Engine Operations›Engine Evolution
The main pumping evolution. Spot the rig, lock it down, get water on the line, take the hydrant without dropping the attack, and go big when it is called for. The steps are the muscle memory — tap a drop-down for what the manual says behind the step.
POSITION OUTSIDE COLLAPSE ZONE
If a stream has to go in front of a building it must be set back far enough that it will not be struck by falling walls or debris. The accepted figure is one and one-half times the height of the tallest exterior wall — a store front with a 20-foot wall gets a 30-foot zone, "the further the better."
Anyone working a stream from the front of the building is standing in that zone and may not have time to react to a sudden collapse of an exterior wall.
Engine Company Operations 2023 V-1, ch.7 Master Stream Operations, pp.7-1–7-2
UPHILL & UPWIND OF HAZARDS
LEAVE ROOM FOR AERIAL
"Generally, the first engine should leave the front of the building open for the Truck's aerial if needed." Getting the engine in close is a coordinated effort between the Engineer, the Engine Company Officer and the first arriving Truck.
Engine Company Operations 2023 V-1, p.1-9
The first Truck positions to cover side Alpha.
OFD Quick Reference Guide for Initial Company Operations, May 2024 · Initial company assignments
It runs the other way too — the ground ladders live on your rig. "On arrival in any apparatus, attention should be given to the location and accessibility of ground ladders." Parking tight to the ladder-rack side of an engine can block Outside Operations and Search from getting to them, and "it is recommended that Engineers be proactive in lowering ladder racks where applicable, for our Truck crews to access ground ladders faster." Ladder 33 needs a minimum of over 20 feet of clearance at the rear to pull its longest ladders.
OFD Truck Manual v3.1, §5, p.95 — Ladder-conscious positioning of apparatus
Spotting doctrine · Engine Company Operations, ch.1
GIVE THE OFFICER A LOOK AT THE BUILDING
Your first job on the brake is the officer's view.
"On arrival the Engineer of the first arriving engine needs to make every attempt to provide the Company Officer with a sufficient view of the fire building."
Engine Company Operations 2023 V-1, p.1-9
GET CLOSE — EVERY LENGTH COSTS TIME
Tight to the building so the stretch is short and the connection is quick.
"1st arriving Engine Company apparatus should be positioned as close as possible to the fire building to reduce the time, effort and number of lengths needed to connect to a water source. This tactic requires a coordinated effort between the Engineer, the Engine Company Officer, and the first arriving Truck Company for optimal placement."
Engine Company Operations 2023 V-1, p.1-9
SPOT FOR THE WATER YOU ARE GOING TO NEED
Supply, FDC, line placement, and where the fire actually is.
Other spotting considerations for the Engine Company: water supply needs · FDC connections · line placement · fire location and intensity.
Engine Company Operations 2023 V-1, p.1-9
And when you stretch off the rig: "The apparatus should be positioned so that it will not interfere with Truck Company operations."
Engine Company Operations 2023 V-1, p.1-11
POSITION FOR A FORWARD LAY WHENEVER SUPPLY IS COMING
Decide the lay while you are still rolling, not at the panel.
"The Engineer should position the apparatus for a Forward Lay whenever the need for water supply is determined. A hydrant in the immediate vicinity of the fire building may be used if it allows for a rapid stretch and will not interfere with ladder company positioning."
The first arriving Engine Company Officer makes the call on the need for water supply, or hands that responsibility to the second arriving engine — either way it is transmitted from first due to second due.
Engine Company Operations 2023 V-1, p.1-10
The three lays and the wet/dry choice are laid out in Water Supply.
NOTHING SHOWING — PARK WHERE A TRUCK STILL GETS IN
Alarms and investigations: pump in service, no hydrant yet, stay on the panel.
Engine Company Operations 2023 V-1, p.1-9
2ND DUE — DO NOT BLOCK, AND BE ABLE TO LAY
Your spot has to leave you able to put a supply line into the first-in engine.
"Second arriving engines should position so as not to block any apparatus movement on the fireground and be able to lay a supply line from the first-in engine to the hydrant."
Engine Company Operations 2023 V-1, p.1-9
"The Engineer of the second arriving engine is assigned to supply the first engine, this should be accomplished without placing their apparatus at the front of the fire scene. This is best accomplished by laying a supply line away from the first engine, spotting the second engine at the hydrant, connecting to that hydrant, and supplying the first arriving engine."
