Intermediate SFFMA Objectives: 6-02.01 6-02.06 8Hrs
Received
Slide 2
Methods to Reduce Heat and Provide Protection Applying water or
foam directly onto burning material to reduce its temperature
Applying water or foam over an open fire to reduce the temperature
so firefighters can advance handlines Reducing high atmospheric
temperature Firefighter I142 (Continued)
Slide 3
Methods to Reduce Heat and Provide Protection Dispersing hot
smoke and fire gases from a heated area Creating a water curtain to
protect firefighters and property from heat Creating a barrier
between a fuel and a fire by covering the fuel with a foam blanket
Firefighter I143
Slide 4
How Water Extinguishes Fire Primary way is cooling Smothering
by diluting or excluding oxygen Firefighter I144
Slide 5
Heat Absorption When heated to boiling point, water absorbs
heat Visible form of steam is called condensed steam Components of
heat absorption Specific heat Firefighter I145 (Continued)
Slide 6
Heat Absorption Latent heat of vaporization Expansion
capability Effective extinguishment with water generally requires
steam production Firefighter I146 (Continued)
Slide 7
Heat Absorption Water absorbs more heat when converted to steam
than when heated to boiling point Firefighter I147
Slide 8
Characteristics of Water Valuable for Fire Extinguishment
Readily available, relatively inexpensive Has greater
heat-absorbing capacity than most other common agents Water
changing to steam requires large amount of heat Can be applied in
variety of ways Firefighter I148
Slide 9
Solid Stream Produced from fixed orifice, solid-bore nozzle Has
ability to reach areas others might not; reach affected by several
factors Design capabilities Firefighter I149 (Continued)
Slide 10
Solid Stream Velocity of stream a result of nozzle pressure
Nozzle pressure, size of discharge opening determine flow
Characteristics of effective fire streams Flow rate Firefighter
I1410
Slide 11
Advantages of Solid Streams May maintain better interior
visibility than others May have greater reach than others Operate
at reduced nozzle pressures per gallon (liter) than others May be
easier to maneuver Firefighter I1411 (Continued)
Slide 12
Advantages of Solid Streams Have greater penetration power Less
likely to disturb normal thermal layering of heat, gases during
interior structural attacks Less prone to clogging with debris
Firefighter I1412 (Continued)
Slide 13
Advantages of Solid Streams Produce less steam conversion than
fog nozzles Can be used to apply compressed-air foam Firefighter
I1413
Slide 14
Disadvantages of Solid Streams Do not allow for different
stream pattern selections Provide less heat absorption per gallon
(liter) delivered than others Hoselines more easily kinked at
corners, obstructions Firefighter I1414
Slide 15
DISCUSSION QUESTION What type of fire situation would be ideal
for a solid- stream nozzle? Firefighter I1415
Slide 16
Fog Stream Fine spray composed of tiny water droplets Design of
most fog nozzles permits adjustment of tip to produce different
stream patterns Firefighter I1416 (Continued)
Slide 17
Fog Stream Water droplets formed to expose maximum water
surface for heat absorption Desired performance of fog stream
nozzles judged by amount of heat that fog stream absorbs and rate
by which the water is converted into steam/vapor Firefighter I1417
(Continued)
Slide 18
Fog Stream Nozzles permit settings of straight stream, narrow-
angle fog, and wide-angle fog Nozzles should be operated at
designed nozzle pressure Firefighter I1418 (Continued)
Slide 19
Fog Stream Several factors affect reach of fog stream
Interaction of these factors on fog stream results in fire stream
with less reach than that of straight or solid stream Firefighter
I1419 (Continued)
Slide 20
Fog Stream Shorter reach makes fog streams less useful for
outside, defensive fire fighting operations Well suited for
fighting interior fires Firefighter I1420
Slide 21
Fog Stream: Waterflow Adjustment Two types of nozzles control
rate of water flow through fog nozzle Manually adjustable nozzles
Automatic nozzles Firefighter I1421
Slide 22
DISCUSSION QUESTION How should adjustments to the rate of flow
be made? Firefighter I1422
Slide 23
Fog Stream: Nozzle Pressure Combination nozzles designed to
operate at different pressures Designated operating pressure for
most combination nozzles is 100 psi (700 kPa) Firefighter I1423
(Continued)
Slide 24
Fog Stream: Nozzle Pressure Nozzles with other designated
operating pressures available Setbacks of nozzles with lower
operating pressures Firefighter I1424 Courtesy of Elkhart Brass
Manufacturing Company.
