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Fire Streams

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Title: Fire Streams


1
Fire Streams
  • Essentials of Fire Fighting
  • NFPA 1001
  • Fire Streams SFFMA 6-1.1, 1.3, 1.5 1.9

2
Definition
  • Fire Stream A stream of water or other
    water-based extinguishing agent after it leaves
    the fire hose and nozzle until it reaches the
    desired point.

3
Fire Streams are used to reduce temperatures and
to provide protection through
  • Direct application to burning material
  • Reduction of high atmospheric temperature
  • Dispersal of hot smoke and fire gases from a
    heated area
  • Reduction of temperature over a fire to permit
    closer proximity with handlines
  • Use of water curtain to protect firefighters and
    property from heat

4
What influences the fire stream as it leaves the
nozzle?
  • Pressure
  • Nozzle design
  • Nozzle adjustment
  • Condition and size of nozzle orifice

5
What influences a fire stream as it passes
through space?
  • Its velocity
  • Gravity
  • Wind
  • Friction with air

6
What are the three physical states of water, and
at what temperature do they occur?
  • Liquid, between 32F and 212F
  • Solid, 32F
  • Vapor/steam, 212F

7
Water is a compound of hydrogen and oxygen. What
is the ratio of hydrogen to oxygen in water?
  • Two parts hydrogen to one part oxygen H2O

8
What are the primary ways in which water
extinguishes fire?
  • Cools
  • Smothers

9
Can water be compressed?
  • No

10
About how much does water weigh per cubic foot in
its liquid state?
  • Approximately 62.5 lb/ft3

11
When is liquid water heaviest when it is hot or
when it is cold?
  • When it is cold

12
What is a BTU?
  • British thermal unit amount of heat needed to
    raise the temperature of 1 pound of water 1F

13
After water reaches 212F (100C) begins to be
converted to steam how many BTUs are required
per pound of water for complete vaporization?
  • 970 BTUs

14
What factors, more than any other, determine how
much heat water can absorb?
  • Its surface area. The greater the surface area,
    the more heat water can absorb

15
What happens to water as it is converted to steam?
  • At 212 F occupies 1,700 times the original
    volume
  • Absorbs more heat faster, cooling fuel below
    ignition temperature
  • Displaces hot gases, smoke, and other products of
    combustion
  • In some cases, may smother fire by excluding
    oxygen

16
Remember
  • Water is unique in that it expands both upon
    freezing and upon changing into its vapor state

17
What is the significance to fire fighting of
waters unique feature?
  • Water in pipes subject to freezing (undrained
    automatic sprinkler piping in unheated buildings,
    wet barrel hydrants, shallowly buried underground
    pipes) may rupture
  • The 17001 expansion ratio during vaporization
    allows water to absorb more heat

18
How is water used as a smothering agent on liquid
fires?
  • By floating on liquids that are heavier than
    water
  • By smothering fires in liquid that are lighter
    than water or with which water is usually
    miscible if a foam concentrate is added to the
    water

Miscible capable of being mixed without
separation
19
Definition
  • Velocity rate of motion of a particle in a
    given direction speed
  • Friction Loss pressure lost while forcing water
    through pipe, fittings, fire hose, and adapters
  • Critical Velocity turbulence caused when a
    stream is subjected to excessive velocity

20
What are some causes of friction loss?
  • Rough hose lining
  • Damaged couplings
  • Sharp bends/kinks in hose
  • Needless adapters
  • Partially closed valves/nozzles
  • Wrong size gasket
  • Excessive hose length
  • Excess flow for size of hose
  • Elevation increase

21
How can you tell when critical velocity has been
reached in a hoseline?
  • The entire stream will be agitated by resistance

22
What should be done when critical velocity is
reached in a hoseline?
  • Parallel or siamese hoselines in order to
    increase flow and reduce friction

23
Other than friction loss, what factors may lead
to loss of water pressure in a line?
  • Broken hoseline
  • Mechanical problem due to poor water supply
  • Error in hydraulic calculation
  • Obstructions from the pump or water main

24
Water Hammer
  • Is caused by suddenly stopping the flow of water
    through the fire hose or pipe
  • Often heard as a distinct clank, much like a
    hammer striking a pipe
  • Causes a change in direction of energy and
    multiplies the energy many times

