Fog huts are small 'sentry-box' style structures that were located close to most ‘distant’ semaphore signals to provide shelter for a ‘fog man’. The role of the fog man was to observe the state of the adjacent signal during times of poor visibility (e.g. during fog and periods of falling snow) and to place / remove a detonator on / from the running-rail each time the signal changed. The exploding detonator provided the locomotive crew with an audible warning that the signal ahead was ‘on’ (i.e. at danger). All of the surviving fog huts within the SCRCA are tall, thin structures constructed from pre-cast concrete panels topped with either a pre-cast concrete, asbestos or felted timber roof.
For the purposes of the SCRCA Project, all structures fitting this description are currently being categorised as fog huts. However, it is clear that at least some of these structures were converted for use as trackside toilets at some point in their history.