With the flow kept the same, which change lowers friction loss in a hose lay the most?
- Using hose of a smaller diameter
- Using hose of a larger diameter
- Adding more lengths to the hose lay
- Adding a gated wye in the line
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B. Using hose of a larger diameter
For the same flow, larger hose has far less friction loss because the water moves more slowly. Extra length and extra appliances both add friction loss.
Reference: Driver/operator: friction loss principles
In a forward lay, the hose is laid from the
- Fire to the water source
- Pumper to the nozzle team
- Water source to the fire
- Fire to a second pumper
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C. Water source to the fire
In a forward lay the engine stops at the hydrant, drops supply hose and lays toward the fire, so the pump ends up at the scene. Laying from the fire back to the source is a reverse lay.
Reference: Firefighter I: supply hose lays
After a reverse lay, where does the pumper that laid the hose end up?
- At the fire building
- Halfway between the two
- Back at the staging area
- At the water source
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D. At the water source
A reverse lay runs from the fire to the water source, so the pumper finishes at the hydrant or drafting site where it can pump the supply line. A pumper at the fire building is the result of a forward lay.
Reference: Firefighter I: supply hose lays