Which device operates automatically when heated to a thermal rating?

Which device operates automatically when heated to a thermal rating?

• A. Compartment
• B. Heat-Actuated Device
• C. Dwelling Unit
• D. Quick-Response (QR) Sprinkler

Answer: (B)

Heat-activated devices are designed to operate automatically when the ambient temperature reaches their rated heat value. In a sprinkler system, a sprinkler head is a heat-activated device—the heat-sensitive element holds it in place, and when the temperature hits the rated level, the element releases so water can discharge. The other terms don’t describe a device that automatically actuates from heat: a compartment or a dwelling unit are building/space terms, not actuating components, and a Quick-Response sprinkler is a specific type of sprinkler that happens to be heat-activated, but the general category described by the phrase is heat-activated device.

Heat-activated devices are designed to operate automatically when the ambient temperature reaches their rated heat value. In a sprinkler system, a sprinkler head is a heat-activated device—the heat-sensitive element holds it in place, and when the temperature hits the rated level, the element releases so water can discharge. The other terms don’t describe a device that automatically actuates from heat: a compartment or a dwelling unit are building/space terms, not actuating components, and a Quick-Response sprinkler is a specific type of sprinkler that happens to be heat-activated, but the general category described by the phrase is heat-activated device.