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Printable DO Pumper Instructor Packs

Ready-to-print practice sets with answer keys for pump pressure, wye operations, relay pumping, water supply, and practical station review.

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How to use these packs

Use these as station drills, academy review, or practical prep. Each pack includes original practice questions and an answer key. Adjust numbers to match your department hose, nozzles, SOPs, and local testing expectations.

PDP = NP + FL ± Elevation + Appliance Loss
FL per 100' = C × (GPM / 100)²

Pack 1

Basic Pump Pressure

Attack line pump pressure and friction loss practice.

1. 200' of 1¾" hose flows 185 GPM through a 50 psi fog nozzle. Use C=15.5. What PDP?

Answer: Q=1.85. FL/100=15.5×1.85²=53 psi. Two lengths = 106 psi. PDP=50+106=156 psi.

2. 150' of 1¾" hose flows 150 GPM through a 100 psi fog nozzle. Use C=15.5. What PDP?

Answer: Q=1.5. FL/100=15.5×2.25=35 psi. 1.5 lengths=52 psi. PDP=100+52=152 psi.

3. 300' of 2½" hose flows 250 GPM through a 50 psi smooth bore. Use C=2. What PDP?

Answer: Q=2.5. FL/100=2×6.25=12.5 psi. Three lengths=38 psi. PDP=50+38=88 psi.

4. Add 20 psi appliance loss to a line that otherwise needs 145 psi. What PDP?

Answer: 145+20=165 psi.

5. A nozzle is 30' above the pump. What elevation adjustment should be added?

Answer: 5 psi per 10' elevation gain. 30' = +15 psi.

Pack 2

Wye Operations

Branch-line calculations where the highest pressure branch governs.

1. A wye has Branch A needing 140 psi and Branch B needing 165 psi. What should the pump operator supply to the wye?

Answer: Use the highest required branch pressure. Supply the wye for 165 psi at the wye, then add main line friction loss and appliance loss if applicable.

2. Main line to a gated wye loses 30 psi. The highest branch requires 155 psi at the wye. Appliance loss is 10 psi. What PDP?

Answer: PDP=155+30+10=195 psi.

3. Why should the operator avoid averaging branch pressures?

Answer: Averaging under-pumps the higher-pressure branch. The branch needing the most pressure controls the operation.

4. What should be checked if one branch of a wye is weak?

Answer: Correct branch, kinks, valve position, nozzle setting, actual hose length, flow, and whether PDP was set for the highest-pressure branch.

Pack 3

Relay & Water Supply

LDH, relay spacing, tank duration, and water supply questions.

1. Why can 4" or 5" LDH move water farther than smaller attack hose?

Answer: Larger hose has much lower friction loss at the same flow, allowing longer lays and better residual pressure.

2. A 750-gallon tank is supplying 250 GPM. About how long until the tank is empty?

Answer: 750 ÷ 250 = 3 minutes, before accounting for safety margin or refill.

3. What signs suggest the water supply is not keeping up?

Answer: Dropping intake pressure, falling discharge pressure, cavitation, tank level dropping while on hydrant/relay, or reports of reduced nozzle stream.

4. What factors determine relay engine spacing?

Answer: Desired flow, hose diameter/C value, available discharge pressure, terrain/elevation, intake residual target, and department limits.

Pack 4

DO Pumper Practical Prep

Oral review and troubleshooting prompts for practical stations.

1. Before charging a line, what should the pump operator confirm?

Answer: Correct line, crew readiness, nozzle/appliance expectation, discharge closed or controlled, supply status, and communication method.

2. The crew reports poor stream after you set the calculated PDP. What is your first troubleshooting sequence?

Answer: Verify correct discharge, pressure, kinks, valves, nozzle setting, hose length, flow, and intake/supply pressure.

3. Why should pump changes be made smoothly?

Answer: Sudden pressure changes can create water hammer, move hose lines unexpectedly, and increase risk to crews.

4. What should be documented or reviewed after a training evolution?

Answer: Scenario setup, hose/nozzle package, target PDP, actual PDP, water supply, communication issues, and student performance notes.