A NAC extender in a protected premise fire alarm system is required to work normally at which humidity and temperature?

• A. 60% relative humidity and 70°F
• B. 85% humidity and 86°F
• C. 30% humidity and 32°F
• D. 100% humidity and 120°F

Answer: (B)

Electronic fire alarm components are built to operate in environments that are humid but not condensating and at moderate indoor temperatures. The NAC extender’s normal operating condition is about 85% relative humidity at 86°F (around 30°C). This reflects the upper limit of non-condensing humidity for electronics while staying within a typical indoor temperature range, ensuring reliable performance without moisture damage or overheating.

The other options push conditions outside what’s considered normal for protected-premises equipment: either the temperature is too cold or too hot, or humidity is at a level (100% RH) that would readily lead to condensation and potential malfunctions.