Fire Protection Design Manual - Office of Construction and Facilities ...

September-2011
5. WATER SUPPLY FOR FIRE PROTECTION
5.1 Adequacy of Water Supply: Assess adequacy of the existing water supply. Perform water
supply flow testing of fire hydrants and/or fire pumps. If data is available from the facility, the
designer must verify the locations involved as well as the quality and accuracy of the data.
A Provide a secondary fire suppression water supply if required in either of the Physical
Security Design Manuals for VA Facilities.
Note: VA has published two Physical Security Design Manuals that cover Mission Critical
Facilities and Life Safety Protected Facilities. As of 3/2011, only the Mission Critical
Facilities are required to have a secondary water supply for fire protection.
B. Design the secondary water supply to meet the largest expected fire demand (sprinkler
system plus fire hose requirements) for the duration specified in paragraph 5.4. See also 5.2
below and the capacity requirement of the Physical Security Design Manual.
C. Water storage tanks shall be designed in accordance with NFPA 22 “Standard for Water
Tanks for Private Fire Protection.”
D. New water storage tanks shall be provided with a high and low level water switches that are
connected to the site fire alarm system and initiate supervisory alarm signals.
5.2 Capacity:
A. Non-Sprinklered Buildings: Provide minimum fire flow as shown in Table 5.0. Partiallysprinklered
buildings shall be considered non-sprinklered. Typical building occupancies are
shown for each NFPA 13 hazard classification. Flow demand depends primarily on the type
of construction, occupancy, exposure to the building, access to the building site, and fire
department response. Fires in non-sprinklered buildings require more water because
application of water by fire department hose streams is less efficient and begins later than
sprinklers. Use professional judgment to modify these requirements on a case-by-case basis
depending on the following favorable and unfavorable conditions:
Note: It is recommended that any deviations be forwarded to the respective SFPE for review
prior to incorporating the modification.
1. Favorable Conditions
a. Non-combustible construction
b. Limited exposures
c. Ready access to entire building site by fire department apparatus
d. Quick response by adequately staffed fire department
2. Unfavorable Conditions
a. Combustible construction
b. Moderate or serious exposures
c. Hindrance to fire department apparatus access to building site
d. Delayed response or inadequately staffed fire department
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