Basics Of Radiation And Its Measurement; Ionizing Radiation - Radiation Alert Inspector + Manuel D'instructions

manufacturer at the following address:
S.E. International, Inc.
P.O. Box 39, 436 Farm Rd.
Summertown, TN USA 38483-0039
Tel 931-964-3561, Fax 931-964-3564
E-mail: radiationinfo@seintl.com

6 Basics of Radiation and Its Measurement

This chapter briefly tells what radiation is and how it is measured. This
information is provided for users who are not already familiar with the subject. It
is helpful in understanding how the Inspector+ works and in interpreting your
readings.

Ionizing Radiation

Ionizing radiation is radiation that changes the structure of individual atoms by
ionizing them. The ions produced in turn ionize more atoms. Substances that
produce ionizing radiation are called radioactive.
Radioactivity is a natural phenomenon. Nuclear reactions take place continuously
on the sun and all other stars. The emitted radiation travels through space, and a
small fraction reaches the Earth. Natural sources of ionizing radiation also exist in
people and in the ground. The most common of these are uranium and its decay
products.
Ionizing radiation is categorized into four types:
X-rays are manmade radiation produced by bombarding a metallic target with
electrons at a high speed in a vacuum. X-rays are electromagnetic radiation of
the same nature as light waves and radio waves, but at extremely short
wavelength, less than 0.1 billionth of a centimeter. They are also called photons.
The energy of X-rays are millions of times greater than that of light and radio
waves. Because of this high energy level, X-rays penetrate a variety of materials,
including body tissue.
Gamma rays are almost identical to X-rays. Gamma rays generally have a
shorter wavelength than X-rays. Gamma rays are very penetrating; thick lead
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