Fire sprinkler discharge must not be blocked by obstructions unless which condition is met?

The requirement regarding fire sprinkler discharge being unblocked by obstructions hinges on the effectiveness of the system in protecting occupants and property from fire hazards. When additional sprinklers are installed, this addresses the potential issue of insufficient coverage caused by the obstructions. The purpose of multiple sprinklers is to ensure that even if one is obstructed, other sprinklers can still adequately cover the area, providing necessary protection and maintaining the intended fire suppression capability.

Moreover, the installation of additional sprinklers allows for a more comprehensive strategy in fire suppression, ensuring that any areas previously considered unsafe due to obstruction can now be effectively serviced by the fire protection system. This is critical because fire safety codes, including those in the International Residential Code, are designed to minimize fire risks and maximize life safety.

In contrast, the other options do not establish adequate measures for maintaining sprinkler effectiveness. Simply stating that the area is not used, that obstructions are temporary, or that the building is small does not sufficiently address the core need for fire suppression capability and may not ensure safety in the event of a fire.