Ordinary hazard areas are sprinkler-protected under what condition?

• A. Sprinklers are never allowed.
• B. Sprinklers are permitted under any condition.
• C. Sprinklers are permitted under specific compartment conditions.
• D. Sprinklers must be dry-type.

Answer: (C)

The idea being tested is how ordinary hazard areas are allowed to be sprinkler-protected in a low-rise residential system. In NFPA 13R, you don’t blanket-sprinkle every ordinary hazard space by default. Instead, protection is allowed when the space is divided into clearly defined sprinkler compartments by fire barriers. Each compartment is a separate area that can be individually protected, with its own allowed area, ceiling height, and required sprinkler layout. This compartmentalization lets you limit the extent of protection and water damage to the specific area, rather than applying sprinklers to the entire floor or building.

So, ordinary hazard areas are permitted to be sprinkler-protected under specific compartment conditions — not automatically in every space, not never, and not restricted to dry-type systems.