How many visual and audible notification appliances are required for occupancy loads of 150 units on the 5th floor?

When determining the number of visual and audible notification appliances required for an occupancy load of 150 units on the 5th floor, it is important to refer to the applicable codes and standards that outline the requirements for notification devices in buildings.

In general, the National Fire Alarm and Signaling Code (NFPA 72) provides guidelines on the minimum number of notification appliances based on the occupancy load and the layout of the building. For an occupancy load of 150 units, it is typically calculated that one notification appliance is required for every 100 occupants, with a minimum number of appliances specified to ensure adequate coverage.

Based on the common requirements, for an occupancy load of 150, the calculation may necessitate a certain number of appliances to ensure that both visual and audible alerts can be effectively communicated in case of an emergency. The specific number of 12 appliances aligns with the need to adequately cover the area while ensuring compliance with safety regulations, which address the significance of audible and visual notifications in facilitating occupant safety during evacuation scenarios.

While the other options present different figures, they do not meet the established criteria for sufficient notifications in relation to the given occupancy load, making 12 appliances the appropriate choice to ensure effective coverage and adherence to safety standards.