DOSIMETER
An instrument for measuring and recording the total
accumulated dose of (or exposure to) ionizing
radiation. Instruments worn or carried by individuals
are called personnel dosimeters.
DOSIMETRY
The theories about and applications of the techniques
involved in measuring and recording radiation doses and
dose rates.
Its practical application includes the use
of various types of radiation detection instruments to
measure radiation.
EXPOSURE, X or
A measure of the ionization produced by gamma (or X)
rays in air. The exposure rate, exposure per unit of
time, is commonly used to indicate the gamma radiation
intensity of a source. The unit of exposure is the
roentgen (R).
FALLOUT
The descent to the earth’s surface of particles contaminated with radioactive material as a result of a
GAMMA RADIATION
nuclear detonation.
The term also applies to the
contaminated particulate matter itself.
FILE A
The NTPR data base consisting of information extracted
FILM BADGE
A personnel dosimeter utilizing photographic film to
FIREBALL
The luminous sphere of hot gases that forms a few
thousandths of a second after a nuclear detonation.
FISSION
The splitting of a heavy nucleus into two or more
radioactive nuclei, accompanied by the release of a
from telephone calls to the DNA toll-free lines and,
from letters drafted by participants in the atmospheric
nuclear weapons tests and in the postwar occupation of
Hiroshima and Nagasaki.
measure the radiation dose received by the wearer. The
badge is usually clipped to an outer garment above
waist level. The dose is calculated from the degree of
film darkening that results from exposure to radiation.
large amount of energy and generally one or more
neutrons and one or more gammas.
FUSION
The formation of a heavier nucleus from two lighter
nuclei, accompanied by the release of a large amount of
energy.
GAMMA RAYS
A form of electromagnetic radiation emitted spontane-
ously from the nuclei of certain radioactive elements,
often in conjunction with the emisson of alpha or beta
particles. Gamma rays also result from other nuclear
reactions, such as fission and neutron capture. Gamma
rays are identical to X-rays, except that they
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