Chapter 11- Operating Fire Pumps

Question 0

If it is necessary, can you drop below the recommended minimum intake pressure level? What is that level?

Answer 0

Yes, if necessary you can drop below 20 psi, but you shouldn’t drop to zero.

Question 1

To avoid possible damage to the water system, the intake pressure should not drop below _____psi?

Answer 1

20 psi

Question 2

Types of hydrants: Class, Color, Flow

Answer 2

AA. Light Blue. 1500 or greater
A. Green. 1000 to 1499
B. Orange. 500 to 999
C. Red. Below 500

Question 3

What is the definition of static pressure?

Answer 3

When a pumper is connected to a hydrant and is not discharging water. That pressure is static pressure.

Question 4

What is the definition of residual pressure?

Answer 4

When the pumper is discharging water, the intake reading is the residual pressure.

Question 5

How do you determine how much more water the hydrant can supply?

Answer 5

The difference between the static pressure and the residual pressure is used. There are three methods.

1. Percentage method
2. First digit method
3. Squaring the lines method

Question 6

One foot of lift equals ??? Inches of Mercury?

Answer 6

One foot of lift equals 0.885 inches Mercury

Question 7

Maximum theoretical lift is?

Answer 7

33.8 feet

Question 8

Relationship between atmospheric pressure and psi?

Answer 8

Atmospheric pressure drops .5 psi per 1000 feet

Question 9

What is the required vacuum for the primer?

Answer 9

22 inches of Mercury