A dry pipe sprinkler system is charged with what?

A dry pipe sprinkler system is charged with what?

• A. Air
• B. Water
• C. Steam
• D. Nitrogen

Answer: (A)

A dry pipe sprinkler system uses pressurized air in the piping to keep it dry and prevent freezing, with water held back behind a dry pipe valve. When a sprinkler head is activated, the pressurized air is displaced, the valve releases, and water rushes into the piping to reach the sprinklers. This setup contrasts with wet systems, where water is already in the pipes. Using air (or an inert gas such as nitrogen) allows the system to stay dry and ready without filling with water until needed. While nitrogen can be used to reduce corrosion in some installations, air is the standard answer in most exam contexts.

A dry pipe sprinkler system uses pressurized air in the piping to keep it dry and prevent freezing, with water held back behind a dry pipe valve. When a sprinkler head is activated, the pressurized air is displaced, the valve releases, and water rushes into the piping to reach the sprinklers. This setup contrasts with wet systems, where water is already in the pipes. Using air (or an inert gas such as nitrogen) allows the system to stay dry and ready without filling with water until needed. While nitrogen can be used to reduce corrosion in some installations, air is the standard answer in most exam contexts.