For those unfamiliar with the modern style of European ES holder here is an example:
[Linked Image]
[Linked Image]

As has been said above, the screw shell doesn't make contact with the circuit until it's screwed right down into the holder.

As in Ireland, however, the BC lamp is by far the most common in most domestic fittings, and with a symmetrical double-contact fitting polarity is of no importance.

One point that used to be of concern though is the bedside or tablelamp which incorporated a switch at the holder. These days, they're fitted with the standard BS1363 plug and color-coded cordage making it easy to connect the hot side to the switch.

Back in the "old days" though, such lamps were commonly wired with twisted twin flex with no polarity identification. Even if coded cords were used, many were fitted with the reversible 2-pin 5A plug, making it impossible to guarantee placement of the switch in the hot conductor.

Obviously it would always be advisable to pull the plug before fiddling with the lampholder, but there would always be someone who would assume that because the switch on the holder was off that they could touch the contacts in safety.

[This message has been edited by pauluk (edited 05-18-2003).]