Final answer:
The minimum plumbing fixture requirements for assembly occupancies without permanent seating are determined by local building codes which reference standards such as the International Building Code or the Uniform Plumbing Code. These requirements are based on the number of occupants, and factors such as gender distribution and food service facilities may affect the fixture counts.
Step-by-step explanation:
For assembly occupancies such as theaters and auditoriums, in the case where there is no permanent seating, the plumbing fixture requirements are specified by local building codes, which often reference standards such as the International Building Code (IBC) or Uniform Plumbing Code (UPC). These codes specify a minimum number of plumbing fixtures based on the number of occupants.
For example, a certain number of water closets (toilets) and lavatories (sinks) may be required based on the maximum occupancy calculated for the space. Lecture halls and libraries are also subject to these requirements, where the fixture count may be based on either square footage or the expected number of users at peak times.
Fixture counts may also be influenced by factors such as the gender distribution of the expected users and the presence of food service facilities. To ensure full compliance, it's important for designers and builders to refer to the latest applicable codes and possibly consult with a local building official.