6 January 2005
PURPOSE. This document provides design criteria for fire protection in Navy and
Marine Corps aircraft hangars.
APPLICATION. This document applies to new or renovated aircraft hangars.
Projects currently under design shall be revised to comply. If schedule and funds are impacted,
contact the NAVFAC cognizant Fire Protection Engineer.
National Fire Protection Association
NFPA 409, "Standard for Aircraft Hangars"
The requirements of NFPA 409 that are not modified by this document shall apply.
All hangars shall be classified as Group I hangars, unless prior approval is obtained from
NAVFAC HQ to construct as Group II or Group III hangars.
The type of construction, internal separations, clear space distance requirements
around hangars, floors, columns, doors, and other features shall comply with the requirements of
Group I hangars in NFPA 409.
When using overhead radiant heat systems, natural gas-fired tube heaters should be
specified for the aircraft servicing area. The use of overhead radiant heat systems that utilize any
heaters with a flame or glowing element open to the atmosphere in the aircraft servicing area
may cause the optical flame detectors to activate when the heaters start up.
Provide a water supply that will support the combined demand of the ceiling sprinkler
system, low-level fire suppression system, and the hose stream allowance.
The hangar aircraft storage and servicing area shall be protected with closed-head
water only sprinkler system and low-level AFFF system. The closed-head water only sprinkler
system can either be wet pipe or preaction sprinkler system. The use of wet pipe or preaction
sprinkler system will depend on climate conditions.
Draft curtains shall be provided in accordance with NFPA 409. The draft curtains
shall extend down from the roof or ceiling of aircraft storage and servicing areas not less than
one-eighth of the height from the floor to roof or ceiling, or to the bottom cord of the truss,
which ever is lower.
Provide trench drains in the aircraft storage and servicing area. The trench drains shall
be spaced a maximum of 50 feet (15.2 m) center-to-center. The location of the trench drains will
depend on the configuration of the hangar. For "Drive-thru" type hangars (see Figure 1), provide
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19 January 2005