mapj1: 
 

Generally “the zones”  stop at fixed partitions, walls and so on that do not move, and at the entrance door to the bathroom - as the assumption is presumably that it would be immodest to shower with the door open, and all these objects will intercept water splashes .

Now as an aside   I'm not sure that the writers of the regs are particularly worldly wise or well traveled sometimes in the assumptions made about behaviour like that, but there we are.

"Presuming an assumption" is asking for disaster, according to the laws of Engineering! Ignoring the adage ‘Assumption is the mother of all cuffups’ is sure to invoke Murphy's Law.

The real reason the location containing the bath or shower stops at a fixed partition or door is quite simply, it's considered to be an indicator of the extent or boundary of the location. The issue being how do you define such a location? You run the risk of unintentionally including a whole structure. It's not an easy debate, and one that I'm sure will cycle round for further debate when any work is done on Section 701 (or IEC 60364-7-701 internationally).

Yes, it does lead to some socket-outlets, switches, etc., outside of the location potentially being within the proscribed distances [if the door is open] but on the other hand, practicability tells us that the bathroom light switch not being outside the bathroom might be more of an issue than the far-fetched risk of someone trying to operate it from within the bath or shower.

mapj1: 
 

Generally “the zones”  stop at fixed partitions, walls and so on that do not move, and at the entrance door to the bathroom - as the assumption is presumably that it would be immodest to shower with the door open, and all these objects will intercept water splashes .

Now as an aside   I'm not sure that the writers of the regs are particularly worldly wise or well traveled sometimes in the assumptions made about behaviour like that, but there we are.

"Presuming an assumption" is asking for disaster, according to the laws of Engineering! Ignoring the adage ‘Assumption is the mother of all cuffups’ is sure to invoke Murphy's Law.

The real reason the location containing the bath or shower stops at a fixed partition or door is quite simply, it's considered to be an indicator of the extent or boundary of the location. The issue being how do you define such a location? You run the risk of unintentionally including a whole structure. It's not an easy debate, and one that I'm sure will cycle round for further debate when any work is done on Section 701 (or IEC 60364-7-701 internationally).

Yes, it does lead to some socket-outlets, switches, etc., outside of the location potentially being within the proscribed distances [if the door is open] but on the other hand, practicability tells us that the bathroom light switch not being outside the bathroom might be more of an issue than the far-fetched risk of someone trying to operate it from within the bath or shower.