1. QA September 2001 Fire Topic
Fire Stream Practices

2. Fire Extinguishment Theory
Temperature Reduction: usually by applying water
Fuel Removal:
stop fuel from being added
remove fuel from path of fire
Oxygen Exclusion or Dilution
introduce inert gas: carbon dioxide, nitrogen
separate or smother: steam, foam
Inhibiting Chemical Reaction
Dry chemicals, halons, etc. interrupt flame production.
most effective on liquid and gas fuels

3. Compatibility
Determine the extinguishing method or extinguishing agent compatible with the material involved.

4. Characteristics of Water
Molecule of two parts hydrogen and one part oxygen
Solid 32 degrees (freezing point)
Liquid 32 to 212 degrees (boiling point)
Gas (water vapor or > 212 degrees
Practically incompressible
Weight: approximately 62.5 lb/ft3
Absorbs large amounts of heat by 2 laws of physics:
Law of specific heat: heat-absorbing capacity of a substance (water is given a value of 1.00)
Latent Heat of Vaporization: heat absorbed during vaporization

5. Advantages of Water as Agent
Great heat absorption capacity
Readily available
Inexpensive
1,700:1 vaporization expansion ratio

6. Disadvantages of Water
High surface tension
Reactivity with certain materials
Can freeze
Low viscosity
Electrically conductive
Heavy

7. 6 Principles of Pressure
Fluid pressure is perpendicular to any surface.
Fluid pressure at a point in a fluid at rest is the same intensity in all directions.
Pressure applied to a confined liquid from without is transmitted equally in all directions.
The pressure of a liquid in an open vessel is proportional to its depth.

8. 6 Principles of Pressure (cont.)
The pressure of a liquid in an open vessel is relative to its density
The shape of a vessel is irrelevant to the pressure of the liquid.

9. Types of Pressure
Atmospheric: the pressure applied to the surface by the Earth’s atmosphere (14.7 sea level)
Head: height of a water supply above discharge
Static: pressure in a water system before water flows from a hydrant
Normal Operating: pressure in water distribution system during normal consumption demands
Residual: pressure remaining after overcoming gravity and friction loss when forcing water through pipe, fittings, fire hose, and appliances

10. Types of Pressure (cont)
Flow / Velocity: forward force pressure at a discharge opening while flowing water
Elevation Loss and Gain:
nozzle above pump = pressure loss
nozzle below pump = pressure gain
0.434 psi per foot

11. Principles of Friction Loss
Friction Loss: portion of total pressure lost while forcing water through pipe, fittings, fire hose, etc.
varies with length of hose
varies with velocity (if flow doubles, FL quadruples)
varies with hose diameter
FL same, regardless of pressure
Critical Velocity: turbulent agitation created when velocity limits are exceeded
Water Hammer: damaging energy surge created when water is suddenly stopped

12. Fire Stream: a stream of water or water-based extinguishing agent from the time it leaves the nozzle until it reaches the desired point.
The condition and effectiveness of the stream is influenced by:
design, adjustment, and condition of the nozzle
operating pressure
velocity
gravity
wind
friction with the air

13. Fire Stream Production 4 basic elements:
Water Supply
Static Supply: lakes, rivers, swimming pools, portable tanks, etc. (Where are the drafting locations in your run districts?)
Apparatus Water Tanks (What is the capacity of your booster tank?)
Pressurized Distribution System (Do you know the hydrant capacity color-coding system?)

14. Fire Stream Production 4 basic elements: (cont.)
Fire Department Pumper: receives water supply and increases pressure to required level for an effective production of fire streams (What is the rated capacity of your engine?)

15. Fire Stream Production 4 basic elements: (cont.)
Fire Equipment
Hose (What sizes and lengths are on your engine?)
Nozzles: forms and shapes the stream
Appliances: wyes, siameses, manifolds, double couplings, water thieves, etc.
Hardware: spanner wrenches, hose straps, hose bridges, etc.