25
What pieces of equipment can be damaged by water
hammer?
  • Pumps
  • Hoselines
  • Water mains
  • Couplings
  • Nozzles
  • Hydrants

26
Water Fire Streams
27
What four essentials are needed to produce an
effective fire stream?
  • Extinguishing agent
  • Pressure device
  • Hose
  • Nozzle

28
Fire streams classified by discharge rate
  • Low-volume Streams
  • Discharge less than 40 gpm
  • Handline Streams
  • Discharge 40 to 350 gpm
  • Master Streams
  • Discharge 350 to 1,000 gpm
  • Fed by 2 ½ to 3 inch and larger lines

29
Fire streams classified by stream characteristics
  • Broken
  • Coarsely divided drops of varied sizes
  • Good heat absorption
  • Solid
  • Little shower or spray
  • Good reach and penetration
  • Fog
  • Fine particles
  • Definite pattern
  • High water to steam ratio

30
What is the difference between a solid stream and
a straight stream?
  • Solid stream is produced from a fixed orifice,
    smoothbore nozzle
  • Straight stream is produced from an adjustable
    fog nozzle

31
When are solid streams used?
  • For exterior attack when a powerful,
    long-ranging, high-volume stream is desired
  • In some cases, solid streams may be used for an
    interior attack

32
What is meant by the term breakover point?
  • That point at which a solid stream begins to lose
    its forward velocity

33
Physical characteristics of a good solid stream
  • At point of breakover has not lost its continuity
    by breaking into showers of spray
  • Remains stiff enough to maintain the height
    required even with a moderate breeze blowing
  • Shoots nine-tenths of its volume of water within
    a stream diameter at breakover of 15 inches and
    three-quarters of it inside a 10-inch stream
    diameter

34
What is the difference between a fog stream and a
broken stream?
  • Fog stream is composed of small droplets, has a
    definite pattern, and is usually adjustable
  • Broken stream is usually composed of larger
    droplets, does not have a definite pattern, and
    is generally not adjustable

35
When are fog streams generally used?
  • Interior extinguishment through heat absorption
  • Displacement of heated gases
  • To provide a protective water curtain between the
    fire and a firefighter or a combustible material

36
At what pressure should fog stream nozzles be
operated?
  • 100 psi

37
Fog stream patterns
  • Straight Stream
  • Straight water pattern
  • Greatest reach lowest surface area coverage
  • Narrow Fog
  • Spread water pattern 15 to 45
  • Mid-range reach and surface area coverage
  • Wide Fog
  • Spread water pattern 45 to 90
  • Greatest surface area coverage lowest reach

38
What other factors affect the reach of a fog
stream?
  • Gravity
  • Water velocity
  • Water droplet size
  • Friction with air
  • Wind

39
Broken Streams
  • A broken fire stream is one that is as its name
    implies broken into coarsely divided drops
  • The droplets of a broken stream are larger than
    those of a fog nozzle and have greater
    penetration and are less prone to wind deformity
    or destruction
  • The stream may be broken through reactionary
    forces, deflection, or with specialized nozzles

40
Producing a broken stream (reaction)
  • Creating a broken stream with two solid streams
    intersect

41
Producing a broken stream (deflection)
  • Streams parallel to joists or rafters will be
    deflected as if against an unobstructed ceiling
  • Streams perpendicular to joists or rafters will
    drop immediately onto fire below impact point

42
What is a master stream?
  • A large volume stream that discharges more than
    350 gpm
  • Any fire stream that is too large to be
    controlled without mechanical aid
  • May be solid or fog stream

43
When are master streams used?
  • Used when handlines would be ineffective
  • When conditions are unsafe
  • When manpower is limited

44
Water Nozzles
  • Solid
  • Fog
  • Master

45
Solid stream nozzles parts
  • Playpipe
  • Shutoff
  • Packing
  • Nozzle tip
  • Rubber bumper
  • Gaskets

46
Solid stream nozzles
  • Size of stream gradually reduced in the nozzle
  • True cylindrical bore near discharge tip
  • Compact, tight stream having maximum reach and
    penetration
  • Shutoff valve threaded with 1 ½-inch threads