Engine Company Operations 2023 V-1, pp.1-10–1-11
3RD AND LATER — OUT OF THE WAY, OR TAKE THE ALLEY
Behind the structure buys easier additional lines.
"Third due engines and later-arriving engines should position their apparatus out of the way of the direct fire scene or consider taking a position in the alley behind the structure to provide additional lines more easily."
Engine Company Operations 2023 V-1, p.1-9
KNOW WHAT ARRIVAL ORDER MAKES YOU
The riding order sets the assignment before you ever pick a spot.
Residential and 1–3 floor multi-family: the 1st engine takes size-up and the 360 if not completed, stretches the initial attack line to the fire floor, and initiates water supply if the CO calls for it. The 2nd engine completes water supply, pumps the hydrant for the 1st engine if needed, and stretches the 2nd attack line. The 3rd stretches the back-up line to the 1st engine's location. The 4th stages at a second water supply and takes RIT.
Commercial moves the FDC to the 3rd engine — position on the FDC and pump it upon a "working fire".
OFD Quick Reference Guide for Initial Company Operations, May 2024 · full assignment grid
SET PARKING BRAKE
SET NEUTRAL
ENGAGE PUMP BUTTON
CHOCK WHEELS
Orem's changeover procedure opens on it: "Position the apparatus in a safe positon, and immobilize it by setting the parking brake and chocking the wheels." Step 2 is engaging the pump, selecting the proper gear in the road transmission, and locking the gear in place.
ADO Task #19, Basic Pump Skills — Changeover, operating procedure steps 1–2
On the drill ground the chock is out-of-cab step 6, right after prime.
ADO-Pumper task book, Evolutions 1.1–1.5 — out-of-cab step 6
OPEN TANK TO PUMP
OPEN TANK FILL / RECIRCULATION
PRIME PUMP (IF NECESSARY)
from Orem's evolutionsSET PSI CONTROL MODE BUTTON
Orem rigs: Engine 34 onlyCLEAR HOSE BED · BREAK ATTACK LINE (IF NECESSARY)
ADO-Pumper task book, Evolution 1.1 — out-of-cab steps 7–8
The Nozzle Firefighter owns the first 100 feet and the nozzle — the lead length. If the Back-Up Firefighter is pulled onto other duties — water supply, forced entry — then "the Nozzle Firefighter is responsible for stretching and flaking the entire hoseline." That is your cue that the stretch is going to take longer.
Engine Company Operations 2023 V-1, p.1-13
The Back-Up Firefighter's hose management is three things: chasing kinks · exterior management of the hose · supporting the movement of hose around corners and through doorways. "Failure of the Back-Up Firefighter to complete these tasks will lead to the delay in the initial attack line progressing to the seat of the fire."
Engine Company Operations 2023 V-1, p.1-17, restated p.1-21
And if a water supply is deemed necessary, the hydrant connection is the Back-Up Firefighter's responsibility — which is exactly when you lose him off the line.
Engine Company Operations 2023 V-1, p.1-21
On an extended lay into apartments, garden-style complexes or long-setback townhomes, the Back-Up Firefighter deploys the 1¾" Modified Minuteman to where it can be stretched near the point of entry, and the Nozzle Firefighter communicates the point of the attack line stretch.
Engine Company Operations 2023 V-1, p.1-14
CHARGE LINES
The line gets flaked at a safe area near the fire area — porch, stairway landing, hallway, adjoining area — and the Nozzle Firefighter finishes donning. When the line is flaked and he is ready he signals the Engineer to charge it. The signal may be verbal, by radio, or by hand signal.
He then bleeds trapped air with the nozzle fully opened and the stream directed away from the opening, and confirms pressure and pattern — a combination tip fully rotated to the straight stream position. "Right to Fight."
Engine Company Operations 2023 V-1, p.1-15
MARK OR NOTE DISCHARGE GAUGE & LINE LENGTH/LOCATION
from Orem's evolutionsCALCULATE PDP
"In order to establish and maintain proper pumping pressures, all Engineers must know how many hoselines, the size and length of the hoseline, the type of nozzles being used, and their flow." The manual also lists it as a standing responsibility — know how many hose lines, size, length, nozzles and flow rates on your apparatus, per the OFD hydraulic standard.
