Flush fit ceiling lights

[ronecc1]

I just need an explanation. My daughter is having a new kitchen fitted. The fitter has, I presume taken a feed for the cabinet lights, from one of the ceiling lamps. He says he cannot refit the lamp because it does not meet current regulations and I don't doubt him. He say's that because the bulbs are open to the ceiling space, they should be changed to ones that have a 30 minute safety level, if there is a room above.
Can somebody explain why a bulb, that is open to an air space, like between floors, overheat quicker than one that is enclosed in a fire protective cover.

[Mr White]

It doesn't is the simple answer.
You are misunderstanding the "problem" it's nothing to do with the lamp. It's to prevent the spread of fire. If there is an "uncovered" ceiling light the flames from the fire can go around the lamp through the fitting and ignite the floor above from underneath, as well as ignite anything else, if the light fitting has a fire hood, or is fire rated then flames can not go that way. Standard plasterboard is fire rated for 30 minutes, it can not maintain that if there is a hole in it.

[ronecc1]

Thank's Mr. White, that explains it. Cheers.