What is the fitting called where the fire department can hook up lines and flow water under pressure into a sprinkler system from the outside?

• A. FDC
• B. FD Connection
• C. Water Inlet
• D. Sprinkler Coupling

Answer: (A)

The fitting is the Fire Department Connection. It’s the exterior hookup firefighters use to pump water into a building’s sprinkler or standpipe system, providing a pressured water source from an outside pump or hydrant. The connection is designed to accept large hoses from the fire department and feed water directly into the system to boost pressure and flow during suppression. It’s typically a siamese setup with two large inlets (often 2.5 inches) and includes a check valve or backflow prevention to keep water from flowing back into the municipal supply. Other terms like Water Inlet or Sprinkler Coupling don’t specify this external, pressurized feed into the sprinkler system, so Fire Department Connection is the precise, standard term.