ventilation in the area and to remove all sources of
wash fountains and deluge showers installed at
ignition to avoid a possible fire or explosion.
easily accessible locations. Acid storage ware-
Certain plastic adhesive tapes are also being used
houses will contain enough heating equipment to
for this purpose.
prevent freezing of the acid during cold portions of
(d) Care should also be used in removing and
(3) Toxic chemical areas. Floors and walls of
disposing of these coatings. Not only should their
contaminated nature be considered, but some,
areas used to store toxic chemicals will be made of
when burned, liberate corrosive vapors which can
smooth, nonporous materials that will not absorb
cause extensive damage to sensitive equipment.
the chemicals in case of a spill. Porous floors would
make decontamination of a chemical spill difficult.
6-3. Hazardous chemicals.
Due to the nature of stored material, change areas
and shower facilities should be installed for per-
a. There are two areas of safety consideration
sonnel required to work in these areas.
associated with hazardous chemical storage, chem-
(4) Oxidizing chemicals. The NFPA catego-
ical leakage and fire or combustion. Facilities to
rizes liquid and solid oxidizing materials into four
house these chemicals should be designed with both
classes based on the burning property of the oxidize
these considerations in mind. Among these
material when contacting a combustible material:
chemicals are explosive chemicals, flammable
Class 1. An oxidizing material whose primary
chemicals, oxidizing chemicals, toxic and corrosive
hazard is that it may increase the
chemicals, and water-sensitive chemicals.
burning rate of combustible material
b. Construction requirements. Since most of the
with which it comes in contact.
hazards associated with chemical storage involve
Class 2. An oxidizing material that will mod-
combustion, fire, or explosion, the general require-
erately increase the burning rate or
ments for construction should be similar to those
which may cause spontaneous ignition
outlined in paragraph 6-1. However, the nature of
of combustible material with which it
the type of chemical stored should dictate that
comes in contact.
special construction requirements be considered.
Class 3. An oxidizing material that will cause a
(1) Special construction considerations. Main-
severe increase in the burning rate of
tenance of cool surroundings is a condition suited
combustible material with which it
to all chemical storage. Consequently, ventilation
comes in contact or which will undergo
and exclusion of excess heat are important con-
vigorous self-sustained decomposition
struction features. Natural ventilation can be uti-
when catalyzed or exposed to heat.
lized by designing louvers into the walls of the
Class 4. An oxidizing material that can undergo
storage building. Openings placed under the eaves
an explosive reaction when catalyzed or
and just above the floor level will provide good
movement of air in and around containers. Where
Oxidizing chemicals should be kept separated from
a particularly hazardous situation may occur re-
flammable materials since the chemicals provide
quiring a specific number of air changes per hour,
forced ventilation can be achieved by mechanical
process. Fire protection systems in these areas
means. Cool temperatures can be maintained by
should provide a specified water density according
selecting materials that reflect the heat of the sun,
to classification in compliance with the provisions
and by limiting the number of windows allowed
of NFPA Standard 43A and 43C.
within the building.
(2) Acid storage areas. Figure 6-2 shows a
6-4. Open chemical storage.
cross section of an acid storage warehouse. Build-
Certain chemicals are such that they can be stored
ing construction should be single story without
in open storage areas. Chemicals stored in drums
attic or basement and made of noncombustible or
should be given layouts such that all drums are
fire-resistant materials. Sprinkler systems are rec-
easily inspected for leakage and that ready access
ommended as the method of automatic fire protec-
to these drums can be made. Storage of sealed
tion. Spill containment for these areas will be as
drums lying on their sides is preferable to stacking
defined in the construction requirements in para-
drums on end. When drums are laid on their sides,
graph 6-1. General purpose electrical installations
they will shed water rapidly due to the geometry of
are adequate. Noncombustible and corrosion-
the drums, and there will be no areas for water to
resistant partitions sealed to the floor to prevent
collect and cause corrosion. Inspection of drums is
spread of leaking acid are recommended. The
made easier when they are laid on their sides since
building should have safety equipment such as eye
the tops are always visible.