Visited the bunker yesterday (maintenance on Sump Pump backup power supplies) and had time for a look at some of the lights in the plotting room. They are Holophane lights and have two 100watt bulbs in each (marked Property of H.M. Government) except for some of the High up ones which have four.
That totals up to over 4000watts of lighting in there!! Miraculously they’re all complete except for two missing side panels (easily replaceable) and one pressed glass diffuser panel (probably very difficult to replace). There are patent numbers and a design number on the pressed glass panel so hopefully I’ll be able to find out more about the lights. (age etc.) It seems that Holophane still exist so will contact them to see if they can help.
The last light is from one of the smaller corridors – haven’t had time to look at this more closely yet but looks like a two bulber as well.