TM 5-840-2
CHAPTER 6
SPECIAL STORAGE AREAS
6-1. Flammable and combustible storage
devices or scuppers. The elevation, size and
areas.
number of scuppers within a storage module will be
such to prevent the migration of fire water into
a. Size and location requirements. The size of
adjoining building areas. Scuppers will be provided
flammable and combustible storage warehouses will
on exterior walls only, be as small as possible,
be dependent upon the volume of stored material.
provide automatic drainage, and prevent rain,
Certain specifications will be followed in
snow, insects, or rodents from entering a facility.
determining the shape. The warehouse will be
An emergency drainage system will be provided
single-story construction, built along a longitudinal
around the exterior of a HAZMAT facility in order
axis (fig 6-1). It should not be longer than 300 m
to prevent contaminating nearby bodies of water
(1,000 ft) and it should have transverse fire walls
(i.e. lakes, ponds, rivers streams, groundwater,
constructed such that no interior space between fire
etc.). The drainage system, if connected to public
walls is greater than 1850 m2 (20,000 sf). The
sewers or storm drains, will be equipped with traps
building will be detached from any other building
or separators as applicable. The drainage system
and located away from any other building by at
will be in accordance with all applicable Federal,
least 15 m (50 ft). When design considerations
State, and local regulations. If the capture and
allow, the building should be located as far away
containment of discharged fire water is required,
from occupied buildings as possible and situated
the preferred containment system would be via a
with respect to the prevailing wind direction such
remote imponding or ponding area. Imponding dike
that toxic fumes or smoke do not drift over
or berms surrounding a facility will be considered
occupied areas.
only as a secondary alternative. Below ground
b. Construction requirements. Buildings housing
storage tanks will not be used in an emergency
flammable or combustible material should be con-
drainage system. Ramps within the warehouse will
structed from fire-resistive materials or non-
have a maximum grade of 10 percent. Electrical
combustible materials. Floors should be slab-on-
installations will be in accordance with Class I,
grade-type construction made of structural
Division 2, as defined in NFPA 70. When exterior
concrete. Walls should be constructed of fire resis-
wall panels are employed in areas where potential
tant materials of sufficient thickness, and designed
for explosion exists, the use of explosion fasteners
to develop a 4-hour fire resistance rating. Fire walls
should be considered. Should an explosion occur,
should be constructed to limit internal areas to
these fasteners would allow the panels to "break
1850 m2 (20,000 sf) of clear storage space. Doors
away" upon absorbing the explosive impact,
should be of the rolling steel type and where
thereby, minimizing the damage to the structural
practicable should be eliminated in fire walls. All
members.
construction and control joints in the floor must be
c. General considerations.
sealed to prevent spills from contaminating the
(1) Drum storage of combustible materials in
subsurface soil or permeating to adjacent modules.
open areas should be in an area with a concrete
A 100 mm (4 in) tall concrete curb will be required
surface and a 150 mm (6 in) berm running entirely
around the base of each storage area's wall con-
around the storage area.
tainment. Each personnel door within a storage
(2) It is preferable that gas cylinders be stored
module will have a 100 mm (4 in) set up. The
in open-sided, concrete slab-type shells in order to
elevation of storage area's floors will be approxi-
minimize the possibility of harm due to build-up of
mately 100 mm (4 in) below adjacent areas (hall-
a combustible, flammable, or toxic gas if the
ways and shipping/receiving). Hallways and ship-
cylinder should leak.
ping/receiving areas will be the same elevation, but
(3) Construction of gas cylinder storage should
will be recessed approximately 50 mm (2 in) below
conform to the requirements set forth in DOD
the exterior grade. The discharge of fire water
4145.19-R1 paragraph 5-405(d).
within a storage area will be contained to a certain
(4) Positive ventilation systems should be
extent by the internal spill containment curbs. Once
planned into the design of enclosed flammable and
the liquid level within the room reaches the top of
combustible storage areas to prevent the possibility
the curbs, it should immediately be discharged to
of explosive vapor build-up.
the exterior of the facility by means of overflow
6-1
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