Lamp post fed from communal supply

Depends on the design of the lamp post - modern steel tube ones are normally earthed, very old cast iron ones used to sometimes be considered to be their own electrode, this is not really acceptable as paint and cement mean that does not really work, Is the cabling and fixtures within all double insulated or equivalent so its class II ? Is there a stud that looks like a terminal that has been ignored ?
When street lamps are connected unmetered and get a concentric CNE supply opinions and practice over the years has varied by DNO if it is better or not to connect the combined neutral earth to the lamp post body. However this I presume is a 3 core (LNE ) supply even if TNC-s at the origin, so PME direct to small load is not the case and it can be earthed.

Mike.

Mike.

If the lighting "head" is Class I - there's likely to be an automatic bond to the column itself ... although technically that's not necessarily needed if everything inside is enclosed/sheathed.

Small c.p.c.s connected to outdoor metalwork stuck in the ground can raise an interesting potential problem with PME diverted N currents ... if the resistance of the column to Earth happens to be particularly low. Class II heads and everything sheathed/enclosed inside the column can seem attractive in such cases.

   - Andy. 

Are they RCD protected? Whilst this might not have been a requirement when the street lamps were installed, after some incidents, Section 714 of BS 7671 has required RCD protection (residual current rating not exceeding 30 mA) for outdoor lighting accessible to the public (with one or two exceptions) since BS 7671:2018+A2:2022.

It might be worth re-evaluating risk assessments if you don't have RCD protection.

Yes they are (RCD) Residual Current Device protected and accessible to the public, though it is private land.