Slide 25
Advantages of Fog Streams Discharge pattern can be adjusted for
situation Can aid ventilation Reduce heat by exposing maximum water
surface for heat absorption Wide fog pattern provides protection to
firefighters Firefighter I1425
Slide 26
Disadvantages of Fog Streams Do not have as much
reach/penetrating power as solid streams More affected by wind than
solid streams May disturb thermal layering May push air into fire
area, intensifying the fire Firefighter I1426
Slide 27
Ways Fire Fighting Foam Extinguishes/Prevents Fire Separating
Cooling Smothering Penetrating Firefighter II1427
How Foam is Generated Foams used today are of mechanical type
and before use must be Proportioned Aerated Firefighter II1429
(Continued)
Slide 30
How Foam is Generated Elements needed to produce fire fighting
foam Foam concentrate Water Air Mechanical agitation Firefighter II
1430 (Continued)
Slide 31
How Foam is Generated All elements must be present and blended
in correct ratios Aeration produces foam bubbles to form effective
foam blanket Firefighter II1431
Slide 32
Foam Expansion The increase in volume of foam when aerated
Method of aerating results in varying degrees of expansion Types of
foam Firefighter II1432
Slide 33
Foam Concentrates General Considerations Foam concentrates must
match fuel to which applied Class A foams not designed to
extinguish Class B fires Class B foams designed solely for
hydrocarbon fires will not extinguish polar solvent fires
Firefighter II1433
Slide 34
Class A Foam Increasingly used in both wildland and structural
fire fighting Firefighter II1434 (Continued)
Slide 35
Class A Foam Special formulation of hydrocarbon surfactants
Aerated Class A foam coats, insulates fuels, preventing pyrolysis
and ignition May be used with variety of nozzles Firefighter
II1435
Slide 36
Class B Foam Used to prevent ignition of or extinguish fires
involving flammable and combustible liquids Firefighter II1436
(Continued) Courtesy of Williams Fire & Hazard Control,
Inc.
Slide 37
Class B Foam Firefighter II1437 Used to suppress vapors from
unignited spills of these liquids Several types of Class B foam
concentrates available (Continued)
Slide 38
Class B Foam Manufactured from synthetic or protein base May be
proportioned into the fire stream through fixed system,
apparatus-mounted system, or by portable foam proportioning
equipment Firefighter II1438 (Continued)
Slide 39
Class B Foam Foams such as AFFF and FFFP foam may be applied
with standard fog nozzles or air-aspirating foam nozzles
Firefighter II1439 (Continued) Courtesy of Harvey Eisner.
Slide 40
Class B Foam Rate of application depends on several factors
Unignited spills do not require same application rates as ignited
spills To be most effective, blanket of foam 4 inches (100 mm)
thick should be applied to fuel surface Firefighter II1440
Slide 41
Specific Application Foams Numerous types of foam available for
specific applications Properties of foams vary Firefighter
II1441
Slide 42
Proportioning Mixing of water with foam concentrate to form
foam solution Most concentrates can be mixed with fresh/salt water
Firefighter II1442 (Continued)
Slide 43
Proportioning For maximum effectiveness, foam concentrates must
be proportioned at designated percentage Most fire fighting foams
intended to be mixed with 94 to 99.9 percent water Firefighter
II1443 (Continued)
Proportioning Methods Batch-mixing Premixing Firefighter II1446
Courtesy of Ansul.
Slide 47
Firefighter II1447 DISCUSSION QUESTION What proportion methods
does your department use?
Slide 48
Foam Proportioners General Considerations May be portable or
apparatus-mounted Operate by one of two basic principles
Firefighter II1448 Courtesy of Conoco/Phillips.
Slide 49
Portable Foam Proportioners Simplest, most common form of
proportioning devices In-line foam eductors Foam nozzle eductors
Firefighter II1449
Slide 50
Apparatus-Mounted Proportioners Mounted on structural,
industrial, wildland, and aircraft rescue and fire fighting
apparatus, as well as on fire boats Three types Firefighter
II1450
Slide 51
Firefighter II1451 DISCUSSION QUESTION What is the advantage of
an apparatus-mounted proportioner?
