Ludlum Measurements 2241-2, Руководство пользователя

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Model 2241-2RK Technical Manual
Section 6
Ludlum Measurements, Inc. Page 6-1 July 2012
Radiation Basics
Radiation and Life
Adapted from Eric J. Hall’s book, “Radiation and Life”
Radiation is energy traveling through space. Sunshine is one of the most
familiar forms of radiation. It delivers light, heat, and suntans. We control its
effect on us with sunglasses, shade, air conditioners, hats, clothes, and
sunscreen.
There would be no life on earth without lots of sunlight, but we have
increasingly recognized that too much of it on our bodies is not a good
thing. In fact, it may be dangerous, so we control our exposure to it.
Sunshine consists of radiation in a range of wavelengths from long-wave
infrared to short-wavelength ultraviolet, which creates the hazard.
Beyond ultraviolet are higher energy kinds of radiation that are used in
medicine and which we all get in low doses from space, from the air, and
from the earth. Collectively we can refer to these kinds of radiation as
ionizing radiation . It can cause damage to matter, particularly living tissue.
At high levels it is therefore dangerous, so it is necessary to control our
exposure.
Background radiation is that which is naturally and inevitably present in our
environment. Levels of this can vary greatly. People living in granite areas or
on mineralized sands receive more terrestrial radiation than others, while
people living or working at high altitudes receive more cosmic radiation. A
lot of our natural exposure is due to radon, a gas which seeps from the
earth's crust and is present in the air we breathe.
Section
6