Which sprinkler has RTI of 50 m^1/2 or less?

Which sprinkler has RTI of 50 m^1/2 or less?

• A. Quick-Response (QR) Sprinkler
• B. Design Discharge
• C. Grade Plane
• D. Heat-Actuated Device

Answer: (A)

RTI, or Response Time Index, measures how quickly a sprinkler responds to heat. A lower RTI means faster activation, which is crucial for early fire detection and protection in living spaces. Quick-Response sprinklers are specifically designed to have RTI values of 50 m^1/2 or less, making them faster to react than standard types. In NFPA 13R residential designs, this faster response is a key reason Quick-Response sprinklers are preferred—they help control a fire sooner, improving occupant safety in low-rise homes. The other terms don’t denote a sprinkler type with a defined RTI threshold: Design Discharge refers to the calculated water flow for the system, not a sprinkler’s reaction speed; Grade Plane is a layout concept unrelated to RTI; and Heat-Actuated Device describes the activation mechanism but does not specify the RTI value.

RTI, or Response Time Index, measures how quickly a sprinkler responds to heat. A lower RTI means faster activation, which is crucial for early fire detection and protection in living spaces. Quick-Response sprinklers are specifically designed to have RTI values of 50 m^1/2 or less, making them faster to react than standard types. In NFPA 13R residential designs, this faster response is a key reason Quick-Response sprinklers are preferred—they help control a fire sooner, improving occupant safety in low-rise homes.

The other terms don’t denote a sprinkler type with a defined RTI threshold: Design Discharge refers to the calculated water flow for the system, not a sprinkler’s reaction speed; Grade Plane is a layout concept unrelated to RTI; and Heat-Actuated Device describes the activation mechanism but does not specify the RTI value.