16. Fire Stream Production 4 basic elements: (cont.)
Trained Personnel: The best supply, apparatus, and equipment will not produce effective fire streams without well trained personnel.

17. Sizes & Types of Fire Streams Fire Streams are identified by size and type.
Size: stream volume in gallons per minute (GPM)
Handline: 40 GPM to 350 GPM
Master Stream: >350 GPM
Type: stream shape or pattern
Solid: Produced by a smoothbore, fixed-orifice nozzle (long range/ high volume). The stream must maintain continuity, must shoot 9/10ths through a 15” circle and 3/4ths through a 10” circle, must attain height in moderate wind.

18. Types of Fire Streams (cont.)
Solid (cont.): The flow rate and the reach depend upon the velocity (discharge pressure) and the diameter of the nozzle orifice. At equal pressure, doubling the nozzle size will quadruple the GPM. The maximum horizontal reach is achieved at 32 degrees. The optimum vertical reach is at 70 to 75 degrees.
Fog Stream: varied pattern stream, composed of water droplets/ from wide (45-80 degrees), to narrow (15-45 degrees), to straight.

19. Types of Fire Streams (cont.)
Broken Streams
produced by special stream nozzles (water curtains, rotary distributor, spoon billed, etc.) or by directing two solid streams together
do not have a specific pattern
composed of large drops
usually not adjustable
for fires in attics, basements, partitions, etc.
increased water damage should be expected

20. Types of Nozzles Solid Stream Nozzles Fog Stream Nozzles
Handline Nozzles
Master Stream Nozzles
Special Purpose Nozzles

21. Foam Fire Streams
Foam concentrate is added to a water fire stream using a proportioning device, which creates a foam solution
Air is added to the solution, which creates the finished foam
Effective on flammable liquids, hazardous materials spills, confined space fires, bulk class A fires

22. Foam Fire Stream Production
1. Choose appropriate foam concentrate
2. Use hydraulically compatible eductor and nozzle
3. Set eductor to proper concentration percentage
4. Attach eductor, attack hose, and nozzle to pump
5. Assemble sufficient foam concentrate at eductor
6. Place eductor suction hose in concentrate
7. Increase water pressure to eductor specifications
8. Apply finished foam

23. PP = NP + FL + EL PP: Pump Pressure NP: Nozzle Pressure
know the manufacturer’s specifications
FL: Friction Loss
determined by field tests or by calculations
includes hose and appliances
EL: Elevation Loss
approximately 0.5 psi/ft (vertically)

24. C = Coefficient specific to hose construction
2 FL = CQ L + A
C = Coefficient specific to hose construction
Q = Quantity of water in hundreds of gpm
L = Length of hose in hundreds of feet
A = Appliances: siameses, wyes, master stream devices, etc.

25. Strategic Objectives ( in order of importance)
Rescue: direct streams to protect victims and rescuers
Exposure Protection: nearby combustibles
Interior: areas of the fire building not involved
Exterior: adjacent buildings
Confinement: coordinate streams and ventilation to attack and contain the fire
Extinguish: apply sufficient streams to seat of fire to reduce heat and heat production

26. Types of Attack Offensive: direct interior attack
greatest risk to firefighters
IC must weigh fire and building conditions, life hazards, and building construction type
must be coordinated with ventilation efforts
attack crews must understand the principles of fire spread
streams must be of adequate size and appropriate type to achieve the tactical objectives

27. Types of Attack (cont.)
Defensive: goal is to contain fire to building involved (“written off”)
used when available fire flow is insufficient or,
structure is obviously lost, regardless of flow, or
repeated interior attacks have failed, or
structural stability is compromised, or
interior crews’ safety is questionable
Direct streams to protect last-minute rescue and interior attack crews’ egress

28. Types of Attack (cont.) Defensive (cont.):
concentrate on protecting exposures
remove apparatus, crews, appliances, and hose lines from collapse zone
attack fire from outside with monitors and elevated master streams