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.