Air is removed rapidly from a dry pipe system by?

• A. A vacuum breaker
• B. An accelerator and/or an exhauster
• C. A gate valve
• D. A pressure relief valve

Answer: (B)

In a dry pipe system, air in the piping must be removed quickly so that water can reach the sprinkler heads without delay. An accelerator and/or an exhauster are designed to vent or actively pull out that air, speeding up the filling of the system when water is released into the dry pipe main. The accelerator provides a controlled vent path for the trapped air, while an exhauster uses a fan or pump to actively remove air from the lines. By clearing the air fast, water can circulate through the system sooner, delivering rapid fire protection. A vacuum breaker, gate valve, and pressure relief valve do not perform this air-evacuation function.