Final answer:
Humidity level of the room is the factor that does not dictate the size of a darkroom; other factors like the volume of radiographs, type of equipment, duplication space, and user capacity are directly related to darkroom size.
Step-by-step explanation:
The size of a darkroom is influenced by various factors needed for the operation and functionality of radiographic processing. However, not all listed factors are relevant to the size of a darkroom. Specifically, the humidity level of the room is not a direct factor in determining its size.
Though important for the proper development of radiographs, humidity levels can be controlled within a space of any size and thus do not dictate the overall dimensions of the darkroom. Important considerations such as the volume of radiographs produced, the type of processing equipment used, the space required for duplication of films, and the number of persons using the room are all directly correlated with the size requirements for an efficient and effective darkroom in a medical or photography setting.