Friction loss per 100 ft is used in calculations to estimate total friction loss by multiplying by hose length in hundreds of feet.

• A. It is a chart value representing pressure loss for 100 ft of hose at a given GPM; multiply by total length in hundreds of feet to estimate total FL.
• B. It measures the water temperature.
• C. It is the noise level in the hose.
• D. It is unrelated to GPM.

Answer: (A)

Friction loss per 100 ft is a charted pressure drop for a specific flow rate through a given hose size. Because the pressure drop through hose scales with length, you treat this value as a unit (per 100 ft) and multiply by the total length expressed in hundreds of feet to estimate the total friction loss. For example, if the chart shows 25 psi friction loss per 100 ft at the operating GPM, and the hose length is 600 ft, you multiply 25 by 6 (since 600 ft is 6 hundreds of feet) to get about 150 psi total friction loss. This approach hinges on the actual flow rate because the per-100-ft value changes with GPM, hose diameter, and hose roughness, which is why the chart is used specifically for the given GPM.

Temperature and noise levels aren’t what this friction loss value measures, and friction loss is directly tied to the flow rate (GPM), so it isn’t unrelated to GPM.