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