entered the market as radioactive rings and other types of gold jewelry. Some imported cloisonne being glazed with
uranium oxide exceeds U.S. limits.
Some gems are irradiated by an electron beam or in an accelerator to enhance their color. Irradiated gems typically are
held until there is no residual activity remaining.
ROCK COLLECTIONS: Many natural formations contain radioactive materials. Hobbyists who collect such things should
vent the rooms in which these items are stored and be careful to avoid inhaling the fine dust particles from these
samples.
POTTERY: Some types of pottery is glazed with uranium oxide. To the best of our knowledge, this process has been
discontinued, although some of these pieces are still in circulation.
GLOSSARY
ALPHA: Positively charged particles emitted from the nucleus of an atom. Alpha particles are relatively large, and very
heavy. Due to this strong (+) charge and large mass, an alpha particle cannot penetrate far into any material. A sheet of
paper or an inch of air can usually stop most alpha particles.
BACKGROUND RADIATION: Naturally occurring radiation is always present, it includes high energy gamma rays from
the sun and outer space and alpha, beta, and gamma radiation emitted from elements in the earth.
BETA PARTICLES: Negatively charged particles emitted from an atom. Beta particles have a mass and charge equal to
that of an electron. They are very light particles (about 2,000 times less mass than a proton) and have a charge of -1.
Because of their light mass and single charge, beta particles can penetrate more deeply than alpha particles. A few
millimeters of aluminum will stop most beta particles.
Bq (Becquerels): A quantity of radioactivity in which one atom is transformed per second. 1 dps (one disintegration per
second).
CPM (counts per minute): The unit of measurement usually used to measure alpha and beta radiation.
GAMMA RAYS: Short wavelength electromagnetic radiation higher in frequency and energy than visible and ultraviolet
light. Gamma rays are emitted from the nucleus of an atom. These high energy photons are much more penetrating than
alpha and beta particles.
ION: An atomic particle, atom, or molecule that has acquired an electrical charge, either positive or negative, by gaining
or losing electrons.
IONIZATION: The process by which neutral atoms of molecules are divided into pairs of oppositely charged particles
known as ions.
IONIZING RADIATION: Radiation capable of producing ionization by breaking up atoms or molecules into charged
particles called ions.
RADIATION: The emission and propagation of energy through space or through matter in the form of particles or waves.
ROENTGEN (rent-gen): A basic unit of measurement of the ionization produced in air by gamma or x-rays. One
Roentgen (R) is exposure to gamma or x-rays that will produce one electrostatic unit of charge in one cubic centimeter
of dry air. One thousand milliroentgen (1,000 mR)= 1R.
RADIOISOTOPE: A natural occurring or artificially produced radioactive form of an element.
SIEVERT: A unit of dose equivalent. 1 Sv= 100 roentgens, 10 μSv/hr = 1 milliroentgen/hr. (μSv micro-Sievert, micro is
one millionth, milli is one thousandth.)
X-RAYS: Electromagnetic radiation (photons) of higher frequency and energy than visible and ultraviolet light, usually
produced by bombarding a metallic target with high speed electrons in a vacuum. X-rays are photons emitted by
interactions involving orbital electrons rather than atomic nuclei. X-rays and gamma rays have the same basic
characteristics. The only difference between them is their source of origin.
5
To Next Page
Loading...
Need help?
General
