How many GPM can a single 5-inch supply hose deliver when pumped by a key pumper?

The correct answer reflects the expected performance of a single 5-inch supply hose when utilized with a key pumper. The operational dynamics of fireground hydraulics indicate that a 5-inch hose can typically deliver a substantial flow of water due to its larger diameter compared to smaller hoses. When a proper pumping strategy is employed, including appropriate pump pressure and no excessive friction loss in the supply line, the delivery capacity can reach into the range of 1,800 to 1,900 gallons per minute (GPM).

This range is based on factors such as the capabilities of the key pumper, which is designed to handle higher flows, and the effective use of hose lines in firefighting operations. It’s essential to understand that flow rates can vary based on specific conditions, including length of hose, elevation changes, and the specific configuration of the firefighting operation, but the standardized expectations for a 5-inch hose in optimal conditions typically fall into this higher range. Understanding these parameters is crucial for effective water supply management during fire incidents.