Which sprinkler head type is commonly associated with glass bulbs that break at a specified temperature?

Which sprinkler head type is commonly associated with glass bulbs that break at a specified temperature?

• A. Thermally Activated Cap
• B. Electronic Sensor Head
• C. Glass Bulb Sprinkler Head
• D. Fusible Link Head

Answer: (C)

Sprinkler heads are activated by temperature-sensitive mechanisms that release water when heat is detected. The type that uses a glass bulb is designed so a tiny glass capsule filled with a heat-sensitive liquid will break at a specific temperature. When the surrounding heat reaches that rated temperature, the liquid expands or pressure changes inside the bulb until it shatters, freeing the valve stem and allowing water to flow through the head. This provides a precise, predictable activation temperature based on the bulb’s rating. Other designs rely on different mechanisms—such as a fusible metal link that melts at a set temperature or electronic sensors that trigger from external inputs—so they do not involve a glass bulb that breaks.

Sprinkler heads are activated by temperature-sensitive mechanisms that release water when heat is detected. The type that uses a glass bulb is designed so a tiny glass capsule filled with a heat-sensitive liquid will break at a specific temperature. When the surrounding heat reaches that rated temperature, the liquid expands or pressure changes inside the bulb until it shatters, freeing the valve stem and allowing water to flow through the head. This provides a precise, predictable activation temperature based on the bulb’s rating. Other designs rely on different mechanisms—such as a fusible metal link that melts at a set temperature or electronic sensors that trigger from external inputs—so they do not involve a glass bulb that breaks.