Ladder truck master stream: which option is the rated flow and pressure?

• A. 5000 LPM at 800 kPa
• B. 7000 LPM at 1000 kPa
• C. 3000 LPM at 900 kPa
• D. 10000 LPM at 700 kPa

Answer: (B)

Master streams on ladder trucks are specified with a rated flow at a standard nozzle pressure to give crews a predictable performance. For ladder truck master streams, the commonly published rating is 7,000 LPM at 1,000 kPa (about 145 psi), which works out to roughly 1,850 gpm. This specific combination reflects the level of flow the appliance can reliably deliver at a practical pressure, balancing reach and penetration for large fires. That’s why the option showing 7,000 LPM at 1,000 kPa is the rated flow and pressure. The other options don’t match this standard rating, even though they present plausible numbers; they don’t align with the typical ladder master stream specification.