What is the water delivery device that flows a minimum of 350 gallons of water per minute called?

The water delivery device that flows a minimum of 350 gallons of water per minute is referred to as a master stream. This classification of water delivery is typically deployed in more significant fire situations or when tactical demands necessitate a high volume of water for effective suppression. Master streams are often used with onboard apparatus such as aerial ladders or ground monitors and are designed to effectively manage large-scale operations, delivering significant flow rates that are essential for extinguishing large fires.

In contrast, while large handlines can deliver substantial amounts of water, they generally do not achieve the flow rates associated with master streams. Meanwhile, a two-and-a-half refers to a specific hose diameter and can also deliver high volumes, yet it is still distinct from the master stream classification concerning the typical applications and flow rates. Lastly, a combination attack line is designed for versatility and usually operates at lower flow rates, typically tailored for use by a single firefighter or a small crew in more focused operations against smaller fires. Overall, the master stream is critical in firefighting for quickly addressing substantial fire incidents with its high flow capability.