What temperature rating is required for heat detectors used with the elevator sprinkler arrangement?

• A. Higher temperature rating
• B. Lower temperature rating
• C. Same temperature rating
• D. Variable rating

Answer: (B)

Heat detectors in an elevator sprinkler arrangement are meant to trigger the water supply to the hoistway quickly when heat is detected. Because the elevator shaft is a confined space where rapid flooding is crucial for protecting the car and equipment, these detectors are chosen with a lower temperature rating than the sprinkler heads in the same system. A lower rating ensures the detectors trip at a lower heat level, initiating water flow before the heat reaches the sprinkler heads and helping to control the fire sooner. Using a higher rating would delay activation, while a same rating provides less margin for reliable operation and a variable rating would create inconsistency. So, a lower temperature rating is required.