47
Rules of thumb for solid stream nozzles
  • The discharge orifice should be no larger than
    one-half the diameter of the hose to which it is
    attached
  • The greater the nozzle pressure, the greater the
    reach and the greater the nozzle reaction
  • The greater the volume while maintaining nozzle
    pressure, the greater the reach and the greater
    the nozzle reaction
  • The stream angle should be kept near a 32-degree
    angle with the earths surface for maximum reach

48
Fog nozzle parts
  • Shut-off handle control
  • Ribbed, adjustable tip
  • Handle grip (as applicable)

49
Fog nozzle terms
  • Periphery outward boundary of an object
  • Deflection deviation turn from a given course
  • Impinge encroach infringe come together with
    force

50
Fog nozzles
  • Fog nozzles may be classified by the stream
    pattern formed periphery-deflected stream,
    impinging stream, or impinging/periphery-deflected
    stream

51
Fog nozzles
  • Besides being classified by the mechanics of the
    stream pattern formed, fog nozzles are also
    classified according to their method of operation
    (I.e., whether or not their flow rate gallonage
    is adjustable or nonadjustable

52
Fog nozzles
  • Set gallonage (adjustable fog)
  • Adjustable pattern
  • Nonadjustable flow rate flow rate remains the
    same regardless of the pattern
  • Automatic
  • Adjustable pattern
  • Automatically adjusted flow rate
  • Adjustable gallonage
  • Adjustable pattern
  • Manually adjustable flow rate

53
Master streams
  • Monitor
  • Turret pipe
  • Deluge set
  • Elevated master stream

54
Master streams - Monitor
  • May be fixed, combination, or portable
  • Stream direction and angle can be changed
  • Fixed and combination permanently mounted on the
    apparatus

55
Master streams Turret pipe
  • Mounted on fire apparatus deck
  • Connected directly to pump by permanent pipe
  • Sometimes called a deck gun or deck pipe

56
Master streams Deluge set
  • Short length of large-diameter hose with large
    nozzle or playpipe
  • Supported at discharge end by tripod
  • Has siamese connection at supply end
  • Direction and angle of stream cannot be changed
    during discharge

57
Master streams Elevated master stream
  • Large-capacity nozzles placed on end of aerial
    apparatus elevating device
  • May be permanently attached or detachable
  • May be power operated or manually operated from
    tip of ladder or from aerial platform or may be
    operated using rope from the ground (detachable)

58
Broken stream, special-application nozzles
  • Piercing/penetrating nozzle
  • Chimney nozzle
  • Distributor (cellar) nozzle

59
Master streams - Monitor
  • May be fixed, combination, or portable
  • Stream direction and angle can be changed
  • Fixed and combination permanently mounted on the
    apparatus

60
Broken stream, special-application nozzles
  • Piercing/penetrating nozzle
  • Used with a sledgehammer to drive the point of
    the piercing nozzle through the obstruction

61
Broken stream, special-application nozzles
  • Chimney nozzle
  • A booster hose and nozzle are dropped down the
    entire length of the chimney and then pulled back
    out
  • Mist from the nozzle turns to steam and chokes
    the fire

62
Nozzle inspection procedures
  • Check gasket for wear and cracks
  • Check for external damage
  • Check for internal damage and debris
  • Check ease of operation

63
Nozzle cleaning and maintenance procedures
  • Clean with soap and water and soft bristle brush
  • Replace worn or missing gaskets
  • Lubricate moving parts as needed according to
    manufacturers recommendations

64
Foam
  • Water alone is not always effective as an
    extinguishing agent, and that under certain
    circumstances, fire fighting foam is needed

65
What are the two basic categories of flammable
liquids upon which foam is especially effective?
  • Hydrocarbon fuels
  • Polar solvents

66
What distinguishes a hydrocarbon fuel from a
polar solvent?
  • Hydrocarbons are petroleum based and float on
    water
  • Polar solvents are flammable liquids with an
    attraction for water

67
What are some examples of hydrocarbon fuels?
  • Crude oil
  • Fuel oil
  • Gasoline
  • Benzene
  • Naphtha
  • Jet fuel
  • Kerosene

