At the time when this building was used as the fan house, instead of the steam-powered fan used in the house that is now the storage/pump house, a large electric-motor fan was set into the administration room. The fan was the largest model in Japan but so many accidents occurred with the coils of electrical appliances at that time, that they always had a standby steam powered fan. The safety lamp room, the administration office, the meeting room and the health check room were next to each other on the north and west side of the building. The traces of them can be seen on the westside wall of the building. On the southern wall of the building, there are traces that the building was connected to the storage/pump house opposite.