What is an important characteristic of a fire hose?

A fire hose needs to be flexible under pressure to effectively deliver water to combat a fire. This characteristic is crucial because during operation, the hose experiences significant internal pressure from the water being pumped through it, as well as external forces such as being managed by firefighters, maneuvered around obstacles, and being laid out in various configurations. Flexibility allows the hose to bend and twist as needed without kinking or bursting, which could impede water flow and create safety hazards for the crew and the operation.

Other characteristics such as being lightweight, easily replaceable, or waterproof are certainly beneficial but do not address the primary function of maintaining an efficient and uninterrupted flow of water under pressure. Flexibility directly impacts the practical effectiveness and safety of the hose in real firefighting scenarios.