Which standpipe system type is listed as automatic and dry?

Which standpipe system type is listed as automatic and dry?

• A. Manual dry
• B. Wet standpipe
• C. Automatic wet
• D. Automatic dry

Answer: (D)

Standpipe systems are described by whether their piping is filled with water and whether water is delivered automatically. A dry standpipe keeps the piping empty of water, using air or another gas until needed. When a fire triggers the system, an automatic control valve charges the dry piping with water so outlets can deliver it without someone manually opening a valve. This combination—pipes that are dry until activated and that fill automatically when needed—is what “automatic dry” describes. If the system were manual dry, a person would have to open a valve to charge the lines. If it were wet, the pipes would be full of water at all times. If it were automatic wet, water would be in the pipes automatically, but not dry.

Standpipe systems are described by whether their piping is filled with water and whether water is delivered automatically. A dry standpipe keeps the piping empty of water, using air or another gas until needed. When a fire triggers the system, an automatic control valve charges the dry piping with water so outlets can deliver it without someone manually opening a valve. This combination—pipes that are dry until activated and that fill automatically when needed—is what “automatic dry” describes. If the system were manual dry, a person would have to open a valve to charge the lines. If it were wet, the pipes would be full of water at all times. If it were automatic wet, water would be in the pipes automatically, but not dry.