1540 Ch 5 PowerPoint

1. Fire Protection Systems
Third Edition
Chapter 5 — Water Supplies for Fire Protection Systems

2. Objectives
‣ Define the terms pressure, flow, and duration as they relate to
the movement of water.
‣ Discuss the characteristics of the source/supply network and
the distribution network.
‣ Discuss the difference between a municipal/public water system
and a private water system.

3. Objectives
‣ Describe how pumped, gravity, and combined supply systems
operate.
‣ Define friction loss and discuss how it affects water flow.
‣ Identify and describe the components of a source/supply
network and distribution network.
‣ List and describe the different types of valves found in a
source/supply network and distribution network.

4. Objectives
‣ List and describe the different types of fire hydrants found in a
source/supply network and distribution network.
‣ Define the terms static pressure and residual pressure.
‣ List and discuss the characteristics of the two types of National
Fire Protection Association (NFPA)-approved stationary fire
pumps.
‣ Define the terms churn, total rated head, and peak load in
relation to stationary fire pump testing.

5. Introduction
‣ Water demand of a community changes throughout the day,
week, month, and year.
‣ Engineers need to determine if the source will meet community
needs, and if the delivery system is adequate.
‣ Fire flow models use various factors.
‣ Determining the adequacy of the water supply is one of the
most critical factors in designing a water-based fire protection
system.

6. Water Supply Systems
‣Source/supply network
‣Pumped system
‣Supply comes from deep well or surface source such as a
lake.
‣It is at a lower elevation than the location served and
requires a pump.
© A. Maurice Jones, Jr./Jones & Bartlett Learning

7. Water Supply Systems
‣Source/supply network
‣Gravity system
‣Supply is stored at
higher elevation
than the location
served.
‣Water flows at
sufficient pressure
on its own. © A. Maurice Jones, Jr./Jones & Bartlett Learning

8. Water Supply Systems
‣Source/supply network
‣Combined system uses both gravity and pumps.
© A. Maurice Jones, Jr./Jones & Bartlett Learning

9. Water Supply Systems
‣Distribution network
‣Transmission mains
‣Distribution mains
‣Service laterals/lines
‣For a distribution network to
be most effective,
transmission mains and
distributed mains are
connected together to form
loop and grid patterns.
© A. Maurice Jones, Jr./Jones & Bartlett Learning

10. Water Supply Systems
‣Distribution network
‣The branch or tree patterns in
a pipe configuration resembles
the trunk of a tree and
branches sprouting off of the
trunk.
‣The pipe configuration results
in dead-end water lines that
must receive regular service
and maintenance and ensure
water quality. © A. Maurice Jones, Jr./Jones & Bartlett Learning

11. Water Supply Systems
‣Fire lines and fire mains
‣Service laterals/lines that feed
water-based fire protection
systems
‣“FL” (fire line)
‣“FM” (fire main)
‣NFPA 24
‣The approving authority
engineer usually handles all
inspections, tests, and
certification of new public and
private water lines.
© A. Maurice Jones, Jr./Jones & Bartlett Learning

12. Water Supply Systems
‣ Water distribution system
valves
‣ Valves that control water
flow—public water systems
‣ Gate valves
© A. Maurice Jones, Jr./Jones & Bartlett Learning

13. Water Supply Systems
‣Water distribution system valves
‣Valves that control water flow—private water systems
‣Valves that control the direction of water flow
‣PIV
‣WPI
‣OSY

14. Fire Hydrants
‣ Overview
‣ Most important parts of any water
distribution network
‣ Support manual firefighting
operations
‣ Local building and fire codes
‣ Required location
‣ Number of hydrants in a
community
‣ Distance from hydrant to
hydrant
© Jones & Bartlett Learning.

15. Fire Hydrants
‣ Types of hydrants
‣ Dry barrel
‣ Wet barrel
‣ Water is in the barrel at all times.
‣ Wall, roof, flush, and yard

16. Fire Hydrants
‣Hydrant markings
‣NFPA making system hydrant
barrels in one color and the
caps and bonnet in a different
color
‣Expected water flow range
‣Public, private, nonpotable
hydrants
‣Locator flag attached to an
extension device or pole
provides a visual marker in
case of emergency.
© A. Maurice Jones, Jr./Jones & Bartlett Learning

17. Fire Hydrants
‣Hydrant inspection, testing, maintenance, and service
‣Tests for new hydrants similar to those for water lines
‣Need periodic testing/maintenance
‣Repainting, cleaning threads, lubricating the stems, caps,
plugs, and threads

18. Water Supply Design Considerations for
Water-Based Fire Protection Systems
‣Overview
‣Obtain pressure and flow readings from the water source
that will supply the system.
‣System’s supply evaluated for:
‣Adequacy
‣Flow pressure
‣Duration

19. Water Supply Design Considerations for
Water-Based Fire Protection Systems
‣Water flow test ensures water supply is adequate in:
‣Flow
‣Pressure
‣Duration
‣Fire hydrant flow tests are commonly used.
‣The system may need to be reevaluated.
‣Depending on the deficiency, different options are available.

20. Water Supply Design Considerations for
Water-Based Fire Protection Systems
‣Water pressurization
‣Static pressure
‣Residual pressure
‣Flow rate
‣Gravity
‣Pressure tanks

21. Water Supply Design Considerations for
Water-Based Fire Protection Systems
‣Stationary fire pumps
‣Fire pumps
‣Booster pumps
‣Special fire service pumps
‣Centrifugal pumps
‣Positive displacement
pumps
‣The flow and pressure reading
establishes the rated
performance.
‣Basis for pump’s
performance characteristics
© A. Maurice Jones, Jr./Jones & Bartlett Learning

22. Water Supply Design Considerations for
Water-Based Fire Protection Systems
‣Fire pump assembly components
‣Drivers
‣Controllers
‣Transfer switch
‣Jockey or pressure maintenance pump
‣Control valves

23. Water Supply Design Considerations for
Water-Based Fire Protection Systems
‣Fire pump assembly components (cont’d)
‣System relief valves
‣Bypass
‣Test headers and flowmeters
‣Gauges
‣Eccentric or concentric
reducers/increasers

24. Water Supply Design Considerations for
Water-Based Fire Protection Systems
‣Fire pump operation
‣Operates when there is sufficient loss of water pressure in
the system
‣Fire pump inspection, testing, maintenance, and service
‣Acceptance testing
‣Periodic inspection, testing, maintenance, and service