(a response to the experience of photographing in Vernon House, an unoccupied 21 storey apartment building)
You can buy a domestic smoke detector of the type approved by local fire services from most local DIY stores. This is the type that is typically takes the form of a white disk maybe an inch thick, with a grille about the diameter of your palm. They typically have a small adhesive pad that allows you to attach them to a ceiling, though they can also be screwed in place. They are invariably powered by 9v batteries (the small rectangular ones with two terminals on the top surface, making it possible to put your tongue across them, receiving an uncomfortable electric shock).
These batteries last a long time, the energy consumption of the alarm unit being relatively low, but they do eventually fail. Since these fire alarms are normally silent and inert in operation (until triggered by smoke particles) it is of course important that once the batteries of these devices run dangerously low (threatening to render the alarm functionless), that there is some form of warning signal to alert the building’s occupier of this fact, so that the battery can be replaced. Although this warning signal could take a number of forms, an auditory warning is perhaps the least easy to miss or ignore and the manufacturers have opted for such a warning.
It takes the form of a periodic electronic “chirrup”. This chirrup lasts only a fraction of a second and is relatively infrequent, however, it is frequent enough and piercing enough to induce anyone forced to spend any extended period of time in proximity to it, to act and remove the failing battery (in the case of the responsible householder, replacing it with a fresh one).
One of these chirruping alarms is – from experience – an annoyance which will sooner rather than later prompt a response from you. The chirrup has presumably been designed to consist of a noise with which you do not want to co-habit and it is effective in this regard.
If you had fitted two of these alarms (maybe one upstairs and one down stairs) in a domestic property and if you had fitted their batteries at the same time, it is plausible, likely even, that you might experience two repeated, interspersed battery warnings, the chirrups of the two detectors working in relay.
Let’s now imagine a building on a different scale altogether, but quite a realistic proposition nonetheless. This is a building with around 120 apartments spread over some twenty floors, in all of which have been fitted smoke alarms. This building has been left unoccupied and untended for about eighteen months. The batteries have run low on all of the smoke detectors and almost all 120 of them are chirruping, not in unison, but at slight and irregular intervals of maybe a few seconds:
The building’s already poor sound-proofing has been rendered poorer still by the fact that the local police have used the building repeatedly for “siege training”, as part of which they have smashed in almost all of the already flimsy apartment doors. This means that from almost anywhere in the building, you can hear this irregular chorus, each source placed at a variable distance from you the listener: to your left and right, in front and behind you, above you and below you; receding, spread across many floors.
The chorus is however most penetrating (and unsettling) if you stand in the central stairwell of the building, which is made of concrete (concrete stairs, concrete walls, metal banister) and runs unobstructed, an echoing, damp column of air that rises nearly lightless like a malignant spinal-cord through the core of the building, from basement to roof.
As you move through the building; its stairwell, its landings, its rooms, you move simultaneously toward and away from isolated nodes and clusters of sound. The sound remains fugitive somehow, since you can only be in one place at a time and once you locate one sound-source all the others then exist elsewhere, like echoes or phantoms; receding to the edge of hearing.
Now, begin to move slowly through this building.
Move hesitantly, because you cannot be wholly sure that you are alone. People do break in occasionally to steal one of the few remaining copper hot-water tanks. Try to ignore the fact that for your own safety you have been locked in. You have the caretaker’s number, but the reception in the building is not good.
No one else knows you are here. Breathe. slowly.