Engine Company Operations 2023 V-1, pp.1-8 and 1-11
"It is imperative that the Engineer listen closely to the radio at all times for traffic concerning charging, shutting down or adjusting hose line pressures." And monitor the residual pressure on the master intake gauge — that is what tells you whether you can supply additional volumes.
Engine Company Operations 2023 V-1, p.1-11
The Engineer "must control how many and what type streams and hose lines are supplied and should confer with and advise the officer when necessary."
Engine Company Operations 2023 V-1, p.1-8
SET PDP
SET DISCHARGE RELIEF VALVE
Manual valve: Engine 31 · Engine 3820 · Ladder 32The changeover procedure sets the relief valve or pressure governor at step 6 — before the external supply is introduced and before pressure is put to the line.
ADO Task #19, Basic Pump Skills — Changeover, operating procedure step 6
The drill-ground evolutions print the manual discharge relief valve as their last out-of-cab item. Set it early — see the field notes at the bottom of this sheet.
SET DISCHARGE RELIEF VALVE TO ~150
"…then when I introduce hydrant water there isn't as much of a pressure spike and the discharge relief valve will catch any extra. Then after hydrant is fully opened I can throttle back down."
Jason, 2026-08-30
THROTTLE UP TO 150 PSI
GATE DOWN HANDLINES TO THEIR SET PDP
CONNECT LDH SUPPLY
Orem uses three supply line lays — Forward (lay-in) · Reverse (lay-out) · Split — chosen on arrival order, direction of travel, occupancy type and anticipated water needs, and each can run wet or dry. Whatever the first-in Officer selects, "they MUST announce over the radio their water supply intentions so that the second due engine can adjust their strategies."
Engine Company Operations 2023 V-1, p.5-1
Wet lead: the Back-Up Firefighter stays at the hydrant and charges the line when told. Dry lead: the Tailboard Firefighter anchors the hose, leaves the hydrant bucket, and goes to the fire with the crew — someone else is assigned to charge it.
Engine Company Operations 2023 V-1, p.5-8
Reverse lay splits two ways: a supply evolution (LDH between the suction side of the pump and the hydrant) or an attack evolution (LDH off the discharge side to an appliance or master stream). Split lay is for when the first due has to park where there is no water — cul-de-sac, limited-access complex — dropping LDH at the entrance for the second due to complete. The first due must transmit the intention to split.
Engine Company Operations 2023 V-1, pp.5-9–5-11
"When performing a Forward Lay, the connection shall be made using 5" LDH, in the event the 5" LDH connection cannot be secured on the hydrant a minimum of 2-3" hoses shall be connected, one on each side of the hydrant. Pony lines are acceptable where connections are short as long as '5" LDH first' rules are applied."
Engine Company Operations 2023 V-1, p.1-11 · more in Water Supply
A single 5-inch line may not flow all of the available water from a hydrant or main. Provide one 5-inch hose line for every 1,000 gpm to be delivered.
A double 2½" hydrant — two 2½" outlets, no steamer — is fed by a 4" main; expect less than 600 gpm.
Engine Company Operations 2023 V-1, pp.5-4–5-5
To pull more out of the distribution system, least to best preferred: multiple supply lines from a single hydrant · pumping the hydrant with the 2nd or 3rd due engine supplying the attack pumper · multiple supply lines from different hydrants sharing the same water main · multiple supply lines from different hydrants not sharing the same main.
Engine Company Operations 2023 V-1, p.5-13 — High-Flow Hydrant Operations · relay spacing and pressures in Relay Pumping
OPEN PRESSURE RELIEF VALVE
SIGNAL FOR WATER
Orem's hydrants are dry-barrel. Once a dry-barrel hydrant is charged, no additional lines may be added to the other outlets unless the hydrant is shut down or a shut-off valve was added before charging. Opening the stem valve supplies ALL outlets at the same time — so multi-outlet dry barrels must have a 2½" gate valve attached to an unused outlet at the onset of any hydrant operation.
Stem valves open counter-clockwise — "open-left" — across every district around Orem.
