Ch13 Set 08: Fire Hose Operations

What hose sizes does the outline classify as small hoselines for operation?

Booster lines and 1½-, 1¾-, and 2-inch lines.

When may small lines require extra personnel?

When charged or when negotiating obstructions.

What small-line situations may use one firefighter in the outline?

Small ground-cover, rubbish, vehicle, shed or outbuilding fires, and rekindles during overhaul.

What is the minimum attack-line staffing for interior structural operations in the outline?

Two firefighters.

How does the nozzle operator hold a small line?

One hand on the nozzle, the other on hose behind it, with hose against the waist and across the hip.

Where and how does the backup firefighter support a small line?

On the same side about 3 feet behind, holding with both hands and bracing at the waist, hip, or leg.

How can prolonged small-line operations be made less tiring?

Use a hose strap or rope hose tool to help resist reaction.

What warning applies to directing water into ventilation openings during interior attack?

Do not direct fog into such openings; if a crew is immediately beyond an opening, do not direct any hose stream into it.

What hose sizes are addressed by large-attack-line operating methods?

2½- and 3-inch or larger attack hose.

When may one firefighter operate a large line according to the outline?

For exposure protection or overhaul when a master-stream device is unavailable.

How may one firefighter reduce fatigue on a large line?

Use a shoulder-looped hose strap or rope tool and reduce flow if conditions permit.

Why may two firefighters need to anchor a large line?

To offset nozzle reaction.

How does a large-line nozzle operator use a hose strap?

Loop it around the hose near the nozzle and across the back over the outside shoulder.

How does the backup firefighter anchor a large line?

About 3 feet behind, using a hose strap or rope tool and leaning the shoulder forward.

Why do different nozzles handle differently?

Design, pattern, setting, and operating pressure affect handling.

What is nozzle reaction?

The force opposite the outgoing water stream that pushes back against the nozzle operator.

What increases nozzle reaction?

Greater discharge pressure and flow, and the resulting water velocity.

How does the outline describe fog-pattern effects on nozzle reaction?

Straight and narrow fog resemble smooth-bore reaction; wider fog decreases reaction.

What kneeling position can be used to operate a nozzle inside?

Operating on one knee.

What hose sizes generally require additional personnel for handling?

1¾-inch or larger needs help with reaction and movement.

How do the basic handling methods for fog and smooth-bore nozzles compare?

The same basic handling methods apply.

What is friction loss?

Pressure lost as water moves through hose, pipes, fittings, and adapters.

What is a common example of friction loss?

Pressure loss between the pumper and nozzle.

How do hose diameter and lay length affect friction loss?

Smaller hose and longer lays increase loss at a given flow.

What hose conditions or fittings increase friction loss?

Rough linings, damaged couplings, sharp bends or kinks, and additional adapters.

How can friction loss be reduced or compensated for?

Use larger or parallel lines, remove kinks and sharp bends, or increase pump pressure.

How does nozzle elevation affect pressure?

Above the pump causes pressure loss; below it causes pressure gain.

What is water hammer?

A pressure surge or shock wave when moving water is abruptly stopped.

What can water hammer damage?

Water mains, plumbing, hose, hydrants, and pumps.

How does flow affect water hammer, and how is it prevented?

Higher flows increase its effects; close nozzles, hydrants, valves, and hose clamps slowly.