Returning to IFC Section 907, we see that 907.2.1 addresses assembly occupancies, stating that a manual fire alarm system is required if the Group A portion of the building exceeds 300 people or ...

Fire alarm systems serve a vital purpose. But if installed incorrectly, they can fail to protect building occupants. Worse, some errors can increase the danger to building occupants. Thus, Art. 760 ...

Even if everyone was on the first floor, IFC 907.2.2 would require a fire alarm system; therefore, the Group B rules in IFC 907.2.2 mandate a manual fire alarm system in our example building.