Tha
Thanks for the advice . No RCD protection in the property. I also have the option of placing the RCD Spur outside the bathroom . I think from the edge of bath to wall is around 35 - 40 cm.Any of the 'standard' fittings like this are regarded as IP20, which can't be used in zone 1 or 2 (so up to 60cm from the side of the bath). Outside of that they are ok for general use in a bathroom as long as they are not likely to be sprayed with water.
PVC trunking is OK in zone 2 to run cables through, though it shouldn't have any joints within it as it doesn't have an IP rating for water resistance (that I know of).
There is an extra wrinkle here though - the RCD spur you show is currently not listed in the Wiring Regulations as an acceptable way to add 'additional protection' in a bathroom, though there is conflicting information as to whether this was an error or deliberate.
Some people would say that means it can't be used on new installations to comply, but requires a more traditional RCD or RCBO protection
I still take the view that there are places where it is reasonable to use it, though adding more traditional RCD protection is a better option when it's available.
Is there any RCD protection in the property?
One final point - any work within the zones in a bathroom is notifiable under the Part P Building Regulations scheme, which generally means it has to be done by a registered person in the competent schemes.. There are other ways by notifying it yourself, but they can be costly...