Sorry Andy... didn't read your comment properly.
Yes... Fire Safety (Part B) and Sound Transmission (Part E) of the Building Regs.
This is one of those fuzzy, grey areas. If yours is a "new-build", then the Regs would apply. That wouldn't apply necessarily to existing dwellings.
Building Regs compliance can't be forced retrospectively.
However, if changes are being made that might affect the "integrity" of the ceiling, then a case could be argued that the changes should comply.
Between you and me... that would effectively render all sale of non fire-rated fittings illegal. Welcome to the world of Building Regs interpretation :o)
If concerned, then go here..................
http://www.toolstation.com/shop/Lighting/Fire+Rated+Downlights+Mains/d220/sd3289