Provide abort switches that are the "dead-man" type. The abort switch shall be used in
conjunction with valves and equipment that will prohibit the discharge of AFFF or water from
the low-level fire suppression system, regardless of whether the low-level fire suppression
system has been activated. The fire suppression system control/release panel shall supervise the
abort switches and their wiring.
The foam concentrate piping shall use stainless steel pipe with roll grooved fittings,
welded joints and fittings, or flanged joints and fittings. If using welded joints and fittings,
consideration shall be given to the maintenance of the system and provide flanged joints at
certain locations to allow for the ease of maintenance. The trim piping on all deluge valves, flow
control valves, and alarm check valves shall utilize brass piping. Any concealed concentrate
piping shall use welded or flanged fittings. The fittings and gaskets shall be made of EPDM.
A reserve foam tank is only required for systems that use bladder tanks.
Note: For remote locations, it is recommended to have a reserve supply of AFFF available on
base for refill purposes.
The AFFF concentrate tank(s) shall be provided with spill containment, i.e., provide
berm to contain any spill or leak.
Provide manual release stations for activation of the low-level fire suppression systems
and the preaction sprinkler systems (if used). Fire alarm manual pull stations and AFFF manual
release stations shall be protected (i.e., hard plastic protective covers) from accidental activation.
AFFF manual release stations shall be distinctively identified, by color, from the fire alarm
manual pull stations. The AFFF manual release stations shall be provided with signage to
identify which system(s) will discharge when the release station is activated.
Fire detection and actuation system control panels must be installed in an
environmentally controlled area that maintains temperature and humidity in accordance with the
manufacturer's listing/approval, but not less than 60 F (15 C). Ensure that the control panels
are not subject to water leakage/runoff from building equipment.
For connections between potable water systems and systems containing foam, provide
a reduced-pressure backflow preventer. For calculation purposes, a friction loss of at least 15 psi
(104 kPa) across the reduced-pressure backflow preventer or 5 psi (35 kPa) higher than the
manufacturer's listed pressure loss, whichever is greater, shall be calculated.
Hand hose stations shall not be provided.
Provide a listed expansion chamber of appropriate size and pre-charged air pressure to
compensate for thermal expansion in the automatic wet pipe sprinkler system in the aircraft
storage and service areas.
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19 January 2005