but older house are grandfathered in unless they do major renovation. Also some exceptions like outlets high enough to be out of reach of kids.
Its possible that the UK/NZ plugs have better designs. The code improves step by step here.
