Download presentation
Presentation is loading. Please wait.
Published byLynette Carpenter Modified over 9 years ago
1
PREINCIDNET PREPARATION
2
OBJECTIVES Properly calculate required fire flow for structures using the National Fire Academy Fire Flow Formula. FIRE FLOW REQUIREMENTS FIRE FLOW FORMULA Module 5 Overview
3
OBJECTIVES Given the required fire flow for a structure, estimate the personnel required for offensive operations. RESOURCE CAPABILITY AND DISTRIBUTION DATA Module 5 Overview
4
OBJECTIVES Given a scenario, properly complete a National Fire Academy Quick Access Prefire Plan QUICK ACCESS PREFIRE PLANNING Module 5 Overview
5
FIRE FLOW REQUIREMENTS Fires extinguished by absorbing the heat with water Application of water will: –Absorb heat –Reduce temperature –Extinguish fire
6
FIRE FLOW REQUIREMENTS To extinguish a fire, the quantity of water (gpm) must exceed the heat (Btu’s) being produced.
7
FIRE FLOW FORMULA QUICK CALCULATION Basic Formula: Length x Width = GPM 3
8
CALAULATES THEORETICAL FIRE FLOW Large amounts of heat absorbed Reduces temperature below ignition temperature Fire is “blacked-out” ready for overhaul
9
WITH HIGH PERCENTAGES OF INVOLVEMENT INTERIOR OPERATIONS ARE NOT POSSIBLE 100% involvement answer is theoretical Starting point for realistic flow rate Starting point for defensive operations Tactical operations must be evaluated
10
ORIGIN OF FORMULA Empirical formula developed by NFA development team. Study of fire flow at fire situations
11
BASIC FORMULA Basic Formula: L x W = GPM 3 Flow for one floor fully involved. Estimate Length/Width to nearest 10 feet. Multiply L x W then divide by 3. Theoretical fire flow for 100% involvement.
12
Insert 1 story 40’x 30’ structure- no fire 30 X 40
13
BASIC FORMULA Quick calculations at the scene Calculates water required for: –Confinement, Extinguishment, Back-up lines
14
Insert 50’ x 30’ building with dimensions on slide 50x30
15
MULTIPLE STORIES Multiply base fire floor by number of floors
16
Insert 2 story house (50 ft X 30 ft /3) x 2 = FULLY INVOLVED = 1000 GPM 50% INVOLVED = 500 GPM 25 % INVOLVED = 250 GPM
17
EXPOSURES GPM = LENGTH X WIDTH + EXPOSURES 3
18
WATER FOR EXPOSURE PROTECTION Interior exposures - floors above the fire on “fire-resistive” construction Exterior exposures - buildings or other objects
19
EXPOSURE PROTECTION Up to 4 floors above the fire Buildings or other objects 0 to 30’ -- usually an exposure 30’ to 100’ -- could be an exposure 100’ or more -- usually not an exposure
20
You must make the final determination of exposure based on observed conditions
21
EXPOSURE PROTECTION Fire area adjacent to a fire wall Should the exposure become involved - calculate flow as new fire building
22
EXPOSURE PROTECTION Exposure “C” 25% Exposure “B” Fire Exposure “D” 25% Building 25% Exposure “A” 25%
23
Exposure Fire Building Exposure “B” “D” Base Flow = 1000 GPM Exposure “B” = 250 GPM (25%) Exposure “D” = 250 GPM (25%)
24
INTERIOR EXPOSURE ( Fire Resistive Structure) 5 EXPOSURE 25% 4 EXPOSURE 25% 3 EXPOSURE 25% 2 EXPOSURE 25% 1 FIRE FLOOR
25
EXPOSURE PROTECTION “Fire Resistive” Structure 25% Exposure “B” 250 gpm 25% Exposure “D” 250 gpm 3 Exposure 250 gpm (25%) 2 Exposure 250 gpm (25%) 1 Fire Floor Total Fire Flow = 1000 GPM Total Exposure Flow = 1000 GPM Total Flow Required = 2000 GPM
26
PERCENTAGE OF INVOLVEMENT GPM = L x W + EXPOSURE x PERCENT OF INVOLVEMENT 3
27
PERCENTAGE OF INVOLVEMENT Fire Building Exposure “D” 1000 GPM 250 GPM (25%) 100% Involvement = 1250 GPM 75% Involvement = 950 GPM (1250 x.75) 50% Involvement = 625 GPM (1250 x.50) 25% Involvement = 325 GPM (1235 x.25)
28
Individual Activity 5.1 Fire Flow Calculation
29
15’ 20’ Fire building is 30’x 50’ Exposure B Fire Building 20’ Exposure D15’
30
RESOURCE CAPABILITY AND DISTRIBUTION DATA
31
KNOW INITIAL ATTACK CAPABILITY Measured in terms of ability to flow GPM If fire flow requirements exceed resources, get help
32
RESOURCE CAPABILITY AND DISTRIBUTION DATA Capability/Distribution evaluation parameters Requires an aggressive interior fire attack
33
INTERIOR FIRE ATTACK FLOW RATES AND PERSONNEL REQUIRED Hose size Flow Rates Personnel/Lines 1-1/2” 100 gpm 2 1-1/2” 150 gpm 2 1-3/4” 150 gpm 2 2” 240 gpm 3 2-1/2” 300 gpm 4+
34
FOUR MAJOR FUNCTIONS ON THE INCIDNET SCENE COMMAND VENTILATION SEARCH FIRE CONTROL
