rays involved in the production of radiation injuries are
the alpha and beta particles, the neutron, and the
gamma ray. These particles and rays produce their
effect by ionizing the chemical compounds that make
up the living cell. If enough of these particles or rays
disrupt a sufficient number of molecules within the
cell, the cell will not be able to carry on its normal
functions and will die.
ALPHA.Alpha particles are emitted from the
nucleus of some radioactive elements. Alpha particles
produce a high degree of ionization when passing
through air or tissue. Also, due to their large size and
electrical charge, they are rapidly stopped or absorbed
by a few inches of air, a sheet of paper, or the
superficial layers of skin. Therefore, alpha particles do
not constitute a major external radiation hazard.
However, because of their great ionization power, they
constitute a serious hazard when taken into the body
through ingestion, inhalation, or an open wound.
BETA.Beta particles are electrons of nuclear
origin. The penetration ability of a beta particle is
greater than an alpha particle, but it will only penetrate
a few millimeters of tissue and will most probably be
shielded out by clothing. Therefore, beta particles, like
alpha particles, do not constitute a serious external
hazard; however, like alpha particles, they do
constitute a serious internal hazard.
NEUTRONS.Neutrons are emitted from the
nucleus of the atom.
Their travel is therefore
unaffected by the electromagnetic fields of other
atoms. The neutron is a penetrating radiation which
interacts in billiard-ball fashion with the nucleus of
small atoms like hydrogen. This interaction produces
high-energy, heavy-ionizing particles that can cause
significant biological damage similar to that produced
by alpha particles.
GAMMA RAYS.Gamma rays are electro-
magnetic
waves.
Biologically, gamma rays are
identical to x-rays of the same energy and frequency.
Because they possess no mass or electrical charge, they
are the most penetrating form of radiation. Gamma
rays produce their effects mainly by knocking orbital
electrons out of their paththereby ionizing the atom
so affectedand imparting to the ejected electron.
Neutrons and gamma rays are emitted at the time of the
nuclear explosion, along with light. Gamma rays and
beta particles are present in nuclear fallout along with
alpha particles from unfissioned nuclear material.
Neutrons and gamma rays are an important medical
consideration in a nuclear explosion since their range
is great enough to produce biologic damage, either
alone or in conjunction with blast and thermal injuries.
PROTECTION AND TREATMENT
Preparations for the protection and treatment of
projected casualties of a nuclear attack must be made
in advance of any such assault.
Action before Nuclear Explosion
If there is sufficient warning in advance of an
attack, head as quickly as possible for the best shelter
available. This is the same procedure as would be used
during an attack by ordinary, high-explosive bombs.
At the sound of the alarm, get your protective mask
ready.
Proceed to your station or to a shelter, as
ordered. If you are ordered to a shelter, remain there
until the all clear signal is given.
In the absence of specially constructed shelters
during a nuclear explosion ashore, you can get some
protection in a foxhole, a dugout, or on the lowest floor
or basement of a reinforced concrete or steel-framed
building. Generally, the safest place is in the basement
near walls. The next best place is on the lowest floor in
an interior room, passageway, or hall, away from the
windows and, if possible, near a supporting column.
Avoid wooden buildings when possible. If you have no
choice, take shelter under a table or bed rather than
going out into the open. If you have time, draw the
shades and blinds to keep out most of the heat from the
blast. Only those people in the direct line of sight of
thermal emission will be burn casualties; that is,
anything that casts a shadow will afford protection.
Tunnels, storm drains, and subways can also provide
effective shelter.
In the event of a surprise attack, no matter where
you areout in the open on the deck of a ship, in a ship
compartment, out in the open ashore, or inside a
buildingdrop to a prone position in a doorway or
against a bulkhead or wall. If you have a protective
mask with you, put it on. Otherwise, hold or tie a
handkerchief over your mouth and nose.
Cover
yourself with anything at hand, being especially sure to
cover the exposed portions of the skin, such as the face,
neck, and hands. If this can be done within a second of
seeing the bright light of a nuclear explosion, some of
the heat radiation may be avoided. Ducking under a
table, desk, or bench indoors, or into a trench, ditch, or
vehicle outdoors, with the face away from the light,
will provide added protection.
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