68
What are some examples of polar solvent fuels?
  • Alcohols
  • Esters
  • Acids
  • Acetone
  • Lacquer thinner
  • Ketones

69
What additional types of fuels/fires is foam used
on?
  • Acid spills
  • Pesticide fires
  • Confined-space fires
  • Deep-seated Class A fires
  • Unignited hazardous materials spills

70
What are the four ways that foam works to
extinguish fires?
  • Cools
  • Smothers
  • Separates
  • Suppresses

71
Foam generation terms
  • Concentrate raw foam liquid in storage
    container
  • Proportioner device that injects correct amount
    of foam concentrate into water stream
  • Solution mixture of foam concentrate and water
    in hoseline
  • Foam product of solution and air mixed at foam
    nozzle

72
How is foam generated?
  • Water is mixed with foam concentrate to form a
    foam solution
  • The foam solution passes through the hoseline to
    a foam maker, which aerates the foam solution to
    form finished foam

73
Four elements necessary to produce a high-quality
fire fighting foam
  • Foam concentrate
  • Water
  • Air
  • Mechanical agitation

74
Fire fighting foam is 90 to 99 water
75
Foam expansion ratios air/solution ratios
  • Low-expansion 51 to 101
  • To extinguish hydrocarbon polar solvent fuels
  • For vapor suppression on unignited spills
  • Medium-expansion 1001 to 3001
  • For fuel liquids not exceeding 250F
  • High-expansion 5001 to 12001
  • For filling space in basements, mine shafts,
    subterranean areas

76
Foam application rate
  • AFFF/FFFP 0.10 gpm/ft2 for ignited
    hydrocarbons
  • Fluoroprotein foam 0.16 gpm/ft2
  • ATC 0.24 gpm/ft2

77
Why dont unignited spills require the same
application rates as ignited spills?
  • Radiant heat, open flame, and thermal drafts do
    not attack the finished foam as they would under
    fire conditions

78
Applying protein foam
  • Get close
  • Apple gently
  • Apply indirectly, allowing to spread over fuel
  • Do not plunge foam into fuel

79
Subsurface fluoroprotein injection
  • Fluoroprotein foam
  • Will shed hydrocarbon fuels
  • Its suited for plunge application
  • Can be applied from a distance
  • Can be injected at base of storage tank

80
What benefits of fluoroprotein foam and AFFF are
incorporated into FFFP foam?
  • FFFP incorporates the benefits of AFFF for fast
    knockdown, and the benefits of fluoroprotein for
    long-lasting heat resistance

81
In reference to AFFF, what is meant by light
water?
  • The aqueous film water that drains from the
    foam blanket and floats on hydrocarbon fuel spills

82
How AFFF foam works
  • Water drained from foam blanket floats on
    hydrocarbon fuel spills
  • The light water sends an air-excluding film
    ahead of foam blanket
  • AFFF can be used with fresh or salt water
  • AFFF is ideal for crash rescue involving spills

83
How do the new low-expansion hazardous materials
vapor mitigating foams work?
  • They provide a blanket that helps to separate the
    liquid and its vapors from heat sources, greatly
    reducing but not completely eliminating the
    rate of vaporization of the liquid

84
Safety guidelines for using high-expansion foam
to attack structure fires
  • Wear SCBA for overhaul and for entry into
    foam-filled passages
  • Avoid entry into foam because it reduces vision
    and hearing
  • If you must enter, cut a path through the foam
    with a coarse water spray if possible
  • Employ a lifeline if you must enter an area
    filled with high-expansion foam
  • Know that foam conducts electricity, and avoid
    using on electrical fires

85
What kind of foam is becoming increasingly
popular for fighting wildland and structure fires?
  • Class A

86
Popular foam nozzles
  • Air-aspirating foam nozzle for generation of
    low-expansion foam
  • Standard fixed-flow fog nozzle for use with AFFF
    foams
  • Self-educating foam nozzle (educator attached to
    nozzle rather than back on the hose as with an
    in-line educator)
  • Automatic nozzle with foam attachment
  • High-expansion foam generator
  • Water-aspirating
  • Mechanical blower

87
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