35
Insert building fire 40’ x 90’ slab foundation “Distribution at simple incidents”
36
FIRE INVOLVEMENT 1-story structure 40 x 90 (3600 Sq. Ft) built on a slab 25% involvement, no exposures gpm = 300
37
Personnel Requirement Incident Commander 1 Ventilation 2 Primary Search/Fire Attack/ Pump Operation 7 Total Personnel Required 10
38
Insert 2 story building fire - lot’s of fire-Titled- distribution at complex incident Distribution at complex incident 60 X 60
39
FIRE INVOLVEMENT 2-story structure 60 x 60 (3600 Sq. Ft) built on a slab 25% involvement, 1 second floor exposure gpm = 600
40
Incident Commander 1 1st and 2nd Floor Supervisors 2 Ventilation 4 Primary Search/Fire Attack/ Pump Operation 4- 1-3/4” lines 12 Total Personnel Required 19
41
CONCLUSION gpm divided by personnel = gpm per person 300 gpm divided by 10 persons = 30 gpm per person
42
CONCLUSION gpm divided by personnel = gpm per person 600 gpm divided by 19 persons = 31.5 gpm per person
43
ANALYSIS The average fire flow on the incident scene in the United States ranges between 25 and 50 gpm per person engaged in fire control efforts, as stated in the charts above.
44
ANALYSIS If the fire flow is below 25 gpm/person, you are probably using 1 1/2” hose. Consider switching to 1 3/4” hose; or, you have counted people who are not doing any of the jobs (reserves).
45
ANALYSIS If the fire flow is greater than 50 gpm/person, you either have too few people doing ventilation and primary search; or you are using too few people on each hoseline. NO master streams allowed during interior attack.
46
PROACTIVE USE OF THE DATA Have each unit that responds report the number of personnel on board. Multiply your department’s average flow per person to get your total capability responding to this alarm.
47
PROACTIVE USE OF THE DATA What total flow for 10 personnel? What total flow for 15 personnel? What total flow for 20 personnel?
48
INTERIOR FIRE ATTACK AND PERSONNEL REQUIRED Hose size Flow Rates Personnel/Line 1-1/2” 100 gpm 2 1-3/4” 150 gpm 2 2” 150 gpm 2 1-3/4” 240 gpm 3 2” 240 gpm 3 2-1/2” 300 gpm 4+
49
Large Group Activity 5.2: Personnel Capability and Distribution Data
50
Insert 1 story building, 50’ x 90’ approx 25% involved
51
QUICK ACCESS PERFIRE PLANNING
52
WHO DOES THE PREFIRE PLANNING Proactive fire departments Chief officers leading professional departments Professional fire officers –paid/volunteer
53
PURPOSE For first-in officers A form from which you can read important data Does not take the place of a more detailed prefire plan for complex facilities Training reference for target hazards
54
BUILDINGS REQUIRING A PREFIRE PLAN Target hazards Other important structures/facilities Consider smaller structures
55
WHO USES QUICK ACCESS PREFIRE PLANNING First-in company officers/chief officers Later arriving chief officers Training Officers
56
Large Group Activity 5.3: Quick Access Preplanning
57
Insert slide # 57, module 5
58
Insert slide # 58, module 5
59
Insert slide # 59, module 5
60
Insert slide # 60, module 5
61
Insert slide # 61, module 5
62
Insert slide # 62, module 5
63
Insert slide # 63, module 5
64
Insert slide # 64, module 5
65
Insert slide # 65, module 5
66
Insert slide # 66, module 5
67
Insert slide # 67, module 5
68
Insert slide # 68, module 5
69
Insert slide # 69, module 5
70
Large Group Activity 5.4: Building Construction and Fire Behavior Predictions
71
Single family
72
Single family fire shot
73
Apartment shots / multi angle and fire
75
Large single family use micto stuff
76
Large single
77
Large single strip
79
Wheels in motion fire today
81
Wheels in motion fire
83
Wheels after fire
84
Large mercantile
85
highrise
87
Ordinary construction
89
Insert slide #89, module 5
91
Insert slide #91, module 5
92
Insert slide #92, module 5
93
Insert slide #93, module 5
95
Insert slide #95, module 5
98
SUMMARY Fire flow requirements must be understood because of the effect on tactical decisions, resource needs, and safety concerns on the incident scene. Knowing your resource capability in terms of gpm per person on the scene assists in decision making.
99
SUMMARY Prefire planning provides “must know” information which increases one’s ability to make correct decisions at an incident.
Similar presentations
© 2025 SlidePlayer.com. Inc.
All rights reserved.