045 - A floor alarm lantern. If you have a "Prompt" alarm on the ground or basement area, one of the red lamps would show something like,
G01 or B01 a Power alarm "PWR" would be blue. There was one at Fort Southwick very similar to this in the telecoms tunnel.

019 - The 'Ground Floor' is the above ground part of the building.

009 - Double set of blast doors made from what appears to be about 5mm gauge steel. This is the entrance lobby looking towards the ground floor audio equipment and RDF (repeater station distribution frame) area. Directly opposite is a single blast door to a corridor with welfare, offices, and work rooms.

017 - Halfway down the steps looking into the basement area. The doors on the left are for the transformer rooms the one on the upper right leads to the engine room.

013 - Sign showing the underground locations.

016 - The stairway where the previous photo (017) was taken from.

014 - Chain hoist for moving equipment between levels.

011 - A pressure gauge used to check that positive pressure is maintained within the protected area. It was made by 'Casella Measurement', a firm that still exists. Neal Hill, the Product Marketing Manager, tells me that:

"According to the Casella London 1955 Catalogue (no 808), it is an inclined water gauge (manometer) for measuring pressure (over a range of 0-1.5 inches H₂0). It is said to be more accurate than the more traditional U-tube type manometer which tend to work over a bigger range. There is a handwritten note showing the price as £6 17s 6d".