Engine Company Operations 2023 V-1, pp.5-2 and 5-5
The hydrant bucket carries what the connection needs: screw-handle hydrant wrench, 5" Storz × 2½" female, 2½" and Storz spanners, two 2½" hydrant gate valves, a 2½" double-female for a 3" supply line, and a rubber mallet for stuck caps. Depending on the lay, the 1st or 2nd due engine leaves it at the hydrant.
Engine Company Operations 2023 V-1, p.5-6
Orem's own hydrant sequence: stretch LDH with the gate valve and hydrant bag · connect LDH to the steamer port and attach both gate valves to the 2½" outlets · flush the hydrant · open the hydrant slowly until the hose is charged · close the intake bleeder valve · open the intake valve · close tank to pump · mark or note the intake gauge · open tank fill to refill or confirm the tank is full · verbalize supply is established.
ADO-Pumper task book, Evolution 1.0 — out-of-cab hydrant/water supply steps 4–13
CLOSE PRESSURE RELIEF VALVE
OPEN SUPPLY INTAKE SLOWLY (MONITOR GAUGES)
Purge the air first. Air sitting in an empty supply hose causes problems if it enters the pump while the pump is supplying attack lines under pressure. Open the bleeder valve on the gated intake so the air escapes as the line fills; when all the air has been forced out, close the bleeder. The water is now at the pump and ready for the transition.
Then the transition. "The operator opens the intake valve from the supply line very slowly while observing the pressure on the intake and discharge gauges." Keep opening the intake and adjusting the discharge pressure until the intake is completely open — it may take throttle to hold the discharge pressure you want.
Then close tank-to-pump. After the intake valve is open the tank-to-pump valve can be closed — but leave the tank fill partially open until the tank has refilled. "A full tank provides a limited reserve water supply in the event that the external water supply is lost unexpectedly."
ADO Task #19, Basic Pump Skills — Changeover (Transition to an External Water Supply)
On the drill ground the standard is that the changeover has minimal impact on the hand lines — approximately 10 psi or less.
ADO-Pumper task book, Evolution 1.2 — objective note 2
THROTTLE BACK DOWN (ONCE HYDRANT IS FULLY OPEN)
CLOSE TANK TO PUMP
REFILL TANK
"As soon as an adequate supply of water is available, divert enough of it through the tank-fill line to replenish the supply in the tank." The full tank is your reserve if the external supply is lost unexpectedly.
ADO Task #19, Basic Pump Skills — Changeover, operating procedure step 8
*NOTE STATIC HYDRANT PRESSURE*
It is the number every like-volume call on this sheet works off.
PROPERLY SECURE DEVICE
Master streams generally mean interior offensive operations have been abandoned for a defensive posture. Once the line is in operation the device must be shut down to be repositioned — so the position has to be right the first time.
The safest exterior positions are the corners of the building. Setting up in front, whether off the top of the engine or off the ground, "is a dangerous and ineffective tactic" — the crew is in the collapse zone.
Two more things the higher flow does to you: it is more likely to knock debris loose from the building and throw it at people and apparatus; and in portable mode the device has a limited side-to-side range — turning the nozzle too far left or right can make the base unstable and tip it over.
Engine Company Operations 2023 V-1, ch.7, p.7-1
The Stinger is a break-apart monitor that works as a deck gun or as a portable — plumbed to an outlet on top of the engine so it goes into operation without running a supply line, or pulled off and dropped onto its base, which has folding legs and a single 5" LDH inlet and stows in the rear compartment. Going portable is how you get the fire away from the apparatus.
Engine Company Operations 2023 V-1, pp.7-4–7-5 · Master Streams
CALCULATE PDP
SET PDP
NOTIFY COMMAND OF BIG WATER
"Master stream operations require a coordinated effort from the companies operating on scene, one of which is ensuring that all department members have been backed out of the building prior to flowing any master stream or elevated ladder pipe."
By most definitions any stream greater than 350 gpm that requires mechanical assistance to handle is a master stream — portable, elevated, or mounted on the apparatus.
Engine Company Operations 2023 V-1, ch.7, p.7-1
STOP
Affirmative acknowledgement, not a one-way notification. A master stream must be shut down to be repositioned — the safest positions are the building corners; the front is dangerous, ineffective, and inside the collapse zone.
