1.1 — Single line on tank water, without changeover

"The primary responsibility of the Engineer is the safe delivery of the personnel, apparatus and equipment to a reported fire or emergency and the delivery of water to the operating firefighting force." The listed responsibilities include maintaining the apparatus in a constant state of readiness, effectively operating any apparatus assigned, and "must know how many hose lines, size, length, nozzles, and the flow rates of their apparatus (per OFD hydraulic standard)."

"The Engineer must be thoroughly familiar with the engine apparatus, all the tools and equipment carried on board and the layout of the hose beds" — and "must control how many and what type streams and hose lines are supplied and should confer with and advise the officer when necessary."

In suppression the Engineer's tasks are listed as water supply, pump operations, and observing the conditions of all the hoselines stretched.

Engine Company Operations 2023 V-1, Firefighter Assignments, pp.1-8–1-9

"Using a 1 ¾" on a one to two room involved residential structure, an extended line (alley lay) on a garden style apartment, or a 2 ½" hoseline on a commercial building would be common examples of the occupancy dictating the line used."

Interior operations inside residential structures are "usually best accomplished with a minimum 150 gpm flow provided by 1 ¾" hoselines" — enough flow for multiple rooms of fire while keeping the speed and flexibility needed inside.

On commercial buildings the manual recommends 2½" because of the potential for large volumes of fire, and recommends a minimum of 100' of working line be stretched and flaked for use interior — the Nozzle Firefighter has to account for that additional 50' when estimating.

Engine Company Operations 2023 V-1, Firefighter Assignments, pp.1-12 and 1-14 · Stretching and Operating the Hoseline, p.4-2

For the "in between" fire — bigger than a 1¾" can handle, not clearly a 2½" job — the manual gives an acronym for when a 2½" hoseline is recommended:

• A — Advanced fire conditions on arrival.
• D — Defensive operations.
• U — Unable to determine seat or location of fire.
• L — Large, un-compartmentalized area (supermarket, bowling alley, warehouse).
• T — "Tons of water". Any time you need to deliver a large volume of water 250 gpm or more.
• S — Standpipe operations.

A middle option exists: a 1¾" line connected to 2½" hose and a shutoff. If conditions deteriorate the crew can back up, disconnect the 1¾", replace the 2½" nozzle and advance the 2½" already stretched.

Engine Company Operations 2023 V-1, Stretching and Operating the Hoseline, p.4-2

The Nozzle Firefighter is responsible for stretching the first hoseline to the point of entry, and in most situations for the first 100' of hose and the nozzle (lead length). Where the Back-Up Firefighter is performing other duties not associated with stretching — water supply, forced entry — the Nozzle Firefighter is responsible for stretching and flaking the entire hoseline.

In Investigation Mode the Nozzle Firefighter stands fast at the engine, size-ups the building, estimates the possible length of the stretch and determines the size of line that may be needed while the Officer and Back-Up Firefighter investigate.

Engine Company Operations 2023 V-1, Firefighter Assignments, pp.1-12–1-13

"Estimating the stretch can make or break the success of the initial attack line." The general guidelines given:

• The average width of a residential property plot is 50'.
• Front door to rear door of a typical residence is usually covered with 50'.
• An additional 50' per story may be necessary to reach a fire on the upper floors of a large residential dwelling.
• For commercial buildings, add the length and width of the building and use that number as the feet of 2½" needed.
• Break a long stretch down into 50' sections in your mind.

For large multiple dwellings the estimate must also carry the actual distance from the engine to the entrance door, the distance from that door to the base of the stairway, plus one length per floor and one for the fire floor — some buildings need two or more for the fire floor.

Engine Company Operations 2023 V-1, Stretching and Operating the Hoseline, pp.4-3–4-4

After the attack line is stretched, the Back-Up Firefighter makes sure the hose is properly flaked and kink free up to the lead length while the Nozzle Firefighter waits for water. Although the Nozzle Firefighter owns the lead length, the Back-Up Firefighter "should visualize and ensure that the entire line is kink free."

• One/Two Residential Dwelling and Garden Style Apartments: the hose is generally stretched, flaked and charged outside the structure before advancing inside. When possible it is good practice that the hose be flaked perpendicular to the point of entry — this lets the Back-Up Firefighter move hose inside more efficiently during the advancement.
• Multi-family dwelling with public hallways: the line can be flaked in the hallway on the fire floor before charging if conditions allow — apartment door intact, no fire in the hall, light smoke. "A good rule of thumb is if you are masking up, you should be calling for water."

Engine Company Operations 2023 V-1, Firefighter Assignments, p.1-25

Once the line is charged the Back-Up Firefighter's position is the door, feeding the line into the fire area — "slowly feeds line to the advancing nozzle team from their position at the doorway." Standing in the doorway itself blocks access, egress and ventilation.

"The Back-Up Firefighter must not push the hoseline to the nozzle team, but instead feed hose at the speed of the nozzle team so that the hoseline advances" — with the slack managed between the doorway and the nozzle.

Engine Company Operations 2023 V-1, Firefighter Assignments, p.1-26

ADO Task #19 is written for the changeover, but its first seven steps are this evolution — putting the pump in service on tank water before any external supply exists:

• Step 1 — Position the apparatus in a safe positon, and immobilize it by setting the parking brake and chocking the wheels.
• Step 2 — Engage the pump, and select the proper gear in the road transmission. Lock the gear into place.
• Step 3 — Open the tank-to-pump valve (if necessary).
• Step 4 — Set the transfer valve to the series (to PSI or RMP) positon depending on application.
• Step 5 — Increase the throttle setting to obtain the desired pressure, priming (if necessary).
• Step 6 — Set the relief valve or pressure governor.
• Step 7 — Open the circulator valve or partially open the tank fill valve.

Two placement differences against the printed evolution sheet, both open items rather than corrections: the pump skill opens the circulator/tank-fill valve after priming (Step 7) where the sheet cracks it at out-of-cab step 3, and it sets the relief valve at Step 6 where the sheet sets it at step 12.

ADO Task #19, Basic Pump Skills — Changeover (Transition to an External Water Supply), Operating Procedure