A drawback of wet pipe sprinkler systems is their susceptibility to what condition?

• A. Freezing
• B. Vibration
• C. Corrosion
• D. Overpressure

Answer: (A)

Wet pipe sprinkler systems have water-filled pipes that carry water to the sprinkler heads. In freezing conditions, that water can freeze. Ice expands and can crack pipes or fittings, create blockages, or cause leaks, which prevents water from reaching the heads when a fire occurs. This vulnerability to freezing is the main drawback of wet pipe systems in unheated or poorly heated spaces. To prevent it, these systems are avoided or protected with heating and insulation in cold environments, or a different type such as a dry pipe system is used. Vibration, corrosion, and overpressure are less central vulnerabilities for this particular system type.