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The energy of ionizing radiation is measured in electronvolts (eV). One
electronvolt is an extremely small amount of energy. Commonly used multiple
units are kiloelectron (keV) and megaelectronvolt (MeV).
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6.24150913 × 10 MeV = 1 joule
1 joule per second = 1 watt
1 keV = 1000 eV, 1 MeV = 1000 keV
Watt is a unit of power, which is the equivalent of energy (or work) per unit
time (e.g., minute, hour).
Under normal conditions, everyone is exposed to background ionizing
radiation from two major sources: continuous, naturally occurring radiation from
space and radiation from radioactive elements and technology-enhanced (often
referred to as "man-made") radiation sources. Natural sources of radiation
constitute the major source of radiation exposure to the populations of most, if not
all, countries, with the next largest source being applications of medical
technology.
In the Ukraine the average annual effective dose of naturally occurring
background radiation is about 2.4 mSv (0.24 rem) per year. A major portion of this
arises through internal exposures, namely, 1.3 mSv (0.13 rem) from airborne radon
and its decay products, and 0.4 mSv (0.04 rem) from naturally occurring
radionuclides in the human body. The remainder comes from external sources,
namely, 0.37 mSv (0.037 rem) from cosmic radiation and an equal amount from
naturally occurring radioactive materials in the ground (terrestrial). The effective
dose from all natural sources during a 70-year lifetime is approximately 170 mSv
(17 rem). Levels of background radiation vary significantly across geographic
areas.
In addition to the doses from background radiation, some soldiers are

engaged in duties in which they are at risk of exposure to higher levels of ionizing
radiation. Examples of such duties include repairing and maintaining radioactive
commodities (e.g., ammunition containing depleted uranium and luminescent
sights containing tritium), flying at high altitudes, and administering radiation for
medical diagnosis and therapy.
The energy of ionizing radiation is measured and described in a number of
ways. One can use a survey meter or other device to measure exposure-ionization
-1
in air caused by radiation. Exposure is measured in coulombs per kilogram (C kg )
*
of air, formerly the roentgen (R). This measurement of exposure applies only to
ionizing electromagnetic radiation, such as gamma and x rays, not to particulate
radiation (e.g., alpha or beta particles). In the field (outside the laboratory),
exposure is the quantity that is measured, although for convenience, it is
commonly assumed that exposure and absorbed dose (see below) are the same
when expressed in traditional units (i.e., 1 R = 1 rad).
Although beta and alpha radiations can be detected in the field,
determination of their contribution to tissue dose is a complex process not
reasonably implemented except under laboratory conditions. Exposure to alpha-
and beta-emitting radionuclides, expressed in terms of their intake, is related to

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