Fire sprinkler systems consist of pipes, sprinkler heads, and water supply connections designed to automatically detect and suppress fires. The system is divided into zones with separate control valves allowing isolation for maintenance. Main water supply connects to the building and is sized to provide adequate volume and pressure. For buildings without adequate water pressure from the municipal water system, a pressure tank or pump is installed to boost pressure. Pipe routing follows a main riser from the water supply to branch lines serving sprinkler heads. Piping is typically steel in wet pipe systems (always filled with water) and may be plastic in dry pipe systems (charged with pressurized air). Pipe sizing is calculated based on water demand (gallons per minute) required by the number of heads that could activate. Most residential systems are designed for 4 to 8 heads operating simultaneously. Sprinkler heads are spaced according to their listing; typically 8 to 12 feet apart depending on the type. Standard spray heads cover an approximate 12-foot radius. Pendent heads hang from the ceiling; upright heads mount on top of pipes. The system includes a flow indicator (water-flow switch) that triggers an alarm when water flows, indicating activation. A pressure gauge at the main riser indicates system pressure. Drain valves allow system drainage for maintenance. Inspections and testing verify proper operation before occupancy. Flow testing ensures adequate water pressure and volume. Pressure testing of the pipe system ensures no leaks. Annual inspections are required by most codes; includes checking heads for damage, obstruction, and corrosion.