If the maximum ceiling temperature is 170°F (77°C), which classification applies?

If the maximum ceiling temperature is 170°F (77°C), which classification applies?

• A. Ordinary
• B. Intermediate
• C. High
• D. Low

Answer: (A)

In NFPA 13R, ceiling temperature classification describes the heat level of the space above the sprinkler to guide what category of environment the installation is considered and to help select appropriate sprinkler and design assumptions. A maximum ceiling temperature of 170°F (77°C) falls into the Ordinary category, which covers typical indoor spaces where ceilings aren’t exposed to very high heat. If the ceiling temperature were higher than 170°F, the High category would apply; lower ranges correspond to Low or Intermediate depending on the exact temperature. So, the space with a ceiling temperature limit of 170°F is classified as Ordinary.

In NFPA 13R, ceiling temperature classification describes the heat level of the space above the sprinkler to guide what category of environment the installation is considered and to help select appropriate sprinkler and design assumptions. A maximum ceiling temperature of 170°F (77°C) falls into the Ordinary category, which covers typical indoor spaces where ceilings aren’t exposed to very high heat. If the ceiling temperature were higher than 170°F, the High category would apply; lower ranges correspond to Low or Intermediate depending on the exact temperature. So, the space with a ceiling temperature limit of 170°F is classified as Ordinary.