Engine Company Operations 2023 V-1, ch.7 Master Stream Operations, p.7-1OPEN DISCHARGE
A deck gun nozzle sitting nine to ten feet above the ground loses a lot of effectiveness at low angles. On a narrow street most of the water is wasted — the stream hits the floor only 25 to 30 feet inside the structure.
The most effective use of the pre-connected deck gun is a quick application of high-pressure water through the window to knock down heavy fire while other members get a handline into position by whatever means available. Faster fire control means increased life safety for civilians and firefighters.
At upper-floor angles the stream is less likely to push fire through the compartment and out into the hallway — most of the water strikes the ceiling and coarse droplets rain down on the burning contents. A smaller tip than normally used, and limiting the application, reduces that risk further; a 1½" tip generates the high velocity needed for reach and conserves water.
Engine Company Operations 2023 V-1, ch.7, pp.7-2–7-3
TURN ON FOAM
Field method. Hydrocarbons: area ÷ 20. Polar solvents / alcohols: area ÷ 5. That gives gallons of concentrate.
Full formula. Area × Critical Application Rate × Eduction Rate × 15 minutes = concentrate needed. CAR is 0.1 gpm/sq ft for hydrocarbons, 0.2 for polars. The eduction rate — the minimum metering valve setting — is 1–3% for hydrocarbons, 3–6% for polars. The 15 minutes is the NFPA 11 standard for concentrate on hand.
Worked example. A 10' × 10' gasoline spill: 100 × 0.1 × 0.03 × 15 = 4.5 gallons. Field method: 100 ÷ 20 = 5 gallons.
In-line eductors. Rated at 95 gpm — the eductor and the nozzle must have matching flow rates or the concentrate will not pick up. Designed for a 200 psi inlet. Do not exceed 70% back pressure beyond the eductor.
OFD Hydraulic Standard — Foam Operations §1–2
Maintain 20 PSI intake pressure
20 psi minimum protects from drawing a vacuum on the intake hose.
NOTIFY COMMAND
OPEN TANK TO PUMP
PRIMER
CHECK GAUGES
CHECK CONNECTIONS AIR TIGHT
CHECK HOSE FOR KINKS
CHECK HYDRANT
WORK BACKWARDS TO CAB
USE 1ST DIGIT METHOD TO DETERMINE ADDITIONAL LIKE VOLUMES REMAINING.
First digit of the intake pressure × 1, × 2, × 3. Compare the residual drop against those three numbers.
Table scrolls sideways →
| Multiple | Residual drop | Like volumes left |
|---|---|---|
| 90 × 1 = 9 | 1–9 psi | 3 |
| 90 × 2 = 18 | 10–18 psi | 2 |
| 90 × 3 = 27 | 19–27 psi | 1 |
| — | 28+ psi | 0 |
Related: net pump discharge pressure off a positive supply is PDP − intake psi. A 150 psi PDP on a 90 psi intake is 60 psi of actual work by the pump.
OFD Hydraulic Standard §3–4
Evolution 1.0 has no chock step.
Orem's Evolution 1.0 skill sheet runs its out-of-cab list from "verify pump is engaged" straight into the hydrant work — no wheel chocks anywhere in it. Evolutions 1.1 through 1.5 all carry "Set wheel chocks" as out-of-cab step 6, and ADO Task #19 opens by immobilising the rig with the parking brake and the chocks. The step belongs on 1.0 too. Committee item.
ADO-Pumper task book, Evolutions 1.0–1.5 · ADO Task #19 step 1
The relief valve is printed last, and set early.
The drill-ground evolutions list the manual discharge relief valve as the final out-of-cab item. ADO Task #19 sets the relief valve or pressure governor at step 6 — before the external supply is introduced. This sheet follows #19: set it before pressure reaches the line.
ADO Task #19 step 6 · ADO-Pumper task book, Evolution 1.1 out-of-cab step 12
Source. Engine evolution card, transcribed 2026-08-28 — wording, order and groupings as written, caps as printed. Orem's evolution material is layered in where tagged (ADO-Pumper task book · ADO Task #19); the Positioning doctrine is from Engine Company Operations chapter 1, with the Truck Manual and the Quick Reference Guide where they touch spotting; the relief-valve pre-set steps in Establish Supply and the master-stream order are per my 2026-08-30 review.
Version: prototype · Last reviewed 2026-08-30 · Compiled by Engineer Jason Anderson