(5) Flammable and combustible materials must
of a spill. Unprotected porous surfaces such as
be kept segregated from other storage items to
prevent large-scale damage.
in the removal of such a wall, plaster dust may
(6) AH hazardous materials storage areas
should be identified as dangerous areas and warn-
partitions, preferably with vitreous enamel surfaces,
ings about smoking and other flammable items
are probably the most easy to handle of the
should be posted.
materials. A concrete block wall with a special
smooth hard surface coating will generally reduce
6-2. Radioactive storage areas.
porosity to a satisfactory degree. Partition walls
should be constructed so as to shield the stored
a. General. The storage of radioactive material
radioactive material from personnel who must enter
involves serious health-related hazards that are not
the building, and there should be baffle wall
readily apparent. Radioactive material gives off
construction or positive interlocks at these en-
radioisotopes which emit several types of radiation
trances to prevent escape of radiation.
that are damaging to human tissue. The hazard is
(3) Ceilings. Ceilings serve as the support for
complicated by the fact that the radiation is not
service pipes, heating and ventilating ducts, and
detectable by any of the human senses.
light fixtures in addition to their normal functions.
b. Location and containment requirements.
Structural framing, duct work, and piping runs
Buildings that are used to store radioactive material
should be planned to obviate the need for sus-
do not have to be separate facilities, although for
pended ceilings. Where suspended ceilings are
purposes of safety in case of a fire, it is
justifiable for providing certain conditions of clean-
recommended that a separate building be con-
liness, lighting, and ventilation, gypsum board with
structed for the housing of all stored radioactive
taped joints or removable metal panels may be
material. If the depot's radioactive storage mission
used. If the ceiling is merely the exposed lower side
is small and construction of an entire building is not
of the floor above, it should be given a smooth,
justified, a portion of an existing building can be
nonporous finish. Pipes, ducts, and conduits leading
modified to provide the containment requirements
out of the containment area should be baffled to
necessary for safe storage.
prevent the escape of radiation.
c. Construction requirements. Buildings in
(4) Protective coatings.
which radioactive materials are to be stored should
(a) Through the proper selection of materials
preferably be single story without basements or
the designer can economically facilitate decon-
other below-grade spaces. Construction should be
tamination efforts. Materials which are expensive
fire resistive or noncombustible, including interior
but easily cleaned, or materials which are inexpen-
finish, acoustical or insulating treatments, and parti-
sive and easily replaced may be used. Metal with a
vitreous enamel coating is a good example of the
(1) Floors. Care should be taken to determine
first group; strippable paint is typical of the second.
the load to be carried by the floor since the
Ordinary paint is usually too porous to prevent
shielding material used to contain the radioactive
materials can often be quite heavy. If the stored
found that most of the organic paints tested under
material is flammable in addition to being radioac-
intense radiation tend to blister and check.
tive, the floor should be electrically conductive or
(b) Low-porosity surface coatings for
nonsparking and should have a continuous surface
application to various wall constructions can be
to facilitate ease of cleaning and decontamination in
obtained through the use of certain commercially
case of spills of radioactive liquids and powdered
prepared coatings including high gloss enamel and
solids. A concrete base covered with waterproof
plastic paints. These materials have been found to
paper or metal foil and a top surface of impervious
provide satisfactory surfaces where spills are
flooring materials in sheet or tile form is adequate.
The floor should be waxed to fill the cracks in
(c) Removable sheeting or strippable coatings
divisions and to provide the required surface
can be used to cover surfaces directly exposed to
contamination. These coatings are plastic solutions
(2) Walls and partitions. Exterior walls of the
usually containing flammable solvents which can be
building should be of a nonporous material and
applied with spray guns to specially prepared bases
partitions within the building which separate high
and removed without great difficulty. The use of
radiation areas from low radiation areas or secure
spray guns for applying such materials may be
areas should also be nonporous. These surfaces
hazardous, especially in small areas or rooms. Care
should also be smooth for ease of cleaning in case
should be taken to provide plenty of forced