Micc or FP200 cable in chapels or churches ?

Usually down to the preferences of the particular denomination - I think the C-of-E for example had some national guidance. In practice a lot probably depends on the particular building - a 11th century structure with half a forest of exposed timber holding up the roof probably needs rather different consideration to a new build "Kingdom Hall" that you could probably treat more like modern office space. In the middle you have the victorian era builds that have undergone varying amounts of modern renovation.

  - Andy.

This is usually a matter of what can be granted as a dioscean faculty, and will depend on the age and materials of the building.

https://electrical.theiet.org/media/1449/religious-buildings_interview.pdf maybe worth a read

Mike,

I have modified and added to wiring in a  small listed C of E church and it was done in T&E. I do not think there is any particular rule and is probably dependent on the insurer and the significance of the building. I did quote for rewiring it in MICC  and replacing all the lighting but it was too expensive so it still has T&E, no fire alarm and oil fired heating 15 years later. The C of E have a department that look after their estate, you would have to ask the vicar about contact details. I was told, after I had completed the work, that I should not have been authorised to do the work as I was not registered with a particular trade organisation. 

No idea about other denominations but would have expected them to all have an estates department.