Dr Ahmed Taher made a Computational Fluid Dynamics model to demonstrate the means by which the ventilation system of a typical Carnegie Library building was originally designed to work. The model is based on Cradely Heath Library, which features a ventilating turret at the apex of its vaulted reading room ceiling to extract the “vitiated” air. At low level, positioned beneath each window and behind each radiator, a series of cast terracotta vents admit fresh air to the room.
The movement would have been powered by an electric fan housed in the ceiling beneath the turret such as the one illustrated below. The aim was to ensure a continuous flow of fresh air in order to prevent the spread of disease.