Slide 52
Compressed-Air Foam Systems (CAFS) Newer structural engines are
equipped with CAFS Firefighter II1452 (Continued)
Slide 53
Compressed-Air Foam Systems (CAFS) Standard centrifugal pump
supplies water, direct- injection foam-proportioning system mixes
foam solution with water on discharge side of pump, onboard air
compressor adds air to mix before discharging from engine
Firefighter II1453 (Continued)
Slide 54
Compressed-Air Foam Systems (CAFS) Unlike other systems,
hoseline contains finished foam Advantages Disadvantages
Firefighter II1454
Medium- and High-Expansion Foam Generating Devices Produce foam
that is semistable with high air content Medium-expansion foam
High-expansion foam Water-aspirating type nozzle Mechanical blower
generator Firefighter II1456
Slide 57
Reasons for Poor-Quality Foam/ Failure to Generate Foam
Eductor, nozzle flow ratings do not match so foam concentrate
cannot induct into fire stream Air leaks at fittings cause loss of
suction Firefighter II1457 (Continued)
Slide 58
Reasons for Poor-Quality Foam/ Failure to Generate Foam
Improper cleaning of proportioning equipment causes clogged foam
passages Nozzle not fully open, restricting water flow Firefighter
II1458 (Continued)
Slide 59
Reasons for Poor-Quality Foam/ Failure to Generate Foam Hose
lay on discharge side of eductor is too long Hose is kinked and
stops flow Nozzle is too far above eductor Firefighter II1459
(Continued)
Slide 60
Reasons for Poor-Quality Foam/ Failure to Generate Foam Mixing
different types of foam concentrate in same tank results in mixture
too viscous to pass through eductor Firefighter II1460
Slide 61
Roll-On Foam Application Method Directs foam stream on ground
near front edge of burning liquid spill Foam rolls across surface
of fuel Firefighter II1461 (Continued)
Slide 62
Roll-On Foam Application Method Firefighters continue to apply
foam until spreads across entire surface of fuel and fire
extinguished Used only on pool of liquid fuel on open ground
Firefighter II1462
Slide 63
Bank-Down Foam Application Method May be employed when elevated
object is near/ within area of burning pool of liquid or unignited
liquid spill Object may be wall, tank shell, similar vertical
structure Firefighter II1463 (Continued)
Slide 64
Bank-Down Foam Application Method Foam stream directed onto
object, allowing foam to run down onto surface of fuel Used
primarily in dike fires, fires involving spills around damaged/
overturned transport vehicles Firefighter II1464
Slide 65
Rain-Down Foam Application Method Used when other two methods
not feasible because of size of spill area or lack of object from
which to bank foam Firefighter II1465 (Continued)
Slide 66
Rain-Down Foam Application Method Primary manual application
technique on aboveground storage tank fires Directs stream into air
above fire/spill, allows foam to float gently down onto surface of
fuel Firefighter II1466
Slide 67
Firefighter II1467 DISCUSSION QUESTION What are some examples
of when each of these techniques should be used?
Slide 68
Foam Hazards to Humans Foam concentrates pose minimal health
risks to humans May be mildly irritating to skin, eyes Firefighter
II1468 (Continued)
Slide 69
Foam Hazards to Humans Affected areas should be flushed with
water Some concentrates, vapors may be harmful if ingested/inhaled
Consult MSDS for specific information Firefighter II1469
Slide 70
Foam Hazards to Equipment Most Class A, Class B foam
concentrates are mildly corrosive Follow proper flushing procedures
to prevent damage Firefighter II1470
Slide 71
Foam Hazards to Environment Primary impact is effect of
finished foam after application to fire/liquid spill
Biodegradability of foam determined by rate at which environmental
bacteria cause decomposition Firefighter II1471 (Continued)
Slide 72
Foam Hazards to Environment Environmental impact of foam
concentrates varies In the U.S., Class A foams should be approved
by USDA Forest Service Firefighter II1472 (Continued)
Slide 73
Foam Hazards to Environment Chemical properties of Class B
foams and environmental impact vary on type and manufacturer
Protein-based foams safer for environment Firefighter II1473
(Continued)