roentgen.
(R; r) A special unit of exposure to gamma (or X~-) radiation.
[It is defined prefisely as the
coulomb in i kijiogram of dry air under standard conditions.
An exposure of 1 rffentgen results
Quantity of gamma (or X-) rays that will produce electrons (in jon pairs) with a total—icharge of 2.58
x 10-*
in the ceposition of about 94 ergs of energy in 1 gram of soft body tissue.
Hence, anfjexposure of
l roentgen is approximately equivalent to an absorbed dose of 1 rad in soft tissue.
RSSU.
Radiological Safety Support Unit fArmy).
RTTY¥.
Radio teletype.
SA-16. Air Force general purpose amphibian for air-sea rescue work. Manufactured by Grumm
Engineering Corporation, New York. Redesignated UY-16. Used in CASTLE for search and
SAC.
Aircraft
escue.
Strategic Air Command (Air Force).
sampler aircraft. Aircraft used for collection of gaseous and particulate samples from nuc
determine the level of radioactivity or the presence of radioactive substances.
SC.
ar clouds to
Sandia Corporation, Albuquerque, New Mexico.
scattering.
The diversion of radiation (thermal, electromagnetic and nuclear) from its orig§nal path as a
result of interactions {or collisions) with atoms, molecules, or larger particles in th
atmosphere
or other media Setween the source of the radiations (e.g., a nuclear explosion) and a pBint some
distance away. As a result of scattering, radiations (especially gamma rays and neutrofs) will be
received at such a point from many directions instead of only from the direction of thellsource.
See
also skyshine.
SCEL.
Signal Corps Engineering Laboratories, Ft. Monmouth, New Jersey (Army).
scintillation.
A flash of light produced by ionizing radiation in a fluor or a phosphor, whfich may be
crystal, plastic, gas, or liquid.
shear (wind).
Refers to differences in direction (directional shear) of wind at different afititudes.
shielding. Any material or obstruction that absorbs (or attenuates) radiation and thus tend
personnel or equipment from the effects of a nuclear explosion. A moderately thick lay
opaque material will provide satisfactory shielding from thermal radiation, but a consi
ness of material of high density may be needed for gamma radiation shielding.
See alsa
to protect
of any
rable thickttenuation.
shock. Term used to describe a ‘destructive force moving in air, water, or Earth caused by ddtonation of a
nuclear detonation.
shock wave. A continuousty propagated pressure pulse (or wave) in the surrounding medium, which may be
air, water, or Earth, initiated by the expansion of the hot gases produced in an explos
sievert (Sv).
A recently introduced ICRP measure of "dose equivalent" that takes into accoung the "quality
factor" of different sources of ionizing radiation.
SIO.
One sievert equals 100 rem.
Scripps Institution of Oceanography, La Jolla, California.
skyshine,
Radiation, particularly gamma rays from a nuclear detonation, reaching a target friim many direc-
tions as a result of scattering by the oxygen and nitrogen in the intervening atmosphere
slant range. The straight-line distance of an aircraft at any altitude from ground zero or te distance
from an airburst to a location on the ground.
SRI.
Stanford Research Institute, Stanford, California.
stratosphere.
Upper portion of the atmosphere, approximately 7 to 40 miles (11 to 64 km) abofle the
Farth's surface, in which temperature changes but little with altitude and cloud formatigns are rare.
surface burst.
surface zero.
point.
survey meters.
A nuclear explosion on the land surface, an island surface or reef, or on a bdrge.
See ground zero.
Also the location on the ground surface directly above an underground zero
Portable radiation detection instruments especially adapted for surveying or
fnspecting an
area to establish the existence and amount of radiation present, usually from the standpdint of radio-
logical protection.
Survey instruments are customarily powered by self-contained batter#es and are
designed to respond quickly and to indicate directly the exposure rate conditions at the point of interest. See AN/PDR-36, Geiger-Mueller counter, and jion-chamber-type survey meter.
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