Chapter 10 - Pump Operations from Static Water Supply

Drafting from a static water source requires the D/O to understand:

Basic principles of lift

For each 1000ft (300m) of altitude gain, atmospheric pressure drops by:

0.5 psi (7 kPa)

While drafting, a reading at or close to ___ on the compound gauge indicates the pump as reached supply capacity

22 in Hg (-75 kPa)

The theoretical lift for a fire pumper drafting from a static source at sea level is:

33.8 ft (10 m)

In the fire service, ___ means the greatest height at which any amount of water may be raised through an intake hose to the pump

Maximum lift

The height of a column of water being lifted to provide a reliable fire flow is known as:

Dependable lift

When working with a dry hydrant, pumpers may:

Maintain a safer distance from the water’s edge

In order to use static water supplies located a modest distance from the apparatus, some jurisdictions employ:

An eductor

A safe and efficient manner for fire department tender shuttles to arrive, stage, fill, and depart is a route that:

Is circular

The minimum water depth when drafting with a barrel-type strainer is generally considered to be:

2ft (600 m)

If the D/O cannot establish an adequate draft due to clogging at the strainer, ___ with tank water may dislodge the debris

Back flushing

When using both portable and nonportable water sources, the D/O must avoid:

Cross-connections

When using a swimming pool as a static water source, consideration must be given for:

Access for the fire apparatus

Calculate the volume of a swimming pool that is 40ft (12m) wide, 100ft (30m) long, and has an average depth of 6ft (2m)

C = 1000 x L x W x D

180 000 gal (720 000 L)

Calculate the volume capacity of a swimming pool with a diameter of 24ft (8m) and an average depth of 4ft (1.3m)

C = 1000 × 3.14 x R² x D

13 565 gal (65 312 L)

Cavitation in a pump can be described as water:

Being discharged faster than it comes into the pump

To avoid pump cavitation, keep discharged rates lower than the:

Intake pressure

An appliance of choice when using a portable tank or swimming pool for drafting is the:

Low-level strainer

The ability of the pump to reach capacity is affected if the water temperature is below:

35^oF (1.7^oC)

The ability of the pump to reach capacity is affect if the water temperature is above:

90^oF (32^oC)

While priming the pump for drafting, the master intake gauge should indicate the following for each 1ft (300mm) of lift:

1 in Hg (-3.5 kPa)

When drafting, vacuum measurements come from the difference of pressure at the surface of the water and the:

Eye of the pump’s impeller

NFPA 1900 allows priming of the fire pumps up to 1250 gpm (5000 L/min) to accomplish a draft in up to:

30 seconds

If the D/O notices a gradual increase in vacuum with no change in flow during drafting, this indicates:

A developing blockage