NFPA 1142
STANDARD ON WATER STANDARD ON WATER SUPPLIES FOR SUBURBAN SUPPLIES FOR SUBURBAN AND RURAL FIRE FIGHTINGAND RURAL FIRE FIGHTING
NFPA 1142 WATER SUPPLY WATER SUPPLY DETERMINING FACTORSDETERMINING FACTORS
•EXTENT OF EVOLUTIONSEXTENT OF EVOLUTIONS
•SIZE OF and TYPE OF STRUCTURESIZE OF and TYPE OF STRUCTURE
•CONTENTSCONTENTS
•METHOD OF ATTACKMETHOD OF ATTACK
•EXPOSURESEXPOSURES
•RESERVESRESERVES
NFPA 1142
NFPA 1403: 4.2 Structures and NFPA 1403: 4.2 Structures and FacilitiesFacilities
4.2.234.2.23The lead instructor shall determine the rate
and duration of water flow necessary ..., including the water necessary for control
and extinguishment of the training fire, the supply necessary for backup lines to protect personnel, and any water needed to protect
exposures.
NFPA 1142
NFPA 1403: 4.2 Structures and NFPA 1403: 4.2 Structures and FacilitiesFacilities
4.2.23.14.2.23.1The minimum water supply and delivery for the live fire training
evolutions shall meet the criteria identified in NFPA 1142, Standard on
Water Supplies for Suburban and Rural Fire Fighting.
NFPA 1142
Definition: 4.1.5Definition: 4.1.5
(1) Exposure HazardSTRUCTURE WITHIN 50 FEET and
100 SQUARE FEET OR LARGER.
(2) If class 3 or 4 OH, within 50 ft of another building, (2) If class 3 or 4 OH, within 50 ft of another building, it is considered an exposure hazard regardless of it is considered an exposure hazard regardless of size.size.
NFPA 1142
Chapter 5Chapter 5
CLASSIFICATION OF OCCUPANCY HAZARD
WHAT OCCUPANCY TYPE IS THE MOST LIKELY TO BE USED IN LIVE
FIRE TRAINING?
NFPA 1142
NFPA 1142 5.2.5NFPA 1142 5.2.5
Occupancy Hazard Classification 7
5.2.5.1 Light hazard occupancy
Dwellings
NFPA 1142
Classification Of ConstructionClassification Of Construction
6.2 .... structures shall be classified by type of
construction and shall be assigned a construction classification number.
NFPA 1142
Classification Of ConstructionClassification Of Construction
6.2.1 Type V (Wood Frame) Construction Classification Number
1.5
Dwellings
NFPA 1142
Chapter 4Minimum Water Supply = Minimum Water Supply =
(TOTAL CUBIC FT)(TOTAL CUBIC FT) x (CONST CLASS OCCUP 1.5) x ( Exp. Factor 1.5) x (CONST CLASS OCCUP 1.5) x ( Exp. Factor 1.5)
(CLASS # 7)(CLASS # 7)
PER 1142PER 1142 - -
FOR ALL EXPOSURE HAZARDS FOR ALL EXPOSURE HAZARDS MULTIPLY TOTAL BY: MULTIPLY TOTAL BY:
1.51.5
NFPA 1142
NFPA 1142NFPA 1142
4.2 SINGLE STRUCTURES WITHOUT EXPOSURE 4.2 SINGLE STRUCTURES WITHOUT EXPOSURE HAZARDS HAZARDS
(2000 gal. minimum)(2000 gal. minimum)
4.3 SINGLE STRUCTURES WITH EXPOSURE 4.3 SINGLE STRUCTURES WITH EXPOSURE HAZARDSHAZARDS
(3000 gal. minimum)(3000 gal. minimum)
NFPA 1142
NFPA 1403NFPA 1403
50% Reserve50% ReserveSINGLE STRUCTURES WITHOUT EXPOSURE SINGLE STRUCTURES WITHOUT EXPOSURE
HAZARDS HAZARDS
(3000 gal. minimum)(3000 gal. minimum)
SINGLE STRUCTURES WITH EXPOSURE SINGLE STRUCTURES WITH EXPOSURE HAZARDSHAZARDS
(4500 gal. minimum)(4500 gal. minimum)
NFPA 1142
Determining Minimum Water Determining Minimum Water SuppliesSupplies
4.64.6
The fire department shall develop the capability to The fire department shall develop the capability to deliver the amount of water determined in deliver the amount of water determined in
accordance with Sections 4.2 through 4.5 to the accordance with Sections 4.2 through 4.5 to the incident scene at the rate shown in incident scene at the rate shown in
Table 4.6.1Table 4.6.1
NFPA 1142
Table 4.6.1Table 4.6.1
Total Water RequiredTotal Water Required: : Rate CapabilityRate Capability::
< 2,500< 2,500
2,500 - 9,9992,500 - 9,999
10,000 - 19,99910,000 - 19,999
> 20,000> 20,000
250250
500500
750750
1,0001,000
NFPA 1142
What if the exposure is What if the exposure is larger than the structure larger than the structure
being burned?being burned?
Calculate water supply based on the larger structure
NFPA 1142
Multiple Exposures?Multiple Exposures?
NCFRC Exception Add .5 for each Exposure
Example: 2 Exposures 1.5 1st Exposure + .5 2nd Exposure
2.0 Exposure Factor
NFPA 1142
3 Exposures = 1.5 + .5 + .5 = 2.5 (1) (2) (3)
4 Exposures = 1.5 + .5 + .5 + .5 = 3.0 (1) (2) (3) (4)
NFPA 1142
Determining Minimum Water Determining Minimum Water SuppliesSupplies
A minimum reserve of additional water in the amount of 50 percent of the fire flow demand in 4.2.23.1 shall be available to
handle exposure protection or unforeseen situations.
Go back to NFPA 1403: 4.2.23.2
NFPA 1142
Practice Time!
See if your calculations are the same!
(Remember – calculate gable roofs as ½ the height from the attic floor to the ridge pole)
NFPA 1142
50 x 24, 2 stories with gable roof,8’ from attic floor to ridgepole
50’
2 story w/gable roof 8’ ceilings 8’ to ridgepole
24’
(Dwelling)
Exposure
Table 4.6.1 shows: 500 GPM
Must be capable of flowing 500 GPM
for about 15 minutes. (7715 gal / 500GPM)
50% additional reserve per
NFPA 1403: 11,573 Total Gallons11,573 Total Gallons
Go to Table 4.6.1
1 EXPOSURE HAZARD(multiply by 1.5) 7715 GAL.
OCCUP HAZ CLASS = 7(divide by 7) 3429 GAL.CONST CLASS = 1.5(multiply by 1.5) 5144 GAL.
50 X 24 = 1,200 square ft. Height = 8 + 8 + 4* = 20’1,200 x 20 = 24,000 cubic ft.
Exp.
NFPA 114265’ x 30’ = 1,950 square ftHeight = 8’ + 4* = 12 ft.1,950 x 12’ = 23,400 cubic ft
65’
1 story w/gable roof8’ ceilings
8’ to ridgepole
Dwelling
Exposures
Go to Table 4.6.1
750 GPM Flow for about 14 minutes (10,029 gal / 750 GPM)
Exp.
50% additional per NFPA 1403:
15,044 Total Gallons15,044 Total Gallons
2 EXPOSURE HAZARDS(multiply 1 + .5 + .5) 10,029 Gallons
OCCUP HAZ CLASS = 7(divide by 7) 3343 GAL.
CONST CLASS = 1.5(multiply by 1.5) 5014 GAL.
30’
Exp.
NFPA 114252’ x 44’ = 2,288 square ftHeight = 10’ + 10’ + 10* = 30’2,288 x 30’ = 68,640 cubic ft 52’
2 story w/ mansard roof
10’ ceilings
Dwelling
Exposures
Go to Table 4.6.1
1000 GPM Flow for about 37 minutes (36,772 gal / 1000 GPM)
Exp.
50% additional per NFPA 1403:
55,158 Total Gallons55,158 Total Gallons
3 EXPOSURE HAZARDS(1.5 + .5 + .5 = 2.5) 36,772 Gallons
OCCUP HAZ CLASS = 7(divide by 7) 9806 GAL.
CONST CLASS = 1.5(multiply by 1.5) 14,708 GAL.
44’
Exp.
Exp.
NFPA 1142
Remember!Remember!
• Calculate Square Footage• Calculate Cubic Footage• Occupancy Hazard Class• Construction Class• Exposure factor• Required GPM• Minutes Flow Sustained